Work machine, method, and system for controlling work machine

Abstract

A work machine includes a vehicle body, a traveling wheel supported by the vehicle body, a steering actuator, an articulate actuator, a travelling wheel steering angle sensor, an articulate angle sensor, an object sensor, and a controller. The vehicle body includes a rear frame and a front frame connected to the rear frame so as to be pivotable left and right. The steering actuator steers the traveling wheel to the left and right. The articulate actuator changes an articulate angle between the rear frame and the front frame. The object sensor detects an object in a periphery of the work machine and outputs a signal indicating the presence of the object. The controller sets a detection range in the periphery in accordance with the steering and articulate angles, and determines the presence of the object in the detection range based on the signal from the object sensor.

1 . A work machine comprising:
 a vehicle body including a rear frame and a front frame connected to the rear frame so as to be pivotable left and right;   a traveling wheel supported by the vehicle body;   a steering actuator usable to steer the traveling wheel to the left and right;   an articulate actuator usable to change an articulate angle between the rear frame and the front frame;   a steering angle sensor configured to detect a steering angle of the traveling wheel;   an articulate angle sensor configured to detect the articulate angle;   an object sensor configured to detect an object in a periphery of the work machine and output a signal indicating a presence of the object; and   a controller configured to
 set a detection range in the periphery of the work machine, and 
 determine the presence of the object in the detection range based on the signal from the object sensor, 
   the controller being configured to set the detection range in accordance with the steering angle and the articulate angle.   
     
     
         2 . The work machine according to  claim 1 , wherein
 the controller is configured to
 set a reference range of the detection range based on a width of the vehicle body, and 
 change the detection range from the reference range in accordance with the articulate angle. 
   
     
     
         3 . The work machine according to  claim 2 , wherein
 the controller is configured to curve the detection range in accordance with a turning radius of the work machine corresponding to the articulate angle when the work machine turns in accordance with the articulate angle.   
     
     
         4 . The work machine according to  claim 2 , wherein
 the controller is configured to increase the detection range from the reference range in a left-right direction in accordance with the articulate angle when a direction of the articulate angle and a turning direction of the work machine are opposite.   
     
     
         5 . The work machine according to  claim 4 , wherein
 the controller is configured to increase the detection range from the reference range on a same side as the rear frame with respect to the front frame in the left-right direction when the detection range is set in front of the front frame.   
     
     
         6 . The work machine according to  claim 4 , wherein
 the controller is configured to increase the detection range from the reference range on a same side as the front frame with respect to the rear frame in a left-right direction when the detection range is set behind the rear frame.   
     
     
         7 . The work machine according to  claim 2 , further comprising:
 a leaning actuator configured to change a leaning angle of the traveling wheel; and   a leaning angle sensor configured to detect the leaning angle,   the controller being configured to change the detection range from the reference range in accordance with the leaning angle.   
     
     
         8 . The work machine according to  claim 7 , wherein
 the controller is configured to increase the detection range from the reference range in a same direction that the traveling wheel is leaning in a left-right direction.   
     
     
         9 . The work machine according to  claim 8 , wherein
 the controller is configured not to increase the detection range corresponding to the leaning angle when
 a turning direction of the work machine and a direction of the articulate angle are in opposite directions and 
 a direction that the traveling wheel is leaning matches the turning direction of the work machine. 
   
     
     
         10 . A method for controlling a work machine, the work machine including a vehicle body that includes a rear frame and a front frame that is connected to the rear frame so as to be pivotable left and right, a traveling wheel supported by the vehicle body, a steering actuator for steering the traveling wheel to the left and right, and an articulate actuator for changing an articulate angle between the rear frame and the front frame, the method comprising:
 detecting a steering angle of the traveling wheel;   detecting the articulate angle;   receiving a signal indicating a presence of an object in a periphery of the work machine;   setting a detection range in the periphery of the work machine in accordance with the steering angle and the articulate angle; and   determining the presence of the object in the detection range based on the signal output by an object sensor.   
     
     
         11 . The method according to  claim 10 , further comprising:
 setting a reference range of the detection range based on a width of the vehicle body; and   changing the detection range from the reference range in accordance with the articulate angle.   
     
     
         12 . The method according to  claim 11 , further comprising:
 curving the detection range in accordance with a turning radius of the work machine corresponding to the articulate angle when the work machine turns in accordance with the articulate angle.   
     
     
         13 . The method according to  claim 11 , further comprising:
 increasing the detection range from the reference range in a left-right direction in accordance with the articulate angle when a direction of the articulate angle and a turning direction of the work machine are opposite.   
     
     
         14 . The method according to  claim 13 , further comprising:
 increasing the detection range from the reference range on a same side as the rear frame with respect to the front frame in the left-right direction when the detection range is set in front of the front frame.   
     
     
         15 . The method according to  claim 13 , further comprising:
 increasing the detection range from the reference range on a same side as the front frame with respect to the rear frame in the left-right direction when the detection range is set behind the rear frame.   
     
     
         16 . The method according to  claim 11 , wherein
 the work machine further includes a leaning actuator configured to change a leaning angle of the traveling wheel, and   
       the method further comprises”
 detecting the leaning angle; and 
 changing the detection range from the reference range in accordance with the leaning angle. 
 
     
     
         17 . The method according to  claim 16 , further comprising:
 increasing the detection range from the reference range in a same direction that the traveling wheel is leaning in a left-right direction.   
     
     
         18 . The method according to  claim 17 , further comprising:
 not increasing the detection range corresponding to the leaning angle when
 a turning direction of the work machine and a direction of the articulate angle are in opposite directions and 
 a direction that the traveling wheel is leaning matches the turning direction of the work machine. 
   
     
     
         19 . A system for controlling a work machine, the work machine including a vehicle body that includes a rear frame and a front frame that is connected to the rear frame so as to be pivotable left and right, a traveling wheel supported by the vehicle body, a steering actuator for steering the traveling wheel to the left and right, and an articulate actuator for changing an articulate angle between the rear frame and the front frame, the system comprising:
 a steering angle sensor configured to detect a steering angle of the traveling wheel;   an articulate angle sensor configured to detect the articulate angle;   an object sensor configured to detect an object in a periphery of the work machine, and outputs a signal indicating a presence of the object; and   a controller configured to
 set a detection range in the periphery of the work machine and 
 determine the presence of the object in the detection range based on the signal from the object sensor, 
   the controller being configured to set the detection range in accordance with the steering angle and the articulate angle.