Blade detection avoidance for an excavator with ultrasonic systems

Abstract

A work machine includes an upper frame rotatably assembled with a lower frame via a rotary joint. A blade is assembled with the lower frame. A controller operably coupled with one of the upper or lower frames, or the blade, wherein the controller includes a memory having instructions stored therein that are executable by a processor to cause the processor to determine a reference frame translation module based on output provided by an angle sensor coupled to the upper frame or the lower frame, wherein the angle sensor is configured to measure a swing angle of the upper frame relative to the lower frame. The processor determines an exclusion zone based on the reference frame translation module and radius range of motion of the blade relative to the lower frame. An object detection system determines whether an object detected is interior or exterior to the exclusion zone.

1 . A method of operating a work machine including an upper frame rotatably assembled with a lower frame via a rotary joint, the work machine including a work implement coupled to the lower frame, the method comprising:
 determining, by a controller of the work machine, a reference frame translation module based on output provided by an angle sensor coupled to at least one of the upper frame and the lower frame, wherein the angle sensor is configured to measure a swing angle of the upper frame relative to the lower frame;   determining, by the controller of the work machine, an exclusion zone based on the reference frame translation module and a radius range of motion of the work implement relative to the lower frame; and   determining, by the controller of the work machine and with the aid of an object detection system, whether an object detected by the object detection system is interior or exterior to the exclusion zone.   
     
     
         2 . The method of  claim 1 , further comprising:
 determining, by the controller of the work machine, a current position of the work implement relative to the lower frame; and   determining, by the controller of the work machine, a dynamic exclusion zone based on the current position of the work implement.   
     
     
         3 . The method of  claim 2 , wherein the work implement is a blade. 
     
     
         4 . The method of  claim 1 , further comprising:
 determining, by the controller of the work machine, a lower measured angle of the upper frame relative to the lower frame based on the swing angle, wherein when the swing angle is greater than 0° then the lower measured angle is equal to the swing angle, and when the swing angle is less than 0° then the lower measured angle is 360° plus the swing angle.   
     
     
         5 . The method of  claim 1 , wherein the determining the exclusion zone includes determining a static arc based on output provided by an implement movement sensor coupled to the work implement, wherein the implement movement sensor is configured to measure a range of motion of the work implement relative to the lower frame. 
     
     
         6 . The method of  claim 1 , wherein the determining the exclusion zone includes determining a static arc based on data for the work implement mounted on the lower frame. 
     
     
         7 . The method of  claim 6 , wherein the static arc is measured relative to a longitudinal axis of the work machine. 
     
     
         8 . The method of  claim 1 , wherein the radius range of motion of the work implement relative to the lower frame includes a maximum radius of movement of the work implement and a minimum radius of movement of the of the work implement. 
     
     
         9 . The method of  claim 1 , wherein the determining the object detected by the object detection system is exterior to the exclusion zone, then sending, via the controller, a warning to an operator of the work machine. 
     
     
         10 . A work machine comprising:
 an upper frame rotatably assembled with a lower frame via a rotary joint, wherein the rotary joint is configured to enable rotation of the upper frame about the lower frame;   a work implement assembled with the lower frame;   a controller operably coupled with one of the upper frame, the lower frame, or the work implement, wherein the controller includes a memory having instructions stored therein that are executable by a processor to cause the processor to:
 determine a reference frame translation module based on output provided by an angle sensor coupled to at least one of the upper frame and the lower frame, wherein the angle sensor is configured to measure a swing angle of the upper frame relative to the lower frame; 
 determine an exclusion zone based on the reference frame translation module and a radius range of motion of the work implement relative to the lower frame; and 
 determine with the aid of an object detection system, whether an object detected by the object detection system is interior or exterior to the exclusion zone. 
   
     
     
         11 . The work machine of  claim 10 , wherein the work machine is an excavator and the work implement is a blade. 
     
     
         12 . The work machine of  claim 10 , further comprising:
 an implement movement sensor coupled to the work implement, wherein the implement movement sensor is configured to measure the radius range of movement of the work implement.   
     
     
         13 . The work machine of  claim 10 , wherein the processor is further configured to:
 determine a current position of the work implement relative to the lower frame; and   determine a dynamic exclusion zone based on the current position of the work implement.   
     
     
         14 . The work machine of  claim 10 , wherein the processor is further configured to:
 determine a lower measured angle of the upper frame relative to the lower frame based on the swing angle, wherein when the swing angle is greater than 0° then the lower measured angle is equal to the swing angle, and when the swing angle is less than 0° then the lower measured angle is 360° plus the swing angle.   
     
     
         15 . The work machine of  claim 10 , wherein the determine the exclusion zone includes determining a static arc based on output provided by an implement movement sensor coupled to the work implement, wherein the implement movement sensor is configured to measure a range of motion of the work implement relative to the lower frame. 
     
     
         16 . The work machine of  claim 10 , wherein the determine the exclusion zone includes determining a static arc based on data for the work implement mounted on the lower frame. 
     
     
         17 . The work machine of  claim 16 , wherein the static arc is measured relative to a longitudinal axis of the work machine. 
     
     
         18 . The work machine of  claim 10 , wherein the radius range of motion of the work implement relative to the lower frame includes a maximum radius of movement of the work implement and a minimum radius of movement of the of the work implement. 
     
     
         19 . The work machine of  claim 10 , wherein the determine the object detected by the object detection system is exterior to the exclusion zone, then send, via the controller, a warning to an operator of the work machine. 
     
     
         20 . The work machine of  claim 10 , further comprising:
 a blade detection avoidance module that is operatively coupled to the controller, wherein the blade detection avoidance module is operable between an engaged condition and a disengaged condition, wherein in the engaged condition, the blade detection avoidance module avoids detection of the work implement, and in the disengaged condition, the blade detection avoidance module does not track the work implement.