Patent Application
20110169949
The present invention relates to earth-moving vehicles and agricultural implements. In particular, the present invention relates to orienting an implement on a vehicle.
Earth-moving machines are used in various operations for road building, grading, building, mining, etc. Agricultural implements are used for various operations related to farming including plowing, seeding, spraying, harvesting, etc. In both situations, a vehicle having three or more wheels, or two or more treads, may have an implement attached. The implement may be a blade, scoop, hoe, plow, grader, or any other possible implement. The implement may be attached to the vehicle by one or more articulating arms, and may be rotatable in three dimensions. The position and angle of the implement may therefore be adjusted by an operator in the vehicle using hydraulic controls, or by any other appropriate control mechanism.
The location and angle of an implement have conventionally been determined based on a determination by an operator based on visual assessment. A demand for increased precision in many operations has arisen recently in order to reduce costs and/or improve quality of a finished product. Sensors have therefore been utilized to determine position and angle of an implement of a vehicle. However, due to the extreme circumstances under which these sensors must operate, a high failure rate and/or a low accuracy have been until now realized.
Global positioning systems (GPS) have been used to position people and vehicles. Additionally, GPS systems have been located on implements to provide location information for the implement. However, positioning the sensitive electronics related to a GPS on an implement may result in system failures and degraded position information.
A more accurate system and method for positioning an implement on a vehicle are therefore required.
A system for determining an orientation of an implement on a vehicle is provided. The system includes a camera mounted to the vehicle, and a target object within a field of vision of the camera and mounted to the implement. The target object includes markings to enable a determination of the orientation of the implement with respect to the camera. The target object may be a sphere, a grade rod, or any other appropriate object
A method of determining an orientation of an implement on a vehicle is provided. The method includes detecting at least one target object with at least one camera. The target object is mounted to the implement and includes markings. The method also includes determining the orientation of the implement using at least some of the markings.
A system of orienting an implement is provided that includes means for detecting at least one target object attached to the implement, and means for determining an intermediate orientation of the at least one target object with respect to the at least one camera using markings on the target object. The method also includes means for determining the orientation of the implement using the intermediate orientation of the target object.
A method of installing an implement orientation system is provided that includes mounting a camera on a vehicle having an implement, and mounting a target object to the implement within a field of vision of the camera, the target object including markings. The method also includes coupling the camera to a processor adapted to determine an orientation of the implement by determining an intermediate orientation of the target object with respect to the camera using at least some of the markings.
A computer-readable medium having stored thereon computer-executable instructions is provided. The computer-executable instructions cause a processor to perform a method of determining an orientation of an implement when executed.
These and other advantages of the invention will be apparent to those of ordinary skill in the art by reference to the following detailed description and the accompanying drawings.
The present invention addresses the aforementioned limitations in conventional earth-moving vehicles and agricultural implements by arranging a target object on the implement and arranging a camera directed at the target. A processor evaluating an image of the target determines a distance to, and orientation of, the target, and uses that information to determine a position and orientation of the implement.
The system may use cameras mounted on the cab or any other position on the vehicle. One or more cameras may be used, and one or more targets may be arranged on the implement. When using multiple cameras and multiple targets, each camera may have only one target in a field of vision, or each camera may have more than one target, or even all targets, arranged in a field of vision. The system and method may process only one imaged target, or each of the imaged targets when multiple targets are viewed by a camera. A camera may position a target by viewing a set of markings on the target. For instance, a target may be a sphere having a set of markings enabling the processor to determine the orientation of the sphere from the image.
Alternative exemplary embodiments of the instant invention provide that the target object (also referred to alternatively as the target) may be a sphere, an elliptical object, a rod or grade rod, or any other appropriate shape. The target object may be solid or hollow and may be composed of any appropriate material, including plastic or metal. The target object may have markings that may include distinctive shapes, different colors, or specific shape arrangements which may provide orientation information to the processor.
The desired position and orientation of the implement may include rotation about X, Y, and Z axes, as well as a distance and direction from the vehicle. Each of these rotations, distance, and direction of an implement may be manipulable by an operator of the vehicle using hydraulic control or other control mechanisms. Additionally, the processor determining position and orientation may be coupled to a display in the cab for viewing by an operator, or may have direct control of the implement. The processor or a dedicated control system may be adapted to direct the vehicle and implement either directly or indirectly in a stored work plan and/or toward a stored goal.
In the system, the target object includes markings to enable a determination of an orientation of the target object with respect to the camera, which is also referred to herein as an intermediate orientation. This intermediate orientation may be used by the processor to determine the orientation of the implement with respect to the camera using stored information relating to the mounting of the target object on the implement, including a distance and direction from the target object to the implement. When a second target object is used, a determination of a second intermediate orientation of the second target object with respect to the camera may be made.
A positioning system antenna may be mounted to the vehicle at a fixed distance in a fixed direction from the camera, and a positioning system receiver/processor may be coupled to the positioning system antenna. A control system may be adapted to adjust the orientation of the implement based on a desired orientation of the implement and the determination of the orientation of the implement.
A second camera with a second fixed distance and a second fixed orientation with respect to the positioning system may be used. The second camera may have a second field of vision including the target object, and the markings of the target object may enable a determination of a third intermediate orientation of the target object with respect to the second camera.
A processor may be electrically coupled to the positioning system receiver/processor and the camera and perform the determination of the intermediate orientation of the target object with respect to the camera based on the markings. The processor may be adapted to determine the second and third intermediate orientations, as appropriate. The processor may further be adapted to perform the determination of the orientation of the implement based on one or all of the intermediate orientation and the second and third intermediate orientations.
The positioning system receiver/processor is adapted to determine a vehicle position and a vehicle orientation in a world reference frame. For example, the reference frame used may be WGS 84 (the World Geodetic System of 1984). The determination of the intermediate orientation of the target object with respect to the camera may be in a vehicle reference frame. In other words, an origin of the reference frame may be fixed with respect to the vehicle, and the orientation of the target object may be with respect to the vehicle as well as the camera, since the camera may be fixed to the vehicle. In this case, the determination of the orientation of the implement may also be in the vehicle reference frame. The determination of the orientation of the implement in a vehicle reference and the vehicle orientation in the world reference frame may enable a determination of a further orientation of the implement in the world reference frame.
A data storage unit may be coupled to the processor. The processor may be adapted to determine a distance from the camera to the target object by comparing an image of the target object to information relating to a shape and a dimension of the target object stored in the data storage unit. A distance from the camera to an object may be determined by a size of the target in the image. A processor may determine distance to the target using image size information along with stored size information and lens information. Alternatively, the processor may use stored image files and compare them with the image to determine the distance. The camera may be mounted to the implement at a third fixed distance in a third fixed direction from the target object. The processor may be adapted to determine a position of the implement based on the distance determined by the processor between the camera and the target object, the third fixed distance, the third fixed direction, the vehicle position, and the vehicle orientation.
The implement may be an earth-moving implement and the vehicle may be an earth-moving machine. The positioning system receiver/processor and the camera may be mounted to a cab of the earth-moving machine.
The markings may include different shapes arranged on a surface of the target object, and identification of at least some of the different shapes may enable the determination of the orientation, as discussed in connection with
Camera 130 may output an image of target object 150 to a processor. The processor may determine an orientation of target object 150 and/or a distance to target object 150. The processor may determine therefrom an orientation and position of implement 120 with respect to the remainder of vehicle 100. The processor may further determine a global position and orientation of implement 120 based on global positioning information obtained from antenna 160 and a global positioning system.
Active light emitting diodes (LEDs, also referred to herein as active light elements) may be mounted on the one or more grade rods, or any other target discussed herein, including a sphere. The LEDs may emit infrared light, and may be point sources or may form any of the target shapes discussed herein. The LEDs may be viewed by one or more cameras mounted on a vehicle cab, for instance a dozer body. The cameras may be sensitive in the light spectrum, the infrared spectrum, both spectrums, or any other appropriate electromagnetic spectrum. Active LED targets using the infrared spectrum may provide several advantages over the visible spectrum, including improved viewing in dusty environments and inclement weather conditions.
One grade rod mounted on an implement, for example in the middle of an implement, with one or more LEDs or other markings arranged on it, may be sufficient for orientation. For example, if the grade rod is installed on a dozer on which only elevation and slope of the blade are automatically controlled, one rod with markings or LEDs will provide measurements of both blade elevation and blade slope, which is enough for blade control.
Additionally, LEDs may not have significant power consumption requirements, and therefore the LED system on the implement may be equipped with long-lasting batteries to eliminate power cables leading from the cab of the implement. An additional power source, such as photovoltaic solar cells on top of the rod, may be provided. In some modes using batteries and photovoltaic solar cells, when sunlight is significant, the LEDs may consume power from the solar cells and the batteries may simultaneously be charged from the solar cells. When sunlight is insufficient to operate the LEDs, the LEDs receive power from the batteries. In this manner, the batteries and solar cells complement each other as power sources, and there may be no need to replace the batteries.
A method of installing an implement orientation system may include mounting a camera on a vehicle having an implement and mounting a target object to the implement within a field of vision of the camera. The target object may include markings. The method may also include coupling the camera to a processor adapted to determine an orientation of the implement by determining an intermediate orientation of the target object with respect to the camera using at least some of the markings.
The method may include mounting a positioning system on the vehicle. The method may include mounting a second target object within a field of vision of the camera and attached to the implement. The second target object may include second markings. The processor may be adapted to determine a second intermediate orientation of the second target object using the second markings.
The method may include mounting a second camera on the vehicle and arranging the second camera to include the target object in a second field of vision. The method may include coupling the second camera to the processor. The processor may be adapted to determine the orientation of the implement by determining another intermediate orientation of the target object with respect to the second camera using at least some of the markings.
The installation method may also include downloading mounting information to a storage device coupled to the processor to enable the determination of orientation and position. The installation alternatively or additionally may include calibrating the camera and/or processor by obtaining images of the target object after mounting with the implement in known positions and orientations.
The foregoing Detailed Description is to be understood as being in every respect illustrative and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the Detailed Description, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. It is to be understood that the embodiments shown and described herein are only illustrative of the principles of the present invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention.
