Patent Application
20250003180
The present disclosure generally relates to mobile construction equipment, such as a motor grader, and more particularly to using the mobile construction equipment to establish proper cross slope of a surface, such as a road, despite changes in a longitudinal slope of the road.
Construction equipment, such as a motor grader, can be used for road work, ditch work, site preparation, and other surface contouring and finishing tasks. Using a work implement, such as a blade assembly. the motor grader can impart a cross slope section and/or a longitudinal slope section on the road on which it is operating. Cross slope grade is the transverse slope of the road surface, extending laterally and measured relative to the horizon. Cross slope grade measures the crown of a road, which generally includes a high point at the center and downwardly-sloping sides when viewed as a lateral cross section. Proper cross slope grade provides a gradient for water runoff into a drainage system such as a street gutter or ditch. Maintaining the proper cross slope grade of a road is important for water drainage and safe operation of vehicles on the road. particularly in mining and construction environments. Longitudinal slope grade, by comparison, is the slope of the road with respect to the direction of travel relative to the horizon. Longitudinal slope grade measures the grade of the road over a distance traveled, which affects the load on work machines carrying heavy cargo. While a motor grader can impart a longitudinal slope section on a road, the road may instead already have an existing longitudinal slope section prior to the motor grader working the surface of the road.
Rear wheels 22 are operatively supported on tandem axles 24, which are pivotally connected to motor grader 10 between rear wheels 22 on each side of motor grader 10. The power source may be. for example, a diesel engine, a gasoline engine, a natural gas engine, or any other engine. The power source may also be an electric motor linked to a fuel cell, capacitive storage device. battery, or another source of power. The transmission may be a mechanical transmission, hydraulic transmission, or any other transmission type. The transmission may be operable to produce multiple output speed ratios (or a continuously variable speed ratio) between the power source and driven traction devices. Motor grader 10 also includes an articulation joint 62 that pivotally connects front frame 12 and rear frame 14, such that front frame 12 can pivot relative to rear frame 14 about an articulation axis B to help facilitate steering of motor grader 10.
Front frame 12 typically supports an operator station 26 that contains operator controls, along with one or more user interfaces 27 for conveying information to the operator for operation of motor grader 10 or inputting information. For example, motor grader 10 may include a machine speed sensor 90, which could be any sensor configured to monitor machine speed V, including sensors associated with any of the front wheels 58, 60, rear wheels 22. axle shafts, motors. or other components of the drivetrain of motor grader 10. Machine speed V could be displayed on user interface 27 within operator station 26.
Motor grader 10 may also work in conjunction with a global navigation satellite system, or GNSS. A GNSS is a satellite navigation system with global coverage that can be used to provide autonomous geo-positioning of objects associated with the GNSS, such as an autonomously operated motor grader. One example of a GNSS is a global positioning system. or GPS. The GNSS may include a satellite positioning unit 88 disposed on motor grader 10. Satellite positioning unit 88 generates signals indicative of location L of motor grader 10 (e.g., on road 100). Satellite positioning unit 88 may determine and generate signals corresponding to the latitude and/or longitude of motor grader 10. Satellite positioning unit 88 may be disposed on a top portion of motor grader 10 (e.g., on operator station 26, as shown in
Front frame 12 may also include a beam 28 that supports blade assembly 18 and is employed to move blade 30 to a wide range of positions relative to motor grader 10 (e.g., to impart on road 100 cross slope section 108, fore slope section 110, back slope section 112, and/or longitudinal slope section 116 at one more grades G). As shown in
Drawbar 32 may include a large, flat plate, commonly referred to as a yoke plate 42. Beneath yoke plate 42 is a circular gear arrangement and mount, commonly referred to as a circle 44. Circle 44 is rotated by, for example, a hydraulic motor referred to as a circle drive 46. Rotation of circle 44 by circle drive 46 rotates blade 30 about an axis A perpendicular to a plane of drawbar yoke plate 42. The blade cutting angle is defined as the angle of work implement 16 relative to a longitudinal axis 48 of front frame 12. For example, at a zero degree blade cutting angle, blade 30 is aligned at a right angle to longitudinal axis 48 of front frame 12 and beam 28, as shown in
Blade 30 is also mounted to circle 44 via a pivot assembly 50 that allows for tilting of blade 30 relative to circle 44. A blade tip cylinder 52 is used to tilt blade 30 forward or rearward. In other words, blade tip cylinder 52 is used to tip or tilt a top edge 54 of blade 30 relative to a bottom cutting edge 56 of blade 30, which is commonly referred to as a blade tip. Blade 30 is also mounted to a sliding joint associated with circle 44 that allows blade 30 to slide or shift from side-to-side relative to circle 44. The side-to-side shift is commonly referred to as blade side shift. A side shift cylinder or the like is used to control the blade side shift.
The foregoing components together allow for movement of blade 30 in a number of different manners, all of which can be used to impart, for example, one or more cross slope grades GCS on cross slope sections 108.
To impart cross slope grade GCS, motor grader 10 typically includes an automatic cross slope control system where the operator manually controls one side of blade 30 (e.g., first blade side 31A), while the other side of blade 30 (e.g., second blade side 31B) is automatically controlled, all resulting in blade 30 being positioned in a desired overall blade position P30 leading to a desired cross slope grade GCS.
Such automatic control of cross slope grade GCS is accomplished in part by determining overall blade position P30 using one or more sensors. For example, as shown in
Mainfall sensor 80 may be a single multi-axis inertial measurement unit configured to produce a signal indicative of the longitudinal pitch of motor grader 10 and a signal indicative of the lateral roll of motor grader 10. The longitudinal pitch of motor grader 10 may be equivalent to longitudinal slope grade GLS of longitudinal slope section 116 of road 100 on which motor grader 10 is situated. Inertial measurement units are self-contained sensor systems capable of generating signals indicative of linear and angular motion. A multi-axis inertial measurement unit includes two or more gyroscopes and accelerometers for measuring linear and angular motion in at least two dimensions (e.g., along two axes). The axes of the multi-axis inertial measurement unit are typically aligned with the longitudinal axis of motor grader 10 (e.g., longitudinal axis 48 of front frame 12) and the lateral axis of motor grader 10 to generate signals indicative of the longitudinal pitch and lateral roll of motor grader 10. respectively.
Rotation sensor 82 may be configured to produce a signal indicative of the angle of blade 30 relative to front frame 12 and the lateral axis of motor grader 10. Rotation sensor 82 produces a signal indicative of the direction of blade 30 relative to the direction of travel of motor grader 10 (e.g., along road 100).
Blade slope sensor 84 may be configured to produce a signal indicative lateral slope of blade 30. The axis of mainfall sensor 80 is aligned with the longitudinal axis of motor grader 10 (e.g., longitudinal axis 48 of front frame 12) to generate signals indicative of the longitudinal pitch of motor grader 10, while blade slope sensor 84 generates signals indicative of the lateral roll of motor grader 10 when blade 30 is aligned with a lateral axis of motor grader 10. The lateral slope of motor grader 10 may be equivalent to a target cross slope grade TGCS of blade 30 of motor grader 10, as discuss in more detail below.
Rotation sensor 82 can be used in conjunction with blade slope sensor 84 to determine the lateral roll of motor grader 10 when blade 30 is aligned with the lateral axis of motor grader 10. ensuring the signals from blade slope sensor 84 are measuring the slope of a surface that is perpendicular to the direction of travel of motor grader 10.
During maintenance of road 100, an operator of motor grader 10 may need to adjust cross slope grade GCS of cross slope section 108 while a longitudinal slope grade GLS of longitudinal slope section 116 is changing. For example, if longitudinal slope grade GLS is increasing, cross slope grade GCS may need to be decreased. Conversely, if longitudinal slope grade GLS is decreasing. cross slope grade GCS may need to be increased. However, implementing such control is complex, as it requires an operator to simultaneously steer motor grader 10, estimate longitudinal slope grade GLS, manually control one side of blade 30 (e.g., first blade side 31A), and manually change a target cross slope grade TGCS of blade 30 to implement a proper cross slope grade GCS. The complexity of this operation typically results in inconsistent cross slope grade GCS, incorrect cross slope grade GCS, and variation in carrying out the operation across different operators of motor grader 10.
One aspect of the present disclosure is directed to a mobile construction equipment for operation on a surface having at least one longitudinal slope grade, the mobile construction equipment comprising: a blade that is movable with respect to the mobile construction equipment. the blade having a first blade side and a second blade side opposite the first blade side, the blade being configured to impart at least one cross slope grade on the surface; and a controller configured to receive the at least one longitudinal slope grade. a first blade side position of the first blade side, and at least one target cross slope grade, and, based on the at least one longitudinal slope grade and the first blade side position, adjust a second blade side position of the second blade side so as to impart the at least one target cross slope grade on the surface.
Another aspect of the present disclosure is directed to a method for imparting at least one cross slope grade on a surface using a mobile construction equipment having a blade with a first blade side and a second blade side opposite the first blade side, the surface having at least one longitudinal slope grade, the method comprising: receiving the at least one longitudinal slope grade. a first blade side position of the first blade side, and at least one target cross slope grade; and based on the at least one longitudinal slope grade and the first blade side position. adjusting a second blade side position of the second blade side so as to impart the at least one target cross slope grade on the surface.
A further aspect of the present disclosure is directed to a controller for a mobile construction equipment having a blade that is movable with respect to the mobile construction equipment to impart at least one cross slope grade on a surface on which the mobile construction equipment is operating, the blade having a first blade side and a second blade side opposite the first blade side, the surface having at least one longitudinal slope grade, the controller being configured to: receive the at least one longitudinal slope grade; receive a first blade side position of the first blade side; receive at least one target cross slope grade; and based on the at least one longitudinal slope grade and the first blade side position. adjust a second blade side position of the second blade side so as to impart the at least one target cross slope grade on the surface.
The present application describes mobile construction equipment, methods, and controllers used to establish cross slope grade GCS of a surface, such as a road, in ways that compensate for the surface having a longitudinal slope grade GLS. In general. the mobile construction equipment may be a motor grader, such as motor grader 10. Motor grader 10 includes blade 30. which is movable with respect to motor grader 10 such that blade 30 can be used to impart or establish at least one cross slope section 108 having a cross slope grade GCS on a surface on which motor grader 10 is operating, such as road 100. When using an automatic cross slope control system, which automatically controls a second blade side 31B of blade 30 to impart a desired cross slope grade GCS on road 100 based on the operator manually controlling a first blade side 31A of blade 30, the mobile construction equipment, methods, and controllers of the present application avoid the shortcomings associated with the operator needing to take into account longitudinal slope grade GLS of road 100. By compensating for longitudinal slope grade GLS in this manner, the operator is able to focus on other tasks associated with implementing a desired cross slope grade GCS on road 100 (e.g., steering motor grader 10, manually controlling first blade side 31A, etc.).
Control system 94 may incorporate a number of inputs, such as inputs from mainfall sensor 80, rotation sensor 82, blade slope sensor 84, satellite positioning unit 88, machine speed sensor 90, a settings module 98, and/or a user interface 27. among others. Settings module 98 may store setting information relating to local conditions and the surroundings of motor grader 10, which vary. Exemplary setting information includes, for example, information related to configurations of motor grader 10 that are specific to road 100 on which motor grader 10 operates (e.g., road surface material, road design, etc.).
User interface 27 may be disposed within operator station 26 of motor grader 10 so that the operator of motor grader 10 can input information into controller 96. Alternatively, user interface 27 could be located remote from motor grader 10 (e.g., if motor grader 10 is being operated autonomously). Exemplary information that may be inputted via user interface 27 can include one or more longitudinal slope grades GLS of road 100 on which motor grader 10 is operating. Alternatively, one or more longitudinal slope grades GLS of road 100 on which motor grader 10 is operating may be inputted into controller 96 by mainfall sensor 80.
Other exemplary information that may be inputted via user interface 27 can include one or more target cross slope grade TGCS. A target cross slope grade TGCS is a desired grade of a particular location L on road 100. Different target cross slope grade TGCS may be associated with different locations L on road 100. For example, a first target cross slope grade TGCS1 may be associated with a first location L1 on road 100 (i.e., a first cross slope section 108), while a second target cross slope grade TGCS2 may be associated with a second location L2 on road 100 (i.e., a second cross slope section 108), second location L2being different than first location L1.
Under ideal conditions, a given target cross slope grade TGCS would be exactly the same as a cross slope grade GCS actually imparted by motor grader 10 on cross slope section 108 of road 100. However, in real-world conditions, a target cross slope grade TGCS, is, as its name suggests, a “target” for cross slope grade GCS. understanding that motor grader 10 may not be able to obtain an exact one-to-one correspondence between target cross slope grade TGCS and cross slope grade GCS actually imparted by motor grader 10 on road 100. Nevertheless, target cross slope grade TGCS and cross slope grade GCS imparted by motor grader 10 on road 100. can, in practice, be considered equal.
Based at least in part on received longitudinal slope grade GLS and target cross slope grade TGCS information (e.g., input using user interface 27), controller 96 can issue various instructions to control a second blade side position P31B of the second blade side 31B of blade 30 so as to impart the at least one target cross slope grade TGCS on road 100. In particular, since controller 96 also receives a first blade side position P31A of first blade side 31A. controller 96 can output instructions that result in second blade side 31B being moved to a particular second blade side position Par such that blade 30, which extends between first blade side 31A and second blade side 31B, imparts the at least one target cross slope grade TGCS on road 100. To move second blade side 31B accordingly. controller 96 can issue instructions to actuate one or more of right lift cylinder 36, left lift cylinder 38, center shift cylinder 40, circle drive 46, blade tip cylinder 52, and/or any other actuators for moving blade 30 to transition second blade side 31B to a position consistent with a particular target cross slope grade TGCS on road 100.
In addition to longitudinal slope grade Gus and target cross slope grade TGCS. controller 96 can also control second blade side position P31B based on other inputs, in that there may be at least one input into controller 96 in addition to one or more longitudinal slope grades Gus and one or more target cross slope grade TGCS, as shown in
Maps M1 and M2 are but two examples of possible correlations between longitudinal slope grade GLS and target cross slope grade TGCS. Other maps M are possible and considered to be within the scope of the present disclosure.
Progressing to
Moving to
In general, the mobile construction equipment, methods, and controllers of the present application are applicable for automatically compensating for longitudinal slope grade when grading a road to impart a particular cross slope grade. By inputting information that correlates at least one longitudinal slope grade with at least one target cross slope grade, the mobile construction equipment, methods, and controllers of the present application allow an operator of a motor grader to avoid needing to take into consideration one additional variable (i.e., longitudinal slope grade) when trying to impart cross slope grade on a road. By removing longitudinal slope grade from the operator's consideration, the operator can more effectively operate the motor grader to impart a proper cross slope grade on the road, which ultimately results in improved road quality (e.g., better drainage, longer life, etc.).
While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above and below. Additionally, statements made herein characterizing the invention refer to an embodiment of the invention and not necessarily all embodiments.
The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise. the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further. the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C.
The present disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.
