US20260015817A1
SYSTEM INCLUDING WORK MACHINE AND METHOD OF CONTROLLING WORK MACHINE
Publication
Application
Classifications
IPC Classifications
CPC Classifications
Applicants
KOMATSU LTD.
Inventors
Takafumi MATSUYAMA
Abstract
A system that allows increase in amount of loading of loads in a container is provided. A work machine includes a bucket. The system including the work machine includes an information obtaining unit that obtains information on a vessel of a dump truck into which loads carried in the bucket are to be loaded and a controller. The controller determines a loading position which is a position of the bucket relative to the vessel in loading the loads into the vessel, based on dimension information on a dimension in a width direction of the bucket and the information on the vessel.
Figures
Description
TECHNICAL FIELD
[0001]The present disclosure relates to a system including a work machine and a method of controlling a work machine.
BACKGROUND ART
[0002]Japanese Patent Laying-Open No. 2017-43887 (PTL 1) discloses a control system that divides a vessel of a dump truck into a central region, a left region, and a right region and shows loading guidance so as to sequentially load in each region, an object to be loaded.
CITATION LIST
Patent Literature
[0003]PTL 1: Japanese Patent Laying-Open No. 2017-43887
SUMMARY OF INVENTION
Technical Problem
[0004]A work machine loads loads into a container such as a vessel of a dump truck. The vessel of the dump truck often has the entire length longer than a width of a bucket of the work machine. In order to increase an amount of loading of loads in the dump truck, a loading position in a fore/aft direction in the vessel should be managed for loading.
[0005]The present disclosure proposes a system including a work machine and a method of controlling a work machine that allow increase in amount of loading of loads in a container.
Solution to Problem
[0006]According to one aspect of the present disclosure, a system including a work machine is proposed. The work machine includes a work implement. The system includes an information obtaining unit that obtains information on a container into which loads carried in the work implement are to be loaded and a controller. The controller determines a loading position which is a position of the work implement relative to the container in loading the loads into the container, based on dimension information on a dimension in a width direction of the work implement and the information on the container.
[0007]According to one aspect of the present disclosure, a method of controlling a work machine is proposed. The method includes obtaining dimension information on a dimension in a width direction of a work implement, obtaining information on a container into which loads carried in the work implement are to be loaded, and determining as a loading position, a position to which the work implement is to be moved with respect to the container in loading of the loads into the container, based on the dimension information of the work implement and the information on the container.
[0008]According to one aspect of the present disclosure, a system including a work machine is proposed. The work machine includes a work implement. The system includes an information obtaining unit that obtains information on a container into which loads carried in the work implement are to be loaded and a controller. The controller determines a target position to which the work implement from which the loads are loaded into the container is headed, based on dimension information on a dimension in a width direction of the work implement and dimension information on a dimension in a fore/aft direction of the container.
Advantageous Effects of Invention
[0009]According to the system including the work machine and the method of controlling the work machine in the present disclosure, the amount of loading of loads in the container can be increased.
BRIEF DESCRIPTION OF DRAWINGS
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
DESCRIPTION OF EMBODIMENTS
[0022]An embodiment will be described below with reference to the drawings. The same components and constituent elements in the description below have the same reference characters allotted and their labels and functions are also the same.
[0023]Therefore, detailed description thereof will not be repeated. Extraction of any features from the embodiment and any combination thereof are also originally intended.
<Overall Construction of Wheel Loader 1 >
[0024]In an embodiment, a wheel loader 1 as an exemplary work machine will be described.
[0025]As shown in
[0026]Travel apparatus 4 serves for travel of the vehicular body of wheel loader 1 and includes running wheels 4a and 4b. Wheel loader 1 is a wheeled vehicle provided with running wheels 4a and 4b as rotational bodies for travel, on opposing sides in a lateral direction of the vehicular body. Wheel loader 1 is self-propelled as running wheels 4a and 4b are rotationally driven and can perform desired works with work implement 3. Travel apparatus 4 corresponds to an exemplary travel unit.
[0027]A direction in which wheel loader 1 travels straight is herein referred to as a fore/aft direction of wheel loader 1. In the fore/aft direction of wheel loader 1, a side where work implement 3 is arranged with respect to vehicular body frame 2 is defined as the fore direction and a side opposite to the fore direction is defined as the aft direction. The lateral direction of wheel loader 1 refers to a direction orthogonal to the fore/aft direction when wheel loader 1 on a flat ground is viewed in a plan view. A right side and a left side in the lateral direction when one faces the fore direction are defined as a right direction and a left direction, respectively. An upward/downward direction of wheel loader 1 is a direction orthogonal to the plane defined by the fore/aft direction and the lateral direction. A side where the ground is located and a side where the sky is located in the upward/downward direction are defined as a lower side and an upper side, respectively.
[0028]Vehicular body frame 2 includes a front frame 2a and a rear frame 2b. Front frame 2a is arranged in front of rear frame 2b. Front frame 2a and rear frame 2b are attached to each other as being laterally operable.
[0029]A pair of steering cylinders 11 is attached across front frame 2a and rear frame 2b. Steering cylinder 11 is a hydraulic cylinder. As steering cylinder 11 extends and contracts with hydraulic oil from a steering pump, a direction of travel of wheel loader 1 laterally changes. Vehicular body frame 2 in an articulated structure is composed of front frame 2a and rear frame 2b. Wheel loader 1 is an articulated work machine in which front frame 2a and rear frame 2b are coupled to allow a flection operation.
[0030]Work implement 3 and a pair of running wheels (front wheels) 4a are attached to front frame 2a. Work implement 3 is attached in front of the main body of wheel loader 1. Work implement 3 is supported by the vehicular body of wheel loader 1. Work implement 3 includes a boom 14 and a bucket 6. Bucket 6 is arranged at a tip end of work implement 3. Bucket 6 is a work tool for excavation and loading. A cutting edge 6a is a tip end portion of bucket 6. A rear surface 6b is a part of an outer surface of bucket 6. Rear surface 6b is formed from a plane. Rear surface 6b extends rearward from cutting edge 6a.
[0031]Boom 14 has a base end portion rotatably attached to front frame 2a by a boom pin 9. Bucket 6 is rotatably attached to boom 14 by a bucket pin 17 located at a tip end of boom 14. Boom pin 9 and bucket pin 17 correspond to a plurality of articulations of work implement 3.
[0032]Work implement 3 further includes a bell crank 18 and a link 15. Bell crank 18 is rotatably supported on boom 14 by a support pin 18a located substantially in a center of boom 14. Link 15 is coupled to a coupling pin 18c provided at a tip end portion of bell crank 18. Link 15 couples bell crank 18 and bucket 6 to each other.
[0033]Front frame 2a and boom 14 are coupled to each other by a pair of boom cylinders 16. Boom cylinder 16 is a hydraulic cylinder. Boom cylinder 16 rotationally drives boom 14 upward and downward around boom pin 9. Boom cylinder 16 has a base end attached to front frame 2a. Boom cylinder 16 has a tip end attached to boom 14. Boom cylinder 16 is a hydraulic actuator that operates boom 14 upward and downward with respect to front frame 2a. With movement upward and downward of boom 14, bucket 6 attached at the tip end of boom 14 also moves upward and downward.
[0034]A bucket cylinder 19 couples bell crank 18 and front frame 2a to each other. Bucket cylinder 19 has a base end attached to front frame 2a. Bucket cylinder 19 has a tip end attached to a coupling pin 18b provided at a base end portion of bell crank 18. Bucket cylinder 19 is a hydraulic actuator to cause bucket 6 to pivot upward and downward with respect to boom 14. Bucket cylinder 19 is a work tool cylinder that drives bucket 6. Bucket cylinder 19 rotationally drives bucket 6 around bucket pin 17. Bucket 6 is constructed as being operable with respect to boom 14. Bucket 6 is constructed as being operable with respect to front frame 2a.
[0035]Boom cylinder 16 and bucket cylinder 19 correspond to an exemplary work implement actuator that drives work implement 3. Travel apparatus 4 as well as boom cylinder 16 and bucket cylinder 19 correspond to an exemplary “movement operation portion” that moves work implement 3.
[0036]Cab 5 on which an operator rides and a pair of running wheels (rear wheels) 4b are attached to rear frame 2b. Cab 5 in a box shape is arranged in the rear of boom 14. Cab 5 is carried on vehicular body frame 2. In cab 5, a seat where the operator of wheel loader 1 is seated, an operation apparatus 8 which will be described later, and the like are arranged.
[0037]Cab 5 is provided with a perception device 111. Perception device 111 is arranged, for example, in a ceiling portion of cab 5. Perception device 111 is mounted, for example, on an upper surface of cab 5. Perception device 111 is arranged, for example, in a front portion of cab 5. Perception device 111 is attached to cab 5, for example, as facing forward, and it can obtain information on the front of cab 5. Details of perception device 111 will be described later.
<System Configuration>
[0038]
[0039]An engine 21 is a drive source that generates drive force to drive work implement 3 and travel apparatus 4, and it is, for example, a diesel engine. A motor driven by a power storage, instead of engine 21, may be employed as the drive source, or both of the engine and the motor may be employed. Output from engine 21 is controlled by adjustment of an amount of fuel to be injected into a cylinder of engine 21.
[0040]Drive force generated by engine 21 is transmitted to a transmission 23. Transmission 23 converts drive force into appropriate torque and a rotation speed. An axle 25 is connected to an output shaft of transmission 23. Drive force converted by transmission 23 is transmitted to axle 25. Drive force is transmitted from axle 25 to running wheels 4a and 4b (
[0041]Some of drive force from engine 21 is transmitted to a work implement pump 13. Work implement pump 13 is a hydraulic pump driven by engine 21 to activate work implement 3 with hydraulic oil it delivers. Work implement 3 is driven by hydraulic oil from work implement pump 13. Hydraulic oil delivered by work implement pump 13 is supplied to boom cylinder 16 and bucket cylinder 19 through a main valve 32. As boom cylinder 16 extends and contracts upon receiving supply of hydraulic oil, boom 14 moves upward and downward. As bucket cylinder 19 extends and contracts upon receiving supply of hydraulic oil, bucket 6 pivots upward and downward.
[0042]Wheel loader 1 includes a vehicular body controller 50. Vehicular body controller 50 includes an engine controller 60, a transmission controller 70, and a work implement controller 80.
[0043]Vehicular body controller 50 is generally implemented by reading of various programs by a central processing unit (CPU). Vehicular body controller 50 includes a not-shown memory. The memory functions as a work memory, and various programs for performing functions of wheel loader 1 are stored in the memory.
[0044]Operation apparatus 8 is provided in cab 5. Operation apparatus 8 is operated by an operator. Operation apparatus 8 includes a plurality of types of operation members operated by the operator to operate wheel loader 1. Operation apparatus 8 includes an accelerator pedal 41 and a work implement control lever 42. Operation apparatus 8 may include a steering wheel, a shift lever, and the like which are not shown.
[0045]Accelerator pedal 41 is operated to set the target number of rotations of engine 21. Engine controller 60 controls output from engine 21 based on an amount of operation onto accelerator pedal 41. With increase in amount of operation (amount of pressing) onto accelerator pedal 41, output from engine 21 increases. With decrease in amount of operation onto accelerator pedal 41, output from engine 21 decreases. Transmission controller 70 controls transmission 23 based on the amount of operation onto accelerator pedal 41.
[0046]Work implement control lever 42 is operated to operate work implement 3. Work implement controller 80 controls electromagnetic proportional control valves 35 and 36 based on the amount of operation onto work implement control lever 42.
[0047]Electromagnetic proportional control valve 35 switches main valve 32 such that bucket cylinder 19 contracts to move bucket 6 in a dump direction (a direction in which the cutting edge of bucket 6 is lowered). Electromagnetic proportional control valve 35 switches main valve 32 such that bucket cylinder 19 extends to move bucket 6 in a tilt direction (a direction in which the cutting edge of bucket 6 is raised). Electromagnetic proportional control valve 36 switches main valve 32 such that boom cylinder 16 contracts to lower boom 14. Electromagnetic proportional control valve 36 switches main valve 32 such that boom cylinder 16 extends to raise boom 14.
[0048]A machine monitor 51 shows various types of information upon receiving input of a command signal from vehicular body controller 50. The various types of information shown on machine monitor 51 may be, for example, information on works performed by wheel loader 1, vehicular body information such as an amount of remaining fuel, a temperature of coolant, and a temperature of hydraulic oil, an image of surroundings obtained by image pick-up of the surroundings of wheel loader 1, and the like. Machine monitor 51 may be implemented by a touch panel, and in this case, a signal generated by touching by the operator onto a part of machine monitor 51 is outputted from machine monitor 51 to vehicular body controller 50.
<Excavation and Loading Works>
[0049]Wheel loader 1 in the present embodiment performs excavation and loading works to scoop an excavation target such as soil and to load the excavation target onto a loading target such as a dump truck.
[0050]
[0051]
[0052]
[0053]
[0054]rearward travel. While bucket 6 is empty as a result of full ejection of excavation target 310 in bucket 6 into vessel 301 of dump truck 300, wheel loader 1 travels rearward along loading path R2 to the position where it started forward travel in
[0055]Wheel loader I can thus repeatedly perform a series of works including excavation, rearward travel, dump approach, soil ejection, and rearward travel.
<Automatic Control System that Controls Wheel Loader 1>
[0056]In automating a loading work for loading onto dump truck 300 by wheel loader 1, in order to more quickly perform the loading work while an amount of works is ensured without contact of bucket 6 with vessel 301, reproduction of operations of work implement 3 by a skilled operator under automatic control has been desired.
[0057]An automation controller 100 is configured to transmit and receive a signal to
[0058]and from vehicular body controller 50 described with reference to
[0059]Perception device 111 obtains information on surroundings of wheel loader 1. Perception device 111 is attached, for example, to a front portion of the upper surface of cab 5. Perception device 111 corresponds to an exemplary object sensor that detects an object around the main body of wheel loader 1.
[0060]Perception device 111 contactlessly detects a direction of an object outside wheel loader 1 and a distance to the object. Perception device 111 is implemented, for example, by light detection and ranging (LiDAR) that obtains information on an object by emission of laser beams. Perception device 111 may be implemented by a visual sensor including a camera. Perception device 111 may be implemented by radio detection and ranging (Radar) that obtains information on an object by emission of radio waves. Perception device 111 may be implemented by an infrared sensor.
[0061]Positional information obtaining device 112 obtains information on a current position of wheel loader 1. Positional information obtaining device 112 obtains, for example, positional information of wheel loader 1 in a global coordinate system with the Earth being defined as a reference, with the use of a satellite positioning system. Positional information obtaining device 112 uses, for example, global navigation satellite systems (GNSS) and includes a GNSS receiver. The satellite positioning system calculates a position of wheel loader 1 by computing a position of an antenna of the GNSS receiver based on a positioning signal received from a satellite by the GNSS receiver.
[0062]External information on the outside of wheel loader 1 obtained by perception device 111 and positional information of wheel loader 1 obtained by positional information obtaining device 112 are inputted to automation controller 100.
[0063]Vehicular body controller 50 is configured to transmit and receive a signal to and from a vehicle information obtaining unit 120, and receives input of information on wheel loader 1 obtained by vehicle information obtaining unit 120. Vehicle information obtaining unit 120 is composed of various sensors mounted on wheel loader 1. Vehicle information obtaining unit 120 includes an articulation angle sensor 121, a vehicle speed sensor 122, a boom angle sensor 123, a bucket angle sensor 124, and a boom cylinder pressure sensor 125.
[0064]Articulation angle sensor 121 detects an articulation angle which is an angle formed between front frame 2a and rear frame 2b, and generates a signal indicating the detected articulation angle. Articulation angle sensor 121 outputs a signal indicating the articulation angle to vehicular body controller 50.
[0065]Vehicle speed sensor 122 detects a speed of movement of wheel loader 1 by travel apparatus 4, for example, by detection of a rotation speed of an output shaft of transmission 23 and generates a signal indicating the detected vehicle speed. Vehicle speed sensor 122 outputs the signal indicating the vehicle speed to vehicular body controller 50. Vehicle speed sensor 122 corresponds to an exemplary travel sensor that detects a status of travel of travel apparatus 4 (travel unit).
[0066]Boom angle sensor 123 is implemented, for example, by a rotary encoder provided in boom pin 9 which is a portion of attachment of boom 14 to vehicular body frame 2. Boom angle sensor 123 detects an angle of boom 14 with respect to a horizontal direction and generates a signal indicating the detected angle of boom 14. Boom angle sensor 123 outputs the signal indicating the angle of boom 14 to vehicular body controller 50.
[0067]Bucket angle sensor 124 is implemented, for example, by a rotary encoder provided in support pin 18a which is a rotation shaft of bell crank 18. Bucket angle sensor 124 detects an angle of bucket 6 with respect to boom 14 and generates a signal indicating the detected angle of bucket 6. Bucket angle sensor 124 outputs the signal indicating the angle of bucket 6 to vehicular body controller 50.
[0068]Boom angle sensor 123 and bucket angle sensor 124 correspond to an exemplary work implement posture sensor that detects a posture of work implement 3.
[0069]Boom cylinder pressure sensor 125 detects a pressure on a bottom side (boom bottom pressure) of boom cylinder 16 and generates a signal indicating the detected boom bottom pressure. The boom bottom pressure becomes higher while bucket 6 is loaded and becomes lower while the bucket is unloaded. Boom cylinder pressure sensor 125 outputs a signal indicating the boom bottom pressure to vehicular body controller 50.
[0070]Vehicular body controller 50 outputs information inputted from vehicle information obtaining unit 120 to automation controller 100. Automation controller 100 receives detection values from vehicle speed sensor 122, boom angle sensor 123, and bucket angle sensor 124 through vehicular body controller 50.
[0071]An actuator 140 is configured to transmit and receive a signal to and from vehicular body controller 50. Upon receiving a command signal from vehicular body controller 50, actuator 140 is driven. Actuator 140 includes a brake EPC (electromagnetic proportional control valve) 141 for activation of a brake of travel apparatus 4, a steering EPC 142 for adjustment of a travel direction of wheel loader 1, a work implement EPC 143 for operations of work implement 3, and a hydraulic mechanical transmission (HMT) 144.
[0072]Electromagnetic proportional control valves 35 and 36 shown in
[0073]Transmission controller 70 includes a brake control unit 71 and an accelerator control unit 72. Brake control unit 71 outputs a command signal for control of activation of the brake to brake EPC 141. Accelerator control unit 72 outputs a command signal for control of the vehicle speed to HMT 144.
[0074]Work implement controller 80 includes a steering control unit 81 and a work implement control unit 82. Steering control unit 81 outputs a command signal for control of the travel direction of wheel loader 1 to steering EPC 142. Work implement control unit 82 outputs a command signal for control of operations of work implement 3 to work implement EPC 143.
[0075]Automation controller 100 includes a position estimator 101, a path planning unit 102, and a path tracking control unit 103.
[0076]Position estimator 101 estimates an own position of wheel loader 1 based on the positional information obtained by positional information obtaining device 112. Position estimator 101 recognizes a target position based on the external information obtained by perception device 111. The target position is, for example, a position of excavation target 310 or dump truck 300 shown in
[0077]Path planning unit 102 generates an optimal path of wheel loader 1 in automatic control of wheel loader 1. The optimal path includes a path for travel by travel apparatus 4 and a path for operations of work implement 3. For example, path planning unit 102 generates an optimal path of wheel loader 1 that performs loaded forward travel toward dump truck 300 and an optimal path of wheel loader 1 that moves away from dump truck 300 in unloaded rearward travel, in the loading work for loading onto dump truck 300. Path planning unit 102 generates an optimal path that connects a current own position of wheel loader 1 to a target position to which wheel loader 1 is headed from now, while the loading work for loading onto dump truck 300 is performed.
[0078]Path tracking control unit 103 controls the accelerator, the brake, and steering such that wheel loader 1 travels as following the optimal path generated by path planning unit 102. Path tracking control unit 103 outputs a command signal for travel of wheel loader 1 along the optimal path to brake control unit 71, accelerator control unit 72, and steering control unit 81. Path tracking control unit 103 controls boom cylinder 16 and bucket cylinder 19 such that work implement 3 operates along the optimal path generated by path planning unit 102. Path tracking control unit 103 outputs a command signal for movement of work implement 3 along the optimal path to work implement control unit 82.
[0079]An interface 130 is configured to transmit and receive a signal to and from vehicular body controller 50. Interface 130 includes an automation switch 131, an engine emergency stop switch 132, and a mode indicator 133.
[0080]Automation switch 131 is operated by the operator. The operator operates automation switch 131 to switch between a manual operation of wheel loader 1 and automatic control of wheel loader 1. Engine emergency stop switch 132 is operated by the operator. When an event that requires emergency stop of engine 21 occurs, the operator operates engine emergency stop switch 132. A signal resulting from an operation onto automation switch 131 and engine emergency stop switch 132 is inputted to vehicular body controller 50.
[0081]Mode indicator 133 indicates whether wheel loader 1 is currently in a mode of the manual operation by the operator or an automatic control mode. Vehicular body controller 50 outputs a command signal for control of turn-on of the indicator to mode indicator 133.
<Vessel 301 >
[0082]
[0083]In
[0084]Vessel 301 is provided in a rear portion of dump truck 300. A cab is provided in a front portion of dump truck 300, and vessel 301 is arranged in the rear of the cab. Vessel 301 is structured such that an object to be loaded which has a weight, such as soil and crushed stone, can be carried therein.
[0085]As shown in
[0086]Front wall surface 303 is in a flat shape. Front wall surface 303 extends forward and upward from a front end of bottom surface 302. Front wall surface 303 extends as being inclined forward, toward the upward direction. Front wall surface 303 forms a front wall surface of vessel 301. The front wall surface of vessel 301 is inclined upward, toward the front. Front wall surface 303 is provided with a front upper edge 304. Front upper edge 304 extends in the lateral direction. Front upper edge 304 forms a front edge portion of vessel 301.
[0087]Rear inclined surface 305 is in a flat shape. Rear inclined surface 305 extends rearward and upward from a rear end of bottom surface 302. Rear inclined surface 305 extends as being inclined rearward, toward the upward direction. Rear inclined surface 305 is inclined upward, toward the rear. Rear inclined surface 305 is provided with a rear upper edge 306. Rear upper edge 306 extends in the lateral direction. Rear upper edge 306 forms a rear edge portion of vessel 301. Rear upper edge 306 is located at a position lower than front upper edge 304.
[0088]
<Flow of Automatic Loading on Dump>
[0089]
[0090]In step S1, the number of times of loading indicating how many times wheel loader 1 should perform works for loading loads into vessel 301 of one dump truck 300 to achieve a condition of full load in vessel 301 is calculated.
[0091]For example, the shape of dump truck 300 is obtained by LiDAR which is perception device 111. Point group data indicating three-dimensional coordinate values of measurement points on dump truck 300 is obtained by irradiating dump truck 300 with laser beams from LiDAR. Dump truck 300 is sensed from four directions of the fore direction, the aft direction, the right direction, and the left direction, and the shape of vessel 301 can be recognized based on information on a point group. The recognized shape of vessel 301 is inputted to automation controller 100. Automation controller 100 calculates a maximum loading capacity of vessel 301 and calculates a dimension of vessel 301, based on the shape of vessel 301. Perception device 111 corresponds to an exemplary “information obtaining unit” that obtains information on vessel 301.
[0092]Wheel loader 1 and dump truck 300 may establish inter-vehicle communication with each other. Wheel loader 1 may include a communication unit that communicates with dump truck 300 in addition to the system configuration shown in
[0093]Information on bucket 6 is stored in vehicular body controller 50. The information on bucket 6 includes a dimension of bucket 6 and a capacity of bucket 6. The dimension of bucket 6 includes a dimension in a width direction of bucket 6. The width direction of bucket 6 refers to a direction in parallel to a direction of extension of bucket pin 17 that couples bucket 6 and boom 14 to each other and a direction perpendicular to the sheet plane in
[0094]In wheel loader 1, bucket 6 is replaceable. Vehicular body controller 50 outputs the information on bucket 6 currently attached to the tip end of work implement 3 to automation controller 100.
[0095]A density of excavation target 310 excavated by wheel loader 1 and loaded into vessel 301 of dump truck 300 is also inputted to automation controller 100. The density of excavation target 310 may be estimated by automation controller 100 based on a result of detection of excavation target 310 by perception device 111 which is a visual sensor such as a camera. The density of excavation target 310 may be inputted by the operator through interface 130.
[0096]The automation controller determines the number of times of loading based on the maximum loading capacity of vessel 301, the capacity of bucket 6, and the density of excavation target 310. When vessel 301 has the maximum loading capacity up to which excavation target 310 (loads) carried in bucket 6 can be loaded a plurality of times, the number of times of loading is set to the plurality of times. Though an example in which the number of times of loading is set to four times will be described below, the number of times of loading is naturally not limited to four times.
[0097]In step S2, automation controller 100 determines as the loading position, a position to which work implement 3 (bucket 6) is to be moved with respect to vessel 301 in loading of loads carried in work implement 3 (bucket 6) into vessel 301. The loading position is a position of work implement 3 (bucket 6) relative to vessel 301 in loading the loads carried in work implement 3 (bucket 6) into vessel 301.
[0098]
[0099]
[0100]Wheel loader 1 travels forward from the lateral side (left) of dump truck 300 toward vessel 301 and performs the loading work. The width direction of bucket 6 during the loading work coincides with the fore/aft direction (in
[0101]Bucket 6 shown in
[0102]
[0103]
[0104]Automation controller 100 determines a position where there is no interference by work implement 3 (bucket 6) in loading of loads in vessel 301, as loading position A, loading position B, and loading position D. Loading position A, loading position B, and loading position D are set as positions where a left end of bucket 6 is distant by a prescribed distance from front wall surface 303 of vessel 301 when bucket 6 in the full dump posture is viewed from the rear of wheel loader 1 (viewed when one faces front).
[0105]A position of the left end of bucket 6 relative to central point 6aC of cutting edge 6a is calculated based on the dimension in the width direction of bucket 6. While bucket 6 is located at loading position A, loading position B, and loading position D, the left end of bucket 6 is distant rearward by a prescribed distance from front wall surface 303 in the fore/aft direction of dump truck 300. While bucket 6 is located at loading position A, loading position B, and loading position D, there is a clearance in the fore/aft direction of dump truck 300 between the left end of bucket 6 and front wall surface 303 of dump truck 300.
[0106]Automation controller 100 determines as loading position C, a position where the loads loaded in vessel 301 do not fall from vessel 301. Loading position C is set as a position where a right end of bucket 6 is distant by a prescribed distance from rear upper edge 306 of vessel 301 when bucket 6 in the full dump posture is viewed from the rear of wheel loader 1 (viewed when one faces front). A position of the right end of bucket 6 relative to central point 6aC of cutting edge 6a is calculated based on the dimension in the width direction of bucket 6. While bucket 6 is located at loading position C, the right end of bucket 6 is distant forward by a prescribed distance from rear upper edge 306 in the fore/aft direction of dump truck 300.
[0107]A height of cutting edge 6a of bucket 6 at each of loading position A, loading position B, loading position C, and loading position D is determined based on the capacity of bucket 6, the capacity of vessel 301, the number of times of loading (four times), and a height of the loads in vessel 301 estimated from records of the loading positions. The records of the loading positions indicate records about how many times loading was performed before present loading and in which order loads were loaded to which position until previous loading. A shape of the load in vessel 301 is estimated from the records of the loading positions. The shape of the load in vessel 301 can also be defined as a fill factor of loads in vessel 301. As loading into vessel 301 is continued, the height of the loads in vessel 301 changes. The height of cutting edge 6a in present loading is determined in accordance with the height of the loads loaded in vessel 301 until previous loading.
[0108]As shown in
[0109]Front wall surface 303 of vessel 301 is inclined with respect to the fore/aft direction and the lateral direction of dump truck 300. Front wall surface 303 is inclined obliquely forward and upward, so as to be located forward toward the upward direction. The loading position is determined in conformity with an inclination of front wall surface 303 of vessel 301. As shown in
[0110]Front upper edge 304 and rear upper edge 306 of vessel 301 are not equal to each other in height position, and front upper edge 304 is located at a position higher than rear upper edge 306. More loads are loaded on a front side of vessel 301. As shown in
[0111]Loading position C is set to a position where loads at an angle of repose do not fall from vessel 301 in loading of loads into vessel 301. For example, the loading position is determined in such a manner that, in view of an angle of repose of sand which is 30°, the angle of loads formed with respect to the fore/aft direction of dump truck 300 at rear upper edge 306 is not larger than 30°.
[0112]Referring back to
[0113]Alternatively, perception device 111 may be used to obtain the direction and the distance of vessel 301 of dump truck 300 from a position of arrangement of perception device 111, to thereby calculate the current position of cutting edge 6a of bucket 6 relative to vessel 301.
[0114]Automation controller 100 recognizes a target position. For example, in the loading work by four-time loading shown in
[0115]Automation controller 100 generates an optimal path that connects the current own position of bucket 6 to the target position to which bucket 6 from which loads are loaded into vessel 301 is headed from now. As described above, the optimal path includes the path for travel by travel apparatus 4 and the path for operations of work implement 3.
[0116]Then in step S4, automation controller 100 has wheel loader 1 travel along the optimal path and has work implement 3 operate to perform loading to a designated portion of vessel 301. Automation controller 100 outputs a command for travel of travel apparatus 4 along the optimal path to brake control unit 71, accelerator control unit 72, and steering control unit 81 of vehicular body controller 50. Upon receiving a command signal, travel apparatus 4 operates. Automation controller 100 outputs a command to extend and contract boom cylinder 16 and bucket cylinder 19 to work implement control unit 82 of work implement controller 80. Upon receiving a command signal, boom cylinder 16 and bucket cylinder 19 operate.
[0117]In step S5, automation controller 100 determines whether or not the number of times of loading has reached a defined number. Since the number of times of loading has been set to four times, at time points of ends of the first, second, and third loadings, the number of times of loading has not reached the defined number. When the number of times of loading is determined as not having reached the defined number (NO in step S5), the process returns to step S3. The optimal path to a next target position is generated and loading of the loads into vessel 301 is repeated.
[0118]When the fourth loading ends and the number of times of loading is determined as having reached the defined number (YES in step S5), the process ends (“end” in
<Another Example of Loading Work>
[0119]
[0120]In the loading work shown in
[0121]
[0122]In the loading work shown in
<Functions and Effects>
[0123]Characteristic features and functions and effects of the present embodiment will be summarized as below, although some description may overlap with the description above.
[0124]As shown in
[0125]When wheel loader 1 performs loading into vessel 301 with the entire length longer than the width of its own bucket 6, by appropriate management of the loading position in the fore/aft direction of vessel 301, contact of bucket 6 with vessel 301 or fall of loads from vessel 301 during loading can be suppressed. Therefore, the amount of loading of loads in vessel 301 can be increased.
[0126]As shown in
[0127]As shown in
[0128]As shown in
[0129]As shown in
[0130]As shown in
[0131]As shown in
[0132]As shown in
[0133]As shown in
[0134]Automation controller 100 included in the automatic control system for wheel loader 1 described in the embodiment above does not necessarily have to be mounted on wheel loader 1. Such a system that a controller outside wheel loader 1 implements automation controller 100 may be configured. An external controller may determine loading positions A to D which are positions of bucket 6 relative to vessel 301, based on the dimension information on the dimension in the width direction of bucket 6 and the information on vessel 301.
[0135]The external controller may be arranged at a worksite of wheel loader 1 or at a remote location distant from the worksite of wheel loader 1. The external controller may be a transportable device. The external controller may be a portable device that can be used as being carried by a worker, such as a notebook personal computer, a tablet computer, or a smartphone.
[0136]In the embodiment, an example in which wheel loader 1 is a manned vehicle including cab 5 on which the operator rides is described. Wheel loader 1 may be an unmanned vehicle. Wheel loader 1 does not have to include cab 5 on which the operator rides for performing operations. Wheel loader 1 does not have to be equipped with a function for manipulating by the operator who rides on the cab. Wheel loader 1 may be a work machine dedicated for remote control. Wheel loader 1 may be manipulated through a wireless signal from a remote control device.
[0137]In the embodiment, exemplary machine control in which automation controller 100 automates the loading work onto dump truck 300 by wheel loader 1 is described. A machine guidance function to show a loading position determined by the controller on a display in front of the driver's seat where the operator who controls wheel loader 1 sits to have the operator perform the loading work in accordance with the loading position may be performed.
[0138]In the embodiment, though wheel loader 1 is exemplified as an exemplary work machine, other types of loading machines are also applicable. The loading machine may be a track loader. The loading machine may be an excavator. The excavator may be a hydraulic excavator, a mechanical rope excavator, or a hybrid excavator. The excavator may be a backhoe or a loading excavator. The loading machine may be a bucket crane. In an example where the loading machine includes a work implement, a revolving unit that supports the work implement, and a revolution operation portion that revolves the revolving unit, the revolution operation portion is encompassed in the “movement operation portion.” The revolution operation portion is, for example, a revolution motor. The revolution motor may be a hydraulic motor or an electric motor.
<Additional Aspects>
[0139]The description above includes features additionally described below.
(Additional Aspect 1)
- [0141]an information obtaining unit that obtains information on a container into which loads carried in the work implement are to be loaded, and
- [0142]a controller that determines a loading position which is a position of the work implement relative to the container in loading the loads into the container, based on dimension information on a dimension in a width direction of the work implement and the information on the container.
(Additional Aspect 2)
- [0144]the controller is provided in the work machine.
(Additional Aspect 3)
- [0146]the container has a maximum loading capacity up to which the loads can be loaded a plurality of times, and the controller determines the loading position in each loading.
(Additional Aspect 4)
- [0148]the controller sets as the loading position in first loading, a position where an end of the work implement in the width direction is distant rearward by a prescribed distance from a front wall surface of the container.
(Additional Aspect 5)
- [0150]the controller determines the prescribed distance as a distance for prevention of the work implement from interfering with the container in loading of the loads into the container.
(Additional Aspect 6)
- [0152]the controller sets as the loading position in first loading, a position where an end of the work implement in the width direction is distant forward by a prescribed distance from a rear edge of the container.
(Additional Aspect 7)
- [0154]the controller determines the prescribed distance as a distance sufficient for the loads loaded in the container not to fall from the container.
(Additional Aspect 8)
- [0156]the rear edge of the container is located at a position lower than a front edge of the container.
(Additional Aspect 9)
- [0158]the work implement includes a bucket at a tip end, and
- [0159]the controller determines a position relative to the container, of a tip end of the bucket while the bucket is in a full dump posture.
(Additional Aspect 10)
[0160]The system according to any one of Additional Aspects 1 to 9 further includes a movement operation portion that moves the work implement relatively to the container.
[0161]It should be understood that the embodiment disclosed herein is illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims rather than the description above and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
REFERENCE SIGNS LIST
[0162]1 wheel loader; 2 vehicular body frame; 2a front frame; 2b rear frame; 3 work implement; 4 travel apparatus; 4a, 4b running wheel; 5 cab; 6 bucket; 6a cutting edge; 6aC central point; 8 operation apparatus; 9 boom pin; 11 steering cylinder; 13 work implement pump; 14 boom; 15 link; 16 boom cylinder; 17 bucket pin; 18 bell crank; 18a support pin; 18b, 18c coupling pin; 19 bucket cylinder; 21 engine; 23 transmission; 25 axle; 32 main valve; 35, 36 electromagnetic proportional control valve; 41 accelerator pedal; 42 work implement control lever; 50 vehicular body controller; 51 machine monitor; 60 engine controller; 70 transmission controller; 71 brake control unit; 72 accelerator control unit; 80 work implement controller; 81 steering control unit; 82 work implement control unit; 100 automation controller; 101 position estimator; 102 path planning unit; 103 path tracking control unit; 110 external information obtaining unit; 111 perception device; 112 positional information obtaining device; 120 vehicle information obtaining unit; 121 articulation angle sensor; 122 vehicle speed sensor; 123 boom angle sensor; 124 bucket angle sensor, 125 boom cylinder pressure sensor; 130 interface; 131 automation switch; 132 engine emergency stop switch; 133 mode indicator; 140 actuator; 141 brake EPC; 142 steering EPC; 143 work implement EPC; 144 HMT; 300 dump truck; 301 vessel; 302 bottom surface; 303 front wall surface; 304 front upper edge; 305 rear inclined surface; 306 rear upper edge.
Claims
1. A system including a work machine, the work machine including a work implement, the system comprising:
an information obtaining unit that obtains information on a container into which loads carried in the work implement are to be loaded; and
a controller that determines a loading position which is a position of the work implement relative to the container in loading the loads into the container, based on dimension information on a dimension in a width direction of the work implement and the information on the container.
2. The system according to
the controller is provided in the work machine.
3. The system according to
the container has a maximum loading capacity up to which the loads can be loaded a plurality of times, and
the controller determines the loading position in each loading.
4. The system according to
the controller sets as the loading position in first loading, a position where an end of the work implement in the width direction is distant rearward by a prescribed distance from a front wall surface of the container.
5. The system according to
the controller determines the prescribed distance as a distance for prevention of the work implement from interfering with the container in loading of the loads into the container.
6. The system according to
the controller sets as the loading position in first loading, a position where an end of the work implement in the width direction is distant forward by a prescribed distance from a rear edge of the container.
7. The system according to
the controller determines the prescribed distance as a distance sufficient for the loads loaded in the container not to fall from the container.
8. The system according to
the rear edge of the container is located at a position lower than a front edge of the container.
9. The system according to
the work implement includes a bucket at a tip end, and
the controller determines a position relative to the container, of a tip end of the bucket while the bucket is in a full dump posture.
10. The system according to
11. A method of controlling a work machine, the method comprising:
obtaining dimension information on a dimension in a width direction of a work implement;
obtaining information on a container into which loads carried in the work implement are to be loaded; and
determining as a loading position, a position to which the work implement is to be moved with respect to the container in loading of the loads into the container, based on the dimension information of the work implement and the information on the container.
12. A system including a work machine, the work machine including a work implement, the system comprising:
an information obtaining unit that obtains information on a container into which loads carried in the work implement are to be loaded; and
a controller that determines a target position to which the work implement from which the loads are loaded into the container is headed, based on dimension information on a dimension in a width direction of the work implement and dimension information on a dimension in a fore/aft direction of the container.
13. The system according to
the controller is provided in the work machine.