Patent Application
20090265962
The present disclosure is directed to an avoidance system, and more particularly, an avoidance system for detecting and locating electric cables.
Earthmoving machines such as excavation-type machines, drilling machines, loaders, and the like may be employed for mining or other earthmoving operations. These machines employ large earthmoving, excavating, or drilling equipment, such as electric mining shovels, configured to dig and load earthen material from a worksite, such as an open-pit mine, to large off-road haulage units, such as off-highway trucks which may be autonomously or semi-autonomously controlled. The shovel may be electrically powered and receive power from large, high-voltage cables tethered to the rear of the machine. The electric cables may lie across the ground of the worksite or along a bench floor during operation of the shovel. As the shovel moves to a new location, for example, when the shovel swings between a work surface and an off-highway truck that it is loading, the cables are dragged across the ground and their location changes relative to the ground.
Off-highway trucks may navigate to and from the shovel location to transport the earthen material from the worksite. An operator of the off-highway truck must avoid contact with the electric cables so as to prevent damage to both the electric cables and the truck. However, mobility and navigation around the electric cables may be difficult because the operator may be unable to see the ground, and thus locate the electric cables, near the truck.
One method of locating obstacles for mining operations under such conditions is described in U.S. Pat. No. 6,064,926 (the '926 patent) to Sarangapani et al., issued on May 16, 2000. The '926 patent describes a method and an apparatus for planning an alternate path in response to detection of an obstacle by a mobile machine, such as an off-road mining truck, at a worksite. The method includes determining the presence and location of an obstacle in a primary path of the mobile machine, determining an alternate path around the obstacle, and delivering a signal to a fleet manager with the location of the obstacle and the alternate path. The apparatus includes an obstacle detection system, a position determining system, a path planner, a communications system, and a control system to receive signals from the obstacle detection system, wherein the positions determining system, the path planner, and the communications system deliver a signal to the fleet manager with the location of the obstacle and the alternate path.
Although the method and the apparatus of the '926 patent may provide detection and evasion of obstacles under mining conditions, it may have limitations. For example, it may be difficult to accurately detect a location of a moving obstacle, such as electric cables tethered to the rear of an earthmoving machine.
The avoidance system of the present disclosure is directed towards improvements to the existing technology.
One aspect of the present disclosure is directed to an avoidance system configured to track a cable tethered from a mobile earthmoving machine along a worksite during operation. The avoidance system may include a sensor system configured to periodically detect a position of the cable within the worksite and generate a position data set in response thereto. A controller may be associated with the sensor system and configured to determine a cable avoidance region based on the position data set.
Another aspect of the present disclosure is directed to a method for tracking a cable tethered from a mobile earthmoving machine along a worksite during operation. The method may include guiding the cable along the worksite via at least one cable guide and determining a position of the at least one cable guide relative to the worksite. The method may also include periodically detecting a position of the cable within the worksite and generating a position data set in response thereto. The method may also include determining a cable avoidance region based on the position data set.
A diagrammatic illustration of a mobile earthmoving machine 1 operating at a worksite 2 is shown in
An avoidance system 13 may be configured to track locations of cable 8 along worksite 2 during operation of machine 1. Avoidance system 13 may include reference markers, such as at least one cable guide 10. Cable guide 10 may be engaged with the worksite surface 11 and configured to guide cable 8 along a worksite surface 11 during operation of machine 1. In one embodiment shown in
A guide member 15 may be mounted on supporting body 12 and configured to direct cable 8 in a fixed travel path in response to movement by machine 1. Cable 8 may be engaged with guide member 15, wherein the guide member 15 supports and elevates cable 8 a desired distance above surface 11. Supporting body 12 and guide member 15 may elevate cable 8 to a sufficient height so as to allow off-road vehicle 9 to travel between adjacent cable guides 10 and underneath cable 8. Portions of cable 8 behind machine 1 (i.e., between machine 1 and an adjacent cable guide 10) may be draped along worksite surface 11 and provided with slack so as to freely move in accordance with movement of machine 1. In this embodiment, guide member 15 may include at least one pulley 17, wherein cable 8 may be draped along pulley 17. Guide member 15 may be pivotally engaged with supporting body 12 so as to accommodate lateral movement of cable 8. Although one pulley 17 is illustrated in
A positioning system 14 may be associated with cable guide 10. As shown in
In the embodiment shown in
It should be appreciated that a variety of known types of electronic markers and receivers may be capable of transmitting and detecting a signal based on the locations of machine 1 and cable guide 10, and that any conventional type of electronic marker may be employed. For example, positioning system 14 may include a passive transponder configured to radiate an electromagnetic field. An appropriate receiver, such as a conventional transceiver, may be employed to detect and locate the transponder, and thus, the locations of machine 1 and cable guide 10. Additionally, azimuth sensors, scanning lasers, radio triangulation systems, microwave technology, or radar, alone or in combination with GPS technology, may also be employed to determine the locations of machine 1 and cable guide 10. Although the exemplary embodiments of the present disclosure have been described in terms of a positioning system for cable guides, it should also be appreciated that the disclosed positioning system is not restricted to cable guides and may also be associated with other reference markers within worksite 2, such as landmarks, poles, stakes, posts, or the like.
During operation, machine 1 may have the ability to reverse, go forward, rotate 360 degrees, and in general, maneuver freely. As machine 1, in particular car body 3, rotates to alternate loading of material and unloading into vehicle 9, or maneuvers along worksite 2, portions of cable 8 engaged between adjacent cable guides 10 may maintain a fixed, straight lined path along worksite surface 11. Other portions of cable 8 not supported by adjacent cable guides 10, for example, a section of cable 8 running immediately from the rear of machine 1, may change position and location in response to movement by machine 1.
As shown in
Sensor system 16 may include at least one sensor 20 for detecting the movement and subsequent position changes of cable 8, and in the embodiments of
As shown in
As shown in the embodiments of
In the embodiment shown in
Although the exemplary embodiments of the present disclosure have been described in terms of an avoidance system for electric cables for mobile earthmoving machines, it should be appreciated that the disclosed avoidance system is not restricted to electric cables for mobile earthmoving machines but may also be employed to track other conduits tethered from mobile earthmoving machines, such as conduits for delivering drilling mud, fluid, and the like. The disclosed avoidance system may also be employed in other applications that use long runs of cable, rope, or piping that may not be considered permanent infrastructure.
The disclosed avoidance system 13 may have applicability with conduits, such as electric cables 8 for a mobile earthmoving machine 1. For example, and as shown in
During operation of machine 1, avoidance system 13 may track and determine the location of cable 8 by detecting position data of cable guide 10 and cable 8. The controller 25 may determine a cable avoidance region 26 based on the position data of the cable guide 10 and cable 8, and responsively deliver the region data to off-road vehicles 9 and any other worksite equipment within worksite 2.
Position and location data of machine 1, cable guide 10, and any other landmarks within worksite 2 may be determined by positioning system 14 and delivered to controller 25, box 330. Controller 25 may generate a position coordinate map of worksite 2 based upon the position data from positioning system 14, box 340. Controller 25 may accurately locate and define the cable avoidance region 26 relative to the position coordinate map, box 350, and thus the entire worksite 2. The cable avoidance region data may be delivered to worksite equipment, such as off-road vehicle 9, in communication with controller 25, box 360. Thereby, an operator of vehicle 9 may determine a traveling path to avoid cable avoidance region 26, and thus, contact with cables 8.
Position and location data of cable guide 10 may be determined by positioning system 14 and delivered to controller 25, box 440. Controller 25 may process the position data of machine 1 and cable guide 10 and accurately locate and define the cable avoidance region 26 relative to the position of machine 1 and cable guide 10, box 450. The cable avoidance region data may be delivered to worksite equipment, such as off-road vehicle 9, in communication with controller 25, box 460. Thereby, an operator of vehicle 9 may determine a traveling path to avoid cable avoidance region 26, and thus, contact with cables 8.
Employing avoidance system 13 within worksite 2 may provide an accurate method to locate constantly moving obstacles, such as cable 8 of a mobile earthmoving machine 1. As cable 8 moves along worksite 2, avoidance system 13 may periodically scan the various positions 22 of cable 8 and develop a cable avoidance region 26 based on a historical compilation of cable 8 positions. Therefore, operators of worksite equipment may plan a traveling path to avoid the cable avoidance region 26, and thus, cable 8. Furthermore, because avoidance system 13 may periodically detect and compile the historical positions of cable 8 to develop the cable avoidance region 26, less bandwidth may be consumed by avoidance system 13 as compared to determining the cable avoidance region 26 based on constantly streaming position data of cable 8.
It will be apparent to those skilled in the art that various modifications and variations can be made to the avoidance system of the present disclosure without departing from the scope of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims.
