Patent Application
20250129577
The present invention relates to a contact determination apparatus, a contact determination system, a contact determination method, and a program.
In the construction industry, shortage of labor force and succession of skills due to, for example, aging of field workers and decrease of young workers have become problems requiring urgent attention. Therefore, as an aid to the skill of an operator, there is a technique to, by remote control, execute the work of discharging the earth and sand excavated by a work machine. For example, Patent Literature 1 discloses a control apparatus for causing excavated earth and sand generated in a construction site or the like to be discharged into a designated place. The control apparatus disclosed in Patent Literature 1 carries out control for prohibiting the output of an earth and sand discharge operation signal, in a case where the direction in which the turning body operated by a loading instruction signal faces is a direction in which a predetermined area resides.
The control apparatus disclosed in Patent Literature 1 causes earth and sand to be discharged at a position where a load-carrying vehicle (such as a dump truck) exists so that the earth and sand can be loaded on the load-carrying vehicle without spilling the earth and sand.
On the other hand, in a case where a load-carrying vehicle on which earth and sand or the like is loaded travels on a public road, it is necessary to shape the shape (loading style) of the loaded earth and sand or the like. For example, it is necessary to level and load the earth and sand to prevent the earth and sand from spilling during traveling. Unfortunately, in the technique disclosed in Patent Literature 1, it is possible to load the discharged earth and sand on the load-carrying vehicle without spilling the discharged earth and sand, but the shape of the discharged earth and sand is not considered.
Therefore, even when earth and sand are loaded on the load-carrying vehicle by using the technique disclosed in Patent Literature 1, there may be cases where measures for preventing earth and sand from spilling during traveling are not sufficient in a state in which earth and sand are not shaped. In addition, in a case where the operator cannot determine the loading style visually during driving such as automatic driving, or in a case where an operator who is lacking in skill fails to determine the loading style, it is not possible to carry out an operation such as an operation for adjusting the position of the discharged earth and sand.
An example aspect of the present invention has been made in view of the above problem, and an example object of the present invention is to provide a technique capable of shaping a placed target object into a desired shape with use of a work machine.
A contact determination apparatus in accordance with an example aspect of the present invention includes: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
A contact determination method in accordance with an example aspect of the present invention includes: acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
A contact determination system in accordance with an example aspect of the present invention includes: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
A contact determination program in accordance with an example aspect of the present invention is a program for causing a computer to function as a contact determination apparatus, the program causing the computer to function as: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
According to an example aspect of the present invention, it is possible to shape a placed target object into a desired shape with use of a work machine.
A first example embodiment of the present invention will be described in detail with reference to the drawings. The present example embodiment is a basic form of an example embodiment described later.
As illustrated in
The acquisition unit 11 acquires information pertaining to a position of at least one movable part among one or more movable parts provided in the backhoe 40. The position may be a rotational position or a translational position. The rotational position is, for example, a rotation angle of the movable part in a case where the movable part is a member that is rotated. The translational position is, for example, an amount of translation of the movable part in a case where the movable part is a member that is translated. As an example, these pieces of information are detected by sensors, which will be described later, and are transmitted to the acquisition unit 11.
The position in accordance with the present example embodiment may be a relative position relative to a reference point in the backhoe 40 or an absolute position in a space that includes the backhoe 40 and the target object. The information pertaining to the position is information from which the relative position or the absolute position of the movable part of the backhoe 40 can be derived. The information pertaining to the position is information from which the position of the movable part (hereinafter the position of the movable part may also be described as a posture of the movable part) can be derived. The movable part of the backhoe 40 will be described later.
The determination unit 12 carries out determination of contact between the work machine and the target object on the basis of a result of a comparison between an amount of change in the position of a movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the backhoe 40 and earth and sand, which are the target object. The amount of change in the position is the amount of change in the relative position or the absolute position of the movable part. Specifically, the amount of change in the position may be an amount corresponding to the first-order derivative of position data (e.g., a movement speed amount of the movable part) or an amount corresponding to the second-order derivative of the position data (e.g., a movement acceleration amount of the movable part). In addition, the above-described threshold value is a threshold value used for determination as to whether contact between the work machine and the target object has occurred, and can be set in accordance with various conditions such as the type of the work machine, the content of work, and the type and property of the target object. Thus, it is possible to use a threshold value that is determined in advance for each of the conditions on the basis of, for example, an experiment or an estimation. “In advance” only needs to be before the contact determination is carried out, and may be, as an example, any timing such as the time of initial setting for autonomous drive (for example, the time of calibration when the work machine is carried into a work site), the time of input during an inspection before the start of work, a maintenance, and an inspection. Note that the contact determination system 1 may include a calculation unit (not illustrated) that calculates the amount of change in the position.
The contact in the contact determination is not limited to a planar contact and also includes insertion of a rod-shaped member into the target object and insertion of a planar member into the target object. Specifically, the contact also includes insertion of a fork-shaped or blade-shaped member provided at an end portion of an arm of a work machine for leveling or reclamation into a target object such as earth and sand.
The controller 44 is mounted in the backhoe 40 and carries out action control of the backhoe 40 on the basis of a received action control signal. “Mounted” is referred to as being built into the backhoe 40 or being retrofitted to a common and commercially available backhoe (such as, for example, carrying a small computer in an occupant seat). For example, in the case of the backhoe 40 designed with autonomous driving in mind, the controller 44 is built into the backhoe 40 at the time of being marketed. However, in the case of a backhoe which is assumed to be operated by an occupant, a small computer into which a control program is incorporated may be retrofitted as the controller 44 to the backhoe. In the case of retrofitting to an occupant-operated backhoe, a configuration may be employed in which an attachment is mounted on a lever, and the lever is operated by instructions given to the attachment so that the backhoe is operated. Note that a configuration may be employed in which the controller 44 is installed in an area around the backhoe (in a range in which communications are possible via a communication network) and transmits a control signal therefrom to the backhoe 40. The action control signal, which is a signal for controlling the action of each part of the backhoe 40, is generated by an action control apparatus, which will be described later, and is transmitted to the controller 44.
The configuration of the backhoe 40 to which the contact determination system 1 is applied will be described with reference to the drawing. 201 of
As illustrated in 201 of
The traveling part 49 is a traveling part that allows the backhoe 40 to move forward and backward, and to turn right and left. The traveling part 49 travels with use of, for example, an endless track belt. The movable part includes the main body 45, a boom 41 (first movable part) that is connected to the main body 45, an arm 42 (second movable part) that is connected to an end portion of the boom 41, and a bucket 43 (third movable part) that is connected to an end portion of the arm 42. The acquisition unit 11 acquires information pertaining to a rotational position of at least one movable part among these movable parts.
The main body 45 can turn on the traveling part 49 in a plane substantially parallel to the ground. “Substantially parallel” is not limited to perfectly parallel, and a plane with unevenness or inclination falling within a certain error range is also regarded as being virtually parallel. Note that, in a case where the backhoe 40 is on a horizontal ground, the plane parallel to the ground is a horizontal plane. Therefore, hereinafter, the plane substantially parallel to the ground is referred to as a “horizontal plane” for convenience.
The boom 41 can turn and return around a boom shaft 46 in a plane that is substantially perpendicular to the horizontal plane. “Substantially perpendicular” is not limited to perfectly perpendicular, and a plane with an inclination falling within a certain error range is also regarded as being virtually perpendicular. The arm 42 can turn and return around an arm shaft 47 on the same turning plane as that of the boom 41. The bucket 43 can turn and return around a bucket shaft 48 on the same turning plane as that of the arm 42. Causing each of individual movable parts to turn changes the posture of the backhoe 40. Note that the individual movable parts are referred to as the main body 45, the boom 41, the arm 42, and the bucket 43.
For each movable part, a spatial position of the movable part can be derived from a turning angle of the movable part. For example, a position of the arm shaft 47 relative to a predetermined position of the traveling part 49 can be derived from the turning angle of the main body 45 and the turning angle of the boom 41. Then, the position of the bucket shaft 48 can be derived from the position of the arm shaft 47 and the turning angle of the arm 42. Then, the position of the bottom surface of the bucket 43 can be derived from the position of the bucket shaft 48 and the turning angle of the bucket 43.
Each of the sensors detects information pertaining to the position of the movable part of the backhoe 40. Examples of the information pertaining to the position of the movable part include, but not limited to, a turning angle of each individual movable part, and the like. In the present example embodiment, each of the sensors is a sensor that detects a turning angle of the body 45, the boom 41, the arm 42, or the bucket 43. The turning angle detected by each of the sensors (information pertaining to the position) is transmitted to the acquisition unit 11.
Specifically, the sensor that detects the turning angle of the main body 45 is, for example, a gyro sensor. Alternatively, this sensor may be an encoder that detects the number of rotations of a motor that causes the main body 45 to turn. The sensor that detects the turning angle of the boom 41 is an inclination sensor or a gyro sensor that detects an angle of the boom 41 from the horizontal plane. Alternatively, this sensor may be an encoder that detects a movement distance of a rod of a hydraulic cylinder which causes the boom 41 to turn. Similarly, the sensor that detects the turning angle of the arm 42 is, for example, an inclination sensor, a gyro sensor, or an encoder that detects an angle of the arm 42 with respect to the boom 41. The sensor that detects the turning angle of the bucket 43 is, for example, an inclination sensor, a gyro sensor, or an encoder that detects an angle of the bucket 43 with respect to the arm 42.
The controller 44 has a processor, a memory, and a communication interface (none of which are illustrated). By loading and executing a program stored in the memory, the controller 44 acquires a detection value of the sensor and transmits the acquired detection value to the action control apparatus (not illustrated) via a communication interface. Further, by loading and executing the program stored in the memory, the controller 44 controls each part of the backhoe 40 in accordance with an action control signal received from the action control apparatus (not illustrated) via the communication interface.
For example, the controller 44 causes some or all of the main body 45, the boom 41, the arm 42, and the bucket 43 to turn in accordance with the action control signal. For example, in a case where some or all of the main body 45, the boom 41, and the arm 42 are turned, the position of the bucket 43 is changed, and the bucket 43 is moved. In addition, for example, in a case where the bucket 43 is turned, the bucket 43 carries out an action of shoveling earth and sand, which are a target object TO, or an action of releasing the earth and sand.
In the present example embodiment, an applicable work machine is not limited to the backhoe 40 and can be, for example, a bulldozer. A configuration of a bulldozer 40a to which the contact determination system 1 is applied will be described with reference to the drawing. 202 of
As illustrated in 202 of
The following will describe differences from the above-described backhoe 40.
Movable parts of the bulldozer 40a include a main body 45a, a cylinder 41a (first movable part) and a rod 42a (second movable part) that are attached to the main body 45a, and a blade 43a (third movable part) attached to an end portion of the rod 42a.
The bulldozer 40a translates the rod 42a back and forth to move the blade 43a back and forth. This allows the bulldozer 40a to carry out, for example, leveling by pushing through earth and sand, which is a target object TO. Further, causing the cylinder 41a to turn up and down with use of a hydraulic cylinder (not illustrated) allows the blade 43a to be moved up and down. Alternatively, the blade 43a itself may be turned up and down with use of a hydraulic cylinder (not illustrated). The movable parts of the bulldozer 40a refer to the cylinder 41a, the rod 42a, and the blade 43a.
Various sensors detect the state of the bulldozer 40a. Examples of the state of the bulldozer 40a include, but not limited to, a turning angle or a translation amount of each individual movable part. In the present example embodiment, the sensors are a sensor that detects the turning angle of the main body 45a, a sensor that detects the turning angle of the cylinder 41a, a sensor that detects the translation amount of the rod 42a, and a sensor that detects the turning angle of the blade 43a. These sensors are similar to those used in the backhoe 40. That is, as the sensor that detects the turning angle, a gyro sensor, an encoder, or the like can be used. As the sensor that detects the translation amount, an encoder or the like that detects the amount of movement of the rod 42a can be used. The turning angle detected by the sensor or the amount of translation detected by the sensor is transmitted to the acquisition unit 11.
As described above, the work machine to which the contact determination system 1 is applied is not limited to the backhoe 40, and includes a work machine that carries out excavation, shaping, collection, transportation, or the like of a target object, such as a shovel car, a bulldozer, or a wheel loader. Further, a target object to be handled by the work machine in accordance with the present example embodiment is not limited to earth and sand, and includes: a granular body such as grain and sand gravel; powder such as cement; and an amorphous object such as rubble. In addition, the target object is not limited to an amorphous object, and may be a structure that is targeted for determination as to whether contact of the structure with the movable part has occurred and an immovable object such as the ground.
Next, a specific example of the amount of change in the position will be described with reference to the drawing. For example, consider a case in which an action of leveling earth and sand loaded on a load-carrying vehicle is carried out with use of the bucket 43 of the backhoe 40. The earth and sand that have only been released on the load-carrying vehicle is in a state of being high at and near the center and being lowered toward the outer edge of the earth and sand or in a state in which large bumps and dips remain in the earth and sand. Thus, an action control unit (not illustrated) executes the work of pressing a bottom surface portion of the bucket 43 against a heap of the earth and sand and leveling the earth and sand so as to reduce the difference in height of the earth and sand.
Specifically, the action control unit transmits, to the controller 44, a lowering control signal for lowering the bucket 43 which has been positioned in advance above a raised portion of the earth and sand at a constant speed. Upon receiving the lowering control signal, the controller 44 carries out control for lowering the bucket 43. Note that the control for lowering the bucket 43 can be carried out by control for changing the rotational position of the arm 42 or the boom 41.
Assume that the controlled lowering speed from the time t1 to the time t2 is v1, and a lowering speed from the time t2 to the time t3 is v2. The lowering speeds v1 and v2 are examples of the amount of change in the position mentioned above. The contact determination system 1 includes a calculation unit (not illustrated) that calculates the lowering speeds v1 and v2, which are each the amount of change in the position, from the information (height information) pertaining to the position. Note that, since the lowering speed is a speed in a direction in which the position is lowered, both v1 and v2 are positive values.
Here, in a case where v2 is equal to or less than a threshold value T1, the determination unit 12 may determine that contact between the bucket 43 and the earth and sand has occurred. Note, however, that the threshold value T1 is set to a value less than the controlled lowering speed v1.
In addition, in a case where the lowering speed v2, which is the amount of change in the position, is equal to or less than the threshold value T1 in a time period T that serves as a criterion on which to determine contact between the bucket 43 and the earth and sand, the determination unit 12 may determine that contact between the bucket 43 and the earth and sand has occurred. In the example shown in
The threshold value T1 is set to a value less than the controlled lowering speed v1. The degree of a numerical value of the lowering speed v1 can be ascertained in advance in accordance with, for example, the action control signal generated by the action control apparatus and the specification of the hydraulic cylinder in the backhoe 40.
As described above, employed in the contact determination system 1 in accordance with the present example embodiment is a configuration in which the contact determination system 1 includes: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on the basis of a result of a comparison between an amount of change in the position of the movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. Therefore, according to the contact determination system 1 in accordance with the present example embodiment, the amount of change in the position is calculated from the information pertaining to the position of the movable part, and the determination of contact between the work machine and the target object is carried out on the basis of the result of the calculation. This makes it possible to reliably carry out the determination of the contact. Thus, an effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
Next, a contact determination method S1 in accordance with the present example embodiment will be described with reference to the drawing.
As illustrated in
In step S12, the determination unit 12 carries out determination of contact between the work machine and the target object on the basis of a result of a comparison between an amount of change in the position of a movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. For example, in a case where the lowering speed of the bucket 43, which is the amount of change in the position calculated from the information pertaining to the position of the bucket 43, is equal to or less than a threshold value indicating the amount of change that serves as a criterion on which to determine contact between the bucket 43 and the earth and sand, the determination unit 12 determines that contact between the bucket 43 and the earth and sand, which are the target object, has occurred. Specific examples of the amount of change in the position and the contact determination are the same as those presented in the description of the determination unit 12 of the contact determination system 1.
Note that, in a case where the amount of change in the position is equal to or less than the threshold value in a time period that serves as a criterion on which to determine contact between the work machine and the target object, the determination unit 12 may determine that contact between the bucket 43 and the earth and sand, which are the target object, has occurred.
As described above, employed in the contact determination method S1 in accordance with the present example embodiment is a configuration in which information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine is acquired, and determination of contact between the work machine and a target object is carried out on the basis of a result of a comparison between an amount of change in the position of the movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. Thus, according to the contact determination method S1 in accordance with the present example embodiment, the effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
Next, a contact determination apparatus 100 in accordance with the present example embodiment will be described with reference to the drawing.
As described above, the contact determination apparatus 100 includes: an acquisition unit 11 that acquires information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination unit 12 that carries out determination of contact between the work machine and a target object on the basis of a result of a comparison between an amount of change in the position of the movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. The configurations of the acquisition unit 11 and the determination unit 12 are the same as the configurations of the acquisition unit 11 and the determination unit 12 of the contact determination system 1, respectively, and the descriptions thereof will be omitted. Further, details of the position and the information pertaining to the position and specific examples of the amount of change in the position and the contact determination are the same as those presented in the descriptions of the acquisition unit 11 and the determination unit 12 of the contact determination system 1.
The contact determination apparatus 100 carries out, as an example, determination of contact between a bucket of a backhoe, which is a work machine, and sand and earth, which are a target object targeted for work. Specifically, the acquisition unit 11 acquires, for example, information (for example, a turning angle) pertaining to the position of the bucket detected by various sensors disposed in the backhoe. Then, the amount of change in the position of the bucket is determined from the information pertaining to the position of the bucket, and, on the basis of the result of a comparison between the amount of change in the position of the bucket and a threshold value, whether the bucket has come into contact with the target object is determined.
Note that the contact determination apparatus 100 may include a calculation unit (not illustrated) that calculates the amount of change in the position from the information pertaining to the position. In such a case, the determination unit 12 refers to the lowering speed of the bucket, which is the amount of change in the position of the bucket calculated by the calculation unit, and, in a case where the lowering speed of the bucket is equal to or less than the threshold value, determines that contact between the bucket and the earth and sand, which are the target object, has occurred.
Note that, in a case where the amount of change in the position is equal to or less than a predetermined threshold value in a time period that serves as a criterion on which to determine contact between the work machine and the target object, the determination unit 12 may determine that contact between the bucket and the earth and sand, which are the target object, has occurred.
As described above, employed in the contact determination apparatus 100 in accordance with the present example embodiment is a configuration in which the contact determination apparatus 100 includes: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on the basis of a result of a comparison between an amount of change in the position of the movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. Thus, according to the contact determination apparatus 100 in accordance with the present example embodiment, the effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
As mentioned above, in the present example embodiment, determination of contact with the target object is carried out on the basis of the amount of change in the position of at least one movable part among one or more movable parts provided in the backhoe 40. Here, it is also considered possible to employ a configuration in which the backhoe 40 is configured to be capable of acquiring an excavation reaction force or the amount of change in the excavation reaction force so that the contact determination is carried out on the basis of the excavation reaction force or the amount of change in the excavation reaction force. However, the accuracy in detecting the excavation reaction force is generally lower than the accuracy in detecting the position of the movable part. Therefore, as described in the present example embodiment, carrying out determination of contact with the target object on the basis of the amount of change in the position of the movable part realizes contact determination with higher accuracy.
Further, as mentioned above, in the present example embodiment, determination of contact with the target object is carried out on the basis of a result of a comparison between the amount of change in the position of at least one movable part among one or more movable parts provided in the backhoe 40 and a threshold value. Here, the threshold value is not a so-called target control amount for moving the movable part of the backhoe 40 along a target trajectory and is a value which is set in advance for contact determination. In other words, the threshold value can be set in advance in accordance with, for example, a target object targeted for contact determination.
A second example embodiment of the present invention will be described in detail with reference to the drawings. The same reference numerals are given to constituent elements which have functions identical with those described in the first example embodiment, and descriptions as to such constituent elements are omitted as appropriate.
The contact determination apparatus 100A and the action control apparatus 150 are connected to a controller 44 of a backhoe 40, which is a work machine, via a communication network 50 so that information communication can be carried out. The backhoe 40 includes the controller 44. The communication network 50 and the backhoe 40 have configurations similar to those of the communication network 50 and the backhoe 40 described in the first example embodiment. In the present example embodiment, actions of individual apparatuses will be described by taking, as an example, a case in which the backhoe 40 carries out work of leveling earth and sand loaded on a dump truck 60.
Note that, regarding individual units of the contact determination apparatus 100A and the action control apparatus 150, the individual units of each apparatus do not necessarily have to be disposed in a single apparatus and may be disposed separately in a plurality of apparatuses. The same applies to other example embodiments. For example, in
The contact determination apparatus 100A includes an acquisition unit 110, a determination unit 120A, and a storage unit 130. The acquisition unit 110 acquires a signal transmitted from a sensor which is mounted on the backhoe 40. The sensor detects at least one piece of information selected from the group consisting of a turning angle and an amount of translation, which are pieces of information pertaining to a position of a movable part of the backhoe 40, and transmits the at least one piece of information to the acquisition unit 110.
The determination unit 120A determines whether the movable part has come into contact with the target object. The determination unit 120A includes an amount-of-change calculation unit 121, an elapsed time calculation unit 122, and a contact determination unit 123. The amount-of-change calculation unit 121 calculates an amount of change in the position of the movable part of the backhoe 40. The amount-of-change calculation unit 121 may be the calculation unit, described in the first example embodiment, that calculates the amount of change in the position. The elapsed time calculation unit 122 calculates how much time has elapsed in a continuous manner as the amount of time during which the amount of change in the position of the movable part of the backhoe 40 satisfies a condition for a predetermined threshold value. The contact determination unit 123 determines whether the movable part has come into contact with the target object with reference to the calculated amount of change in the position and the amount of time during which the amount of change in the position has continued.
The storage unit 130 records movable part position information MPI and threshold value information THI. The movable part position information MPI is information pertaining to the position of the movable part of the backhoe 40. Since the information pertaining to the position of the movable part is sequentially transmitted from the sensor(s) to the acquisition unit 110, the acquisition unit 110 sequentially records the information as the movable part position information MPI. Note that, in the storage unit 130, the movable part position information MPI, the threshold value information THI, or the like may be stored in association with a reception time and/or an absolute time.
The threshold value information THI is information pertaining to at least one selected from the group consisting of a threshold value and a time period. In the present example embodiment, the threshold value information THI recorded in the storage unit 130 is vt, which is a threshold value of a bucket lowering speed in the work of leveling earth and sand with use of the bucket 43 of the backhoe 40, and/or T, which is a time period during which the bucket lowering speed continues. As an example, the threshold value information THI may be information set by an operator's hand or may be information acquired from other site or apparatus via a communication network.
The trajectory generation unit 152 of the action control apparatus 150 generates a target trajectory of at least one movable part among one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part. As an example, the action control apparatus 150 generates a target trajectory of the bucket 43 that extends deep into (inward of) earth and sand TO below a surface of the earth and sand TO when viewed from the bucket 43. The action control unit 153 of the action control apparatus 150 generates a control signal for moving the bucket 43 along the target trajectory and transmits the control signal to the controller 44. The action control apparatus 150 corresponds to the action control apparatus described in the first example embodiment.
Specifically, the action control apparatus 150 includes the target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153. The action control apparatus 150 is a form of the action control means recited in the claims.
The target object position acquisition unit 151 acquires a position of a target object. As an example, the target object position acquisition unit 151 acquires information indicating the position of the target object from a sensor disposed in the vicinity of a work place. The sensor is, for example, a three-dimensional light detection and ranging (LiDAR), a stereo camera, a three-dimensional sensor (3D sensor) such as a time-of-flight (TOF) camera, or a depth camera. The target object position acquisition unit 151 derives the position of the target object (an absolute position in a work space or a relative position to the backhoe 40) with use of distance information acquired from the three-dimensional LiDAR.
The trajectory generation unit 152 generates a target trajectory (hereinafter also referred to simply as a “trajectory”) for moving the movable part (for example, the bucket 43) of the backhoe 40 from the acquired position of the target object and the work content. The trajectory may be a linear trajectory or may be a trajectory that includes a curve. It is also possible to linearly move the bucket 43 by adjusting the turning angles of the boom 41 and the arm 42. Note that, in a case where the acquired position of the target object is an absolute position, an absolute position of the backhoe 40 as well needs to be acquired. For example, by using a three-dimensional LiDAR or the like, both the absolute position of the target object in the work area and the absolute position of the backhoe 40 in the work area can be acquired together. The work content specifies the action carried out by the backhoe, and examples of the work content include bucket movement, turning of an upper turning body (main body portion) between the target object to be excavated and a loaded object, excavation (determination of an excavation point (excavation position), bucket movement to the excavation position, shoveling of the target object, and lifting), release of earth and sand, leveling, and the like. Note that the work content is different from an action that follows the trajectory generated by the trajectory generation unit and means the content of work that is the purpose of the work machine. An action control signal for carrying out action control for the content of the work is separately generated. That is, the action control signal corresponding to the action to be carried out next is transmitted to the controller 44. Specifically, determination of an excavation point (excavation position), bucket movement to the excavation position, shoveling of the target object, lifting, and the like are carried out in accordance with information on the position of the target object, and a next action control signal is generated.
The action control unit 153 generates a control signal for controlling the backhoe 40 so that the movable part moves along the generated trajectory and transmits the control signal to the controller 44.
Next, an example of work carried out by the backhoe 40 will be described.
Details of the leveling work will be described with reference to
As illustrated in 801 of
Next, as illustrated in 802 of
Next, in a case where a predetermined condition has been satisfied, the determination unit 120A determines that contact between the bucket 43 and the earth and sand TO has occurred and transmits a determination result to the action control apparatus 150. Upon receiving the determination result that contact between the bucket 43 and the earth and sand TO has occurred, the action control apparatus 150 stops the lowering control. Then, for example, the action control apparatus 150 starts raising control for raising the bucket 43 along a new raising trajectory ORB. As a result, as illustrated in 803 of
At the time t1, the action control apparatus 150 having acquired information indicating that the height of the bucket 43 is lower than 2.7 (m), which is the control target point, changes the height of the control target point to 1.58 (m), and further sets the lowering speed to v1 that is greater than v0. Thus, the bucket 43 continues lowering at the lowering speed v1 from t1. Note that there is a slight time difference until movement based on the control actually appears after the control is started.
From time t2 onwards, the lowering speed of the bucket 43 becomes slow and is changed to v2. This means that the bottom surface of the bucket 43 has come into contact with the earth and sand TO. Assume that the lowering speed v2 from t2 onwards is equal to or less than the threshold value vt of the amount of change in the position set in advance as the determination criterion for contact determination. Then, the lowering speed between t2 and t3 is equal to or less than the threshold value vt. The threshold value vt is set to, for example, 0.2 (m/sec). Although the threshold value vt is the lowering speed of the bucket 43, the threshold value vt may be specified by, for example, a turning angular speed of the boom 41. The threshold value of the turning angular speed of the boom 41 can be set to, for example, 1 (°/sec) in a downward direction.
Furthermore, a time period from t2 to t3 is a time period T that is set in advance as a determination criterion for contact determination. That is, it means that the amount v2 of change in the position is equal to or less than the threshold value vt for the time period T. The time period T is set to, for example, 0.5 (seconds).
In a case where the lowering speed of the bucket 43 becomes equal to or less than the set threshold value vt for the predetermined time period T, the determination unit 120A determines that contact between the bucket 43 and the earth and sand TO has occurred and transmits a determination result to the action control apparatus 150. The action control apparatus 150 having received the determination result stops the control for lowering the bucket 43. Therefore, there is little change in the height of the bucket 43 from t3 onwards. Note that, although the height of the bucket 43 is slightly lowered due to, for example, collapse of the earth and sand, the control for lowering the bucket 43 is not carried out.
Although the above-described amount of change in the position has been exemplified by the lowering speed, the amount of change in the position is not limited to the translational speed, and a translational acceleration, a turning angular speed, a turning angular acceleration, or the like may be used. Note, however, that since the calculation of the acceleration involves a large error caused by noise of a sensor signal, it is preferable to reduce the noise with use of, for example, a filter.
As described above, in the contact determination system 1A in accordance with the present example embodiment, a configuration is employed in which the action control apparatus 150 includes a trajectory generation unit 152 that generates a target trajectory of at least one movable part among one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part. That is, in the middle of the movement of the movable part along the generated target trajectory, whether the movable part has come into contact with the target object is determined. Thus, according to the contact determination system 1A in accordance with the present example embodiment, there is no risk of failure of the movable part to reach the target object. Further, the risk of the movable part continuing to move even after the movable part has come into contact with the target object is reduced. Therefore, it is possible to stop the movable part at an appropriate position. Thus, the effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
An action control method for a work machine as described above will be described with reference to the drawing.
As illustrated in
In step S132, the trajectory generation unit 152 generates the target trajectory. Specifically, the trajectory generation unit 152 generates the target trajectory that extends deep into the target object below the surface of the target object when viewed from at least one movable part. For example, in the case where the backhoe carries out earth and sand shaping work with use of the bucket, the trajectory generation unit 152 generates a target trajectory that extends deep into (inside) the earth and sand below the surface of the earth and sand when viewed from the bucket, with reference to the position information of the earth and sand.
In step S133, the action control unit 153 carries out action control of the bucket. Specifically, the action control unit 153 generates an action control signal for moving the bucket along the target trajectory and transmits the action control signal to the controller of the backhoe. The controller carries out control for moving the bucket on the basis of the received action control signal.
In step S134, the action control unit 153 determines whether the determination result that contact between the work machine and the target object has occurred is received from the contact determination device 100A. Note that the contact determination process carried out by the contact determination apparatus 100A will be described later.
In a case where the determination result that contact between the work machine and the target object has occurred is not received (NO in step S134), the flow returns to step S133.
In a case where the determination result that contact between the work machine and the target object has occurred is received (YES in step S134), the flow proceeds to step S135. In step S135, the action control unit 153 terminates the action control of the bucket (stops the bucket). This is the end of the action control process. Note that, in a case where it is determined that the contact has occurred, and the control for moving the bucket 43 along the target trajectory is terminated, a next action control may be carried out. For example, in the case of the work of leveling the earth and sand, the leveling work may be carried out after the bucket 43 is raised and moved to a next leveling position. In the case where next work content of the backhoe is not notified, the posture of the backhoe may be shifted to a posture of putting the bucket on the ground for standby.
By the above-described action control method, it is possible to shape a placed target object into a desired shape with use of the work machine.
Next, a contact determination method S100A of determining whether contact between the work machine and the target object has occurred will be described with reference to the drawing.
As illustrated in
In step S112, the acquisition unit 110 stores the acquired position of the movable part. Specifically, the acquisition unit 110 records, as sequential movable part position information MPI, the acquired detection value in the storage unit 130.
In step S121, the amount-of-change calculation unit 121 of the determination unit 120A acquires, from the position information recorded in the storage unit 130, the current movable part position information and the movable part position information one unit time before.
In step S122, the amount-of-change calculation unit 121 calculates the amount of change in the movable part position per unit time from the acquired movable part position information. For example, the amount-of-change calculation unit 121 calculates the movement speed of the movable part by subtracting the movable part position one unit time before from the current movable part position and dividing a difference by the unit time.
In step S123, the contact determination unit 123 determines whether the calculated amount of change is equal to or less than the threshold value. For example, the contact determination unit 123 determines whether the calculated movement speed is equal to or less than the threshold value recorded in the storage unit 130. This threshold value may be set in accordance with work content of the work machine or the target object. Examples of the work content include compacting earth and sand loaded on a dump truck until the surface height of the earth and sand loaded on the dump truck becomes lower than the height of a dump vessel (frame), making the maximum height difference between the bumps and dips on the surface of the earth and sand equal to or less than a predetermined value, and the like. For example, the threshold value may be set in consideration of the strength of a loading point. In the case of the work of compacting the earth and sand loaded on the dump truck, the threshold value is set to be small (for example, 0.1 m/s) in consideration of the strength of the dump truck. On the other hand, in the case of, like landfill work, the work of compacting the earth and sand loaded in a loading area, the threshold value may be set to be large (for example, 0.2 m/s). Examples of the target object include earth and sand, crushed stone, industrial waste, and the like.
In step S123, in a case where it is determined that the calculated amount of change is not equal to or less than the threshold value (NO in S123), the process proceeds to step S125. Then, in step S125, the elapsed time of which measurement has been started from the current time is reset, and the process returns to step S111.
In step S123, in a case where it is determined that the calculated amount of change is equal to or less than the threshold value (YES in S123), the process proceeds to step S124. In step S124, the elapsed time calculation unit 122 updates the elapsed time, and the flow proceeds to step S126.
In step S126, the elapsed time calculation unit 122 determines whether the elapsed time is equal to or more than a threshold value. The threshold value described here refers to the above-described time period T set in advance. This threshold value may be set in accordance with work content of the work machine or the target object. In step S126, in a case where it is determined that the elapsed time is not equal to or more than the threshold value (NO in S126), the process returns to step S111. At this time, the elapsed time is not reset.
In step S126, in a case where it is determined that the elapsed time is equal to or more than the threshold value (YES in S126), the process proceeds to step S127, the contact determination unit 123 determines that contact between the movable part and the target object has occurred. This is the end of the contact determination process. This determination result is transmitted to the action control apparatus 150.
As described above, in the contact determination method in accordance with the present example embodiment, a configuration is employed in which the amount of change in the position of the movable part is calculated on the basis of the position information of the movable part, and whether contact between the movable part and the target object has occurred is determined by comparing the amount of change with a set threshold value. That is, in the middle of the movement of the movable part along the generated target trajectory, whether the movable part has come into contact with the target object is determined in the above-described method. Thus, according to the contact determination method in accordance with the present example embodiment, there is no risk of failure of the movable part to reach the target object. Further, the risk of the movable part continuing to move even after the movable part has come into contact with the target object is reduced. Therefore, it is possible to stop the movable part at an appropriate position. Thus, the effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
Next, a first modification of the contact determination method in accordance with the second example embodiment will be described with reference to the drawing.
As illustrated in
First, the target object position acquisition unit 151 of the action control apparatus 150 acquires position information of the bucket 43 to be brought into contact with the surface of the ground and position information of the surface of the ground with which the bucket 43 is to be brought into contact. Next, the trajectory generation unit 152 generates a target trajectory in which an end point of the target trajectory is set to a position to which the bucket 43 goes deep into (inside) the ground below the surface of the ground. The reason for setting the end point to the position to which the bucket 43 goes deep into (inside) the ground below the surface of the ground is that, when the target trajectory is generated with the end point set to the position on the surface of the ground, there is a risk that the end point may be set to a position at which the bucket 43 does not come into contact with the surface of the ground due to, for example, an error in measurement of the position of the surface of the ground. The end point only needs to be a position slightly deep into (inside) the ground below the surface of the ground. For example, in a case where the backhoe 40 is a 30-ton class backhoe, the end point can be a position located at a depth of 20 cm in the ground.
Next, the action control unit 153 generates an action control signal for moving the bucket 43 along the generated target trajectory and transmits the action control signal to the controller 44. The controller 44 having received the action control signal carries out control for moving the bucket 43 in accordance with the action control signal.
The control for moving the bucket 43 is carried out by, for example, changing the turning angle of the boom shaft 46 so that the turning angle of the boom 41 with respect to the surface of the ground becomes small. Then, the determination unit 120A calculates the amount of change in the turning angle from the turning angle information of the boom shaft 46, determines that the bucket 43 has come into contact with the surface of the ground in a case where the calculated amount of change is less than the threshold value of the set amount of change, and transmits the determination result to the action control apparatus 150. In response to this, the action control apparatus 150 terminates the ground contact action control.
The threshold value in this case is a threshold value for determining that the bucket 43 no longer moves, and thus only needs to be, for example, an amount smaller than the controlled amount of change. By controlling in this way, it is possible to accurately carry out ground contact work of the bucket 43.
Next, a second modification of the contact determination method in accordance with the second example embodiment will be described with reference to the drawing.
In the second modification, in a case where the earth and sand TO is excavated or shaped with use of the bucket 43, determination of contact between the bucket 43 and the earth and sand TO is carried out.
In a case where the earth and sand TO is excavated or shaped, work of inserting a blade portion (or a tooth portion) 43b at the tip of the bucket 43 into the earth and sand TO is carried out. At this time, if the amount of insertion of the blade portion 43b into the earth and sand TO is small, excavation or shaping is not sufficiently carried out. Conversely, if the amount of insertion of the blade portion 43b into the earth and sand TO is too large, there is a risk that the bucket 43 may not move, or the front part of the backhoe 40 may be lifted up. Therefore, it is necessary to insert the bucket 43 into the earth and sand TO by an appropriate amount. In such a case, determination of contact between the bucket 43 and the earth and sand TO is carried out so that the blade portion 43b can be inserted into the earth and sand TO at an appropriate position.
First, the target object position acquisition unit 151 of the action control apparatus 150 acquires position information of the bucket 43 to be inserted into the earth and sand TO and position information of the surface of the earth and sand TO. Next, the trajectory generation unit 152 generates a target trajectory in which an end point of the target trajectory is set to a position to which the blade portion 43b goes deep into (inward of) the earth and sand TO below the surface of the earth and sand TO. The end point only needs to be a position sufficiently deep into (inside) the ground below the surface of the ground. For example, in a case where the backhoe 40 is a 30-ton class backhoe, the end point can be a position located at a depth of 2 m in the ground.
Next, the action control unit 153 generates an action control signal for moving the bucket 43 along the generated target trajectory and transmits the action control signal to the controller 44. The controller 44 having received the action control signal carries out control for moving the bucket 43 in accordance with the action control signal. At this time, the orientation of the bucket 43 is set such that the blade portion 43b faces the surface of the earth and sand TO.
The control for moving the bucket 43 is carried out by, for example, changing the turning angle of the arm shaft 47 so that the bucket 43 approaches the earth and sand TO. Then, the determination unit 120A calculates the amount of change in the turning angle from the turning angle information of the arm shaft 47, determines that the bucket 43 has been appropriately inserted into the earth and sand TO in a case where the calculated amount of change is less than the threshold value of the set amount of change, and transmits the determination result to the action control apparatus 150.
In response to this, the action control apparatus 150 terminates the insertion action control, and starts, for example, excavation action control for turning the bucket 43 or leveling action control for moving the bucket 43 back and forth.
The threshold value in this case is set on the basis of the amount of change, measured in advance, in the position in a case where the bucket 43 has been appropriately inserted into the earth and sand TO. By controlling in this way, it is possible to accurately carry out work of inserting the bucket 43 into the earth and sand TO.
A third example embodiment of the present invention will be described in detail with reference to the drawing. The same reference numerals are given to constituent elements which have functions identical with those described in the first and second example embodiments, and descriptions as to such constituent elements are not repeated.
The contact determination apparatus 100B and the action control apparatus 150 are connected to a backhoe 40, which is a work machine, via a communication network 50 so that information communication can be carried out. The backhoe 40 includes the controller 44. The communication network 50 and the backhoe 40 have configurations similar to those of the communication network 50 and the backhoe 40 described in the first example embodiment. In the present example embodiment as well, the contact determination system 1B, as described in the second example embodiment, can be used, as an example, when the backhoe 40 carries out the work of leveling earth and sand loaded on the dump truck 60.
The contact determination apparatus 100B includes an acquisition unit 110, a determination unit 120B, and a storage unit 130. The acquisition unit 110 acquires a signal transmitted from a sensor which is mounted on the backhoe 40. The sensor detects at least one piece of information selected from the group consisting of a turning angle and an amount of translation, which are pieces of information pertaining to a position of a movable part of the backhoe 40, and transmits the at least one piece of information to the acquisition unit 110.
The acquisition unit 110 further acquires information pertaining to work content of the backhoe 40 or a target object targeted for work of the backhoe 40. These pieces of information are referred to when a threshold value setting unit 124 described later sets at least one selected from the group consisting of a threshold value and a time period.
The determination unit 120B determines whether the movable part has come into contact with the target object. The determination unit 120B includes an amount-of-change calculation unit 121, an elapsed time calculation unit 122, a contact determination unit 123, and a threshold value setting unit 124. The amount-of-change calculation unit 121, the elapsed time calculation unit 122, and the contact determination unit 123 have the same configurations as those of the amount-of-change calculation unit 121, the elapsed time calculation unit 122, and the contact determination unit 123 described in the second example embodiment. The threshold value setting unit 124 sets at least one selected from the group consisting of a threshold value of the amount of change in the position and a time period in accordance with the work content of the backhoe 40 which is acquired by the acquisition unit 110 or the target object targeted for work which is acquired by the acquisition unit 110. The threshold value setting unit 124 is a form of the setting means recited in the claims.
Note that the threshold value setting unit 124 may be a threshold value setting model that receives, as input data, various conditions such as work content and work conditions and is learned through machine learning to output the optimum threshold value. For example, the threshold setting model may be learned with use of training data that is prepared by acquiring, for example, data indicating what degree of amount of change in the position of the movable part makes a skilled person decide to terminate the operation for moving the movable part when the skilled person actually carries out work with use of a work machine under the conditions of varying types and properties of the target object, and the like.
The storage unit 130 records movable part position information MPI and threshold value information THI. The movable part position information MPI is as described in the second example embodiment. The threshold value information THI is information pertaining to at least one selected from the group consisting of the threshold value and the time period which are set by the threshold value setting unit 124.
The threshold value and the time period are set in advance in accordance with the type of the work machine, the work content of the work machine, the properties of the target object targeted for work, the work environment, and the like. Therefore, at least one selected from the group consisting of the threshold value and the time period is paired with such various conditions and is recorded as the threshold value information THI in the storage unit 130.
The action control apparatus 150 includes the target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153. The target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153 have the same configurations as those of the target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153 described in the second example embodiment.
As described above, in the contact determination system 1B in accordance with the present example embodiment, the acquisition unit 110 further acquires information pertaining to work content of the work machine or the target object. Furthermore, a configuration is employed in which the determination unit 120B further includes the threshold value setting unit 124 that sets at least one selected from the group consisting of a threshold value and a time period in accordance with the work content or the target object acquired by the acquisition unit 110. Therefore, according to the contact determination system 1B in accordance with the present example embodiment, it is possible to carry out determination of contact between the work machine and the target object by comparing the amount of change in the position of the movable part with at least one selected from the group consisting of the threshold value and the time period. In addition, the threshold value or the time period is set with reference to the information pertaining to the work content of the work machine or the target object. Therefore, according to the contact determination system 1B in accordance with the present example embodiment, an effect of making it possible to determine whether contact between the movable part and the target object has occurred with high accuracy is obtained, compared to a method of detecting the position of the target object, calculating a distance between the movable part and the target object, and determining whether contact between the movable part and the target object has occurred on the basis of whether the movable part has moved that distance.
A fourth example embodiment of the present invention will be described in detail with reference to the drawing. The same reference numerals are given to constituent elements which have functions identical with those described in the first to third example embodiments, and descriptions as to such constituent elements are not repeated.
The contact determination apparatus 100C includes an acquisition unit 110, a determination unit 120C, and a storage unit 130. The acquisition unit 110 acquires a signal transmitted from a sensor which is mounted on the backhoe 40. The sensor detects at least one piece of information selected from the group consisting of a turning angle and an amount of translation, which are pieces of information pertaining to a position of a movable part of the backhoe 40, and transmits the at least one piece of information to the acquisition unit 110.
The contact determination apparatus 100C is connected to a backhoe 40, which is a work machine, via a communication network 50 so that information communication can be carried out. The backhoe 40 includes the controller 44. The communication network 50 and the backhoe 40 have configurations similar to those of the communication network 50 and the backhoe 40 described in the first example embodiment. In the present example embodiment as well, the contact determination apparatus 100C, as described in the second example embodiment, can be used, as an example, when the backhoe 40 carries out the work of leveling earth and sand loaded on the dump truck 60.
The determination unit 120C includes an amount-of-change calculation unit 121, an elapsed time calculation unit 122, a contact determination unit 123, a threshold value setting unit 124, a target object position acquisition unit 151, a trajectory generation unit 152, and an action control unit 153.
The amount-of-change calculation unit 121, the elapsed time calculation unit 122, the contact determination unit 123, and the threshold value setting unit 124 have the same configurations as those of the amount-of-change calculation unit 121, the elapsed time calculation unit 122, the contact determination unit 123, and the threshold value setting unit 124 that are included in the determination unit 120B described in the third example embodiment.
The target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153 have the same configurations as those of the target object position acquisition unit 151, the trajectory generation unit 152, and the action control unit 153 that are included in the action control apparatus 150 described in the third example embodiment.
That is, the contact determination apparatus 100C in accordance with the present example embodiment has a configuration in which the constituent components of the action control apparatus 150 are included in the determination unit 120B of the contact determination apparatus 100B described in the third example embodiment.
As described above, in the contact determination apparatus 100C in accordance with the present example embodiment, the following configuration is employed. That is, the trajectory generation unit 152 generates a target trajectory of at least one movable part among one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part. The action control unit 153 generates an action control signal for moving the movable part along the target trajectory. In the middle of the movement, the contact determination unit 123 determines that the movable part has come into contact with the target object in a case where the amount of change in the position of the movable part is equal to or less than the threshold value set by the threshold value setting unit 124. Then, the action control unit 153 generates an action control signal for stopping the movement of the movable part.
According to the above configuration, in the middle of the movement of the movable part along the generated target trajectory, whether the movable part has come into contact with the target object is determined. Thus, there is no risk of failure of the movable part to reach the target object. Further, the risk of the movable part continuing to move even after the movable part has come into contact with the target object is reduced. Therefore, it is possible to stop the movable part at an appropriate position. Thus, the effect of allowing a placed target object to be shaped into a desired shape with use of the work machine is obtained.
A fifth example embodiment of the present invention will be described in detail with reference to the drawing. The same reference numerals are given to constituent elements which have functions identical with those described in the first to fourth example embodiments, and descriptions as to such constituent elements are not repeated.
The configurations of the storage unit 140, the action control apparatus 150, and the communication network 50 are the same as those of the storage unit 140, the action control apparatus 150, and the communication network 50 described in the second example embodiment.
The backhoe 40 includes a controller 44 and a contact determination apparatus 100. The contact determination apparatus 100 has a configuration as described in the first example embodiment. The contact determination apparatus 100 and the controller 44 are connected to the storage unit 140 and the action control apparatus 150 via the communication network 50 so that information communication can be carried out.
The acquisition unit 11 of the contact determination apparatus 100 acquires information indicating at least one selected from the group consisting of a rotational position of the movable part of the backhoe 40 and a translational position of the movable part of the backhoe 40. These pieces of information are detected by a sensor(s) (not illustrated) and transmitted to the acquisition unit 11 in a wired or wireless manner. The determination unit 12 of the contact determination apparatus 100 carries out contact determination of contact between the backhoe 40 and earth and sand, which is the target object, on the basis of a result of a comparison between the amount of change in the position of the movable part of the backhoe 40 and a threshold value set in advance. The result of the contact determination is transmitted to the action control unit 153 of the action control apparatus 150 via the communication network 50. In a case where the action control unit 153 has received a determination result that contact between the backhoe 40 and the earth and sand has occurred, the action control unit 153 generates an action control signal for stopping the movement control of the movable part of the backhoe 40 and transmits the action control signal to the controller 44.
As described above, according to the contact determination system in accordance with the present example embodiment, a configuration is employed in which the backhoe 40, which is the work machine, includes the contact determination apparatus 100. This allows a placed target object to be shaped into a desired shape with use of the work machine.
In the fifth example embodiment, the contact determination apparatus 100 included in the backhoe 40 is the contact determination apparatus 100 described in the first example embodiment, and includes an acquisition unit 11 and a determination unit 12. However, the contact determination apparatus included in the backhoe 40 is not limited to the contact determination apparatus 100 described in the first example embodiment, and may be the contact determination apparatus 100A, the contact determination apparatus 100B, or the contact determination apparatus 100C, which are described in the second, third, and fourth example embodiments, respectively. In that case, the storage unit 140 illustrated in
Some or all of functions of the contact determination apparatuses 100, 100A, 100B, and 100C (hereinafter referred to as “contact determination apparatus 100 or the like”) can be realized by hardware such as an integrated circuit (IC chip) or can be alternatively realized by software.
In the latter case, the contact determination apparatus 100 or the like is realized by, for example, a computer that executes instructions of a program that is software realizing the foregoing functions.
As the processor C1, for example, it is possible to use a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), a micro processing unit (MPU), a floating point number processing unit (FPU), a physics processing unit (PPU), a microcontroller, or a combination of these. As the memory C2, for example, it is possible to use a flash memory, a hard disk drive (HDD), a solid state drive (SSD), or a combination of these.
Note that the computer C can further include a random access memory (RAM) in which the program P is loaded when the program P is executed and in which various kinds of data are temporarily stored. The computer C can further include a communication interface for carrying out transmission and reception of data with other apparatuses. The computer C can further include an input-output interface for connecting input-output apparatuses such as a keyboard, a mouse, a display, and a printer.
The program P can be stored in a non-transitory tangible storage medium M which is readable by the computer C. The storage medium M can be, for example, a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like. The computer C can obtain the program P via the storage medium M. The program P can be transmitted via a transmission medium. The transmission medium can be, for example, a communications network, a broadcast wave, or the like. The computer C can obtain the program P also via such a transmission medium.
The present invention is not limited to the foregoing example embodiments, but may be altered in various ways by a skilled person within the scope of the claims. For example, the present invention also encompasses, in its technical scope, any example embodiment derived by appropriately combining technical means disclosed in the foregoing example embodiments.
Some of or all of the foregoing example embodiments can also be described as below. Note, however, that the present invention is not limited to the following example aspects.
A contact determination method including: acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it possible to reliably carry out the determination of the contact. Thus, it is possible to shape a placed target object into a desired shape with use of the work machine.
The contact determination method of supplemental note 1, further including calculating the amount of change in the position.
According to the above-described configuration, the amount of change in the position is calculated, and the determination of the contact is carried out on the basis of the calculated amount of change in the position. Thus, it is possible to reliably carry out the determination of the contact.
The contact determination method according to supplementary note 1 or 2, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value.
According to the above-described configuration, the amount of change in the position is compared with a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. By setting the threshold value in advance by determining an appropriate amount of change in the position in an experiment or the like, it is possible to more reliably carry out the contact determination.
The contact determination method according to supplementary note 3, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value in a time period that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, in the time period that serves as a criterion on which to determine contact between the work machine and the target object, the amount of change in the position is compared with the threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object. Thus, even when the amount of change becomes equal to or less than the threshold value due to an accidental event, the contact determination is not affected. Therefore, it is possible to more reliably carry out the contact determination.
The contact determination method according to supplementary note 4, further including: further acquiring information pertaining to work content of the work machine or the target object; and setting, in accordance with the work content or the target object, at least one selected from the group consisting of the threshold value and the time period.
According to the above-described configuration, at least one selected from the group consisting of the threshold value and the time period is set with reference to the information pertaining to the work content of the work machine or the target object. Therefore, it is possible to more reliably carry out the contact determination.
The contact determination method according to any one of supplementary notes 1 to 5, wherein the at least one movable part is any movable part selected from the group consisting of a first movable part connected to a main body of the work machine, a second movable part connected to the first movable part, and a third movable part connected to the second movable part, and in the step of acquiring the information pertaining to the position of the at least one movable part, information pertaining to a rotational position of the at least one movable part is acquired.
According to the above-described configuration, it possible to more reliably carry out the determination of contact between the rotating movable part of the work machine and the target object.
The contact determination method according to any one of supplementary notes 1 to 5, further including generating a target trajectory of the at least one movable part among the one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part.
According to the above-described configuration, it is possible to inhibit an event in which the movable part does not reach the target object or an event in which the movable part is excessively pressed against the target object.
A contact determination system including: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 1.
The contact determination system according to supplementary note 8, further including a calculation means for calculating the amount of change in the position.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 2.
The contact determination system according to supplementary note 8 or 9, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 3.
The contact determination system according to supplementary note 10, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value in a time period that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 4.
The contact determination system according to claim 11, wherein the acquisition means further acquires information pertaining to work content of the work machine or the target object, and said contact determination system further includes a setting means for setting, in accordance with the work content or the target object, at least one selected from the group consisting of the threshold value and the time period.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 5.
The contact determination system according to any one of supplementary notes 8 to 12, wherein the at least one movable part is any movable part selected from the group consisting of a first movable part connected to a main body of the work machine, a second movable part connected to the first movable part, and a third movable part connected to the second movable part, and the acquisition means acquires information pertaining to a rotational position of the at least one movable part.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 6.
The contact determination system according to any one of supplementary notes 8 to 13, further including an action control means for generating a target trajectory of the at least one movable part among the one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 7.
A contact determination apparatus including: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 1.
The contact determination apparatus according to supplementary note 15, further including a calculation means for calculating the amount of change in the position.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 2.
The contact determination apparatus according to supplementary note 15 or 16, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 3.
The contact determination apparatus according to supplementary note 17, wherein the determination criterion for the contact determination includes a criterion that the amount of change in the position is equal to or less than the threshold value in a time period that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 4.
The contact determination apparatus according to supplementary note 18, wherein the acquisition means further acquires information pertaining to work content of the work machine or the target object, and said contact determination apparatus further includes a setting means for setting, in accordance with the work content or the target object, at least one selected from the group consisting of the threshold value and the time period.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 5.
The contact determination apparatus according to any one of supplementary notes 15 to 19, wherein the at least one movable part is any movable part selected from the group consisting of a first movable part connected to a main body of the work machine, a second movable part connected to the first movable part, and a third movable part connected to the second movable part, and the acquisition means acquires information pertaining to a rotational position of the at least one movable part.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 6.
The contact determination apparatus according to any one of supplementary notes 15 to 20, further including an action control means for generating a target trajectory of the at least one movable part among the one or more movable parts, the target trajectory extending deep into the target object below a surface of the target object when viewed from the at least one movable part.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 7.
A program for causing a computer to function as a contact determination apparatus, the program causing the computer to function as: an acquisition means for acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination means for carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
According to the above-described configuration, it is possible to obtain the same effect as the effect brought about by supplementary note 1.
Furthermore, some of or all of the foregoing example embodiments can also be described as below.
A contact determination apparatus including at least one processor, the at least one processor carrying out: an acquisition process of acquiring information pertaining to a position of at least one movable part among one or more movable parts provided in a work machine; and a determination process of carrying out determination of contact between the work machine and a target object on a basis of a result of a comparison between an amount of change in the position of the at least one movable part specified in accordance with the information pertaining to the position and a threshold value indicating an amount of change that serves as a criterion on which to determine contact between the work machine and the target object.
Note that this contact determination apparatus can further include a memory. The memory can store a program for causing the processor to execute the acquisition process and the determination process. The program can be stored in a computer-readable non-transitory tangible storage medium.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/033414 | 9/10/2021 | WO |
