Work machine with an adaptive control system and method for grade control

Abstract

An adaptive control system automatically controls an attachment position during a grading operation of a surface. The system comprises a frame, an attachment, first sensor, a second sensor, a laser receiver and a controller. The first sensor generates a first sensor signal indicative of an angle of the frame. The second sensor generates a second sensor signal indicative of an angle of the ground-engaging attachment. The laser receiver receives a laser signal from a laser beacon and generates a height signal based on the laser signal. The height signal is indicative of a position of either the attachment or the frame relative to the laser signal. The controller establishes a target grade based on a desired grade of the surface; identifies a position of the attachment; receives the first sensor signal; the second sensor signal; and the laser signal. The controller generates a first control signal or second control signal based on the inputs.

1 . An adaptive control system for a work machine for automatically controlling an attachment position during a grading operation of a surface, the adaptive control system comprising:
 a frame;   an attachment movably coupled to the frame via a boom assembly;   a first sensor configured to generate a first sensor signal indicative of an angle of the frame relative to the direction of gravity;   a second sensor configured to generate a second sensor signal indicative of an angle of the ground-engaging attachment relative to one of the frame and the direction of gravity;   a laser receiver configured to receive a laser signal from a laser beacon, the laser receiver generating a height signal based on the laser signal, the height signal indicative of a position of one of the attachment and the frame relative to the laser signal; and   a controller having a non-transitory computer readable medium with a program instruction to grade the surface, the program instructions when executed causing a processor of the controller:
 establish a target grade based on a desired grade of the surface; 
 identify a position of the attachment with respect to one of the frame, the surface, and the laser signal; 
 receive the first sensor signal from the first sensor; 
 receive the second sensor signal from the second sensor; 
 receive the laser signal from the laser beacon; 
 generate a first control signal based on the height signal, the first control signal causing one or more actuators coupling the attachment to the work machine to maintain the attachment at a position corresponding to the target grade as the work machine propels; and 
 generate a second control signal based on one of the first sensor signal and the second sensor signal in the absence of the height signal, the second control signal causing one or more actuators coupling the attachment to the work machine to maintain the attachment at a position corresponding to a historical value of a grade profile of the attachment as the work machine propels. 
   
     
     
         2 . The adaptive control system of  claim 1 , wherein the laser receiver comprises of a first receiver and a second receiver, wherein each receiver is located on a first laser mast and a second laser mast, respectively, the laser masts extending upwardly from a location fixed relative to the frame. 
     
     
         3 . The adaptive control system of  claim 2 , wherein the first receiver and the second receiver create a first height signal and a second height signal, respectively, the first height signal and the second height signal enabling the controller to calculate a grade profile of the attachment. 
     
     
         4 . The adaptive control system of  claim 3 , wherein in the absence of one of the first height signal and the second height signal, the controller generates a third control signal based on the first sensor signal, the second sensor signal, and the remaining height signal. 
     
     
         5 . The adaptive control system of  claim 1 , wherein the historical value is derived from a predetermined period of time. 
     
     
         6 . The adaptive control system of  claim 1 , wherein the historical value is derived from one of a predetermined tolerance band and a predetermined number of passes. 
     
     
         7 . The adaptive control system of  claim 1 , wherein the historical value is based on a sampling rate dependent on one of a worksite condition and a job function. 
     
     
         8 . The adaptive control system of  claim 1 , wherein the processor is further configured to create a performance degradation alert signal for the grading operation after a predetermined period of time of the second control signal operating the one or more actuators. 
     
     
         9 . The adaptive control system of  claim 1 , wherein the processor is further configured to suspend an auto control mode of maintaining the attachment for the grading operation after a predetermined time of the second control signal operating the one or more actuators. 
     
     
         10 . The adaptive control system  claim 1 , wherein the height signal automatically controls the height of the laser receiver to correspond to the height of the laser signal as the work machine propels. 
     
     
         11 . The method of automatically controlling a position of an attachment on a work machine during a grading operation of a surface, the attachment movably coupled to the frame via a boom assembly, the method comprising:
 establishing a target grade to establish a desired grade of the surface;   identifying a position of the attachment with respect to one of the frame, the surface, and the laser signal;   receiving a first sensor signal from a first sensor, the first sensor signal indicative of an angle of the frame relative to the direction of gravity;   receiving a second sensor signal from a second sensor, the second sensor signal indicative of an angle of the ground-engaging attachment relative to one the frame and the direction of gravity;   receiving a laser signal from a laser beacon;   generating a height signal based on the laser signal received, the height signal indicative of a position of one of the attachment and the frame relative to the laser signal;   generating a first control signal based on the height signal, first the control signal causing one or more actuators coupling the attachment to the work machine to maintain the attachment at a position corresponding to the target grade as the work machine propels; and   generating a second control signal based on one of the first sensor signal and the second sensor signal in the absence of the height signal, the second control signal causing one or more actuators coupling the attachment to the work machine to maintain the attachment at a position corresponding to historical value of a grade profile as the work machine propels.   
     
     
         12 . The method of  claim 11 , wherein the laser signal is received on a first receiver and a second receiver located on a first laser mast and a second laser mast, respectively, the laser masts extending upwardly from a location fixed relative to the frame. 
     
     
         13 . The method of  claim 12 , wherein the first receiver and the second receiver create a first height signal and a second height signal, respectively, the first height signal and the second height signal enabling the controller to calculate one of a grade profile of the attachment. 
     
     
         14 . The method of  claim 13 , wherein in the absence of absence of one of the first height signal and the second height signal, the method includes generating a third control signal based on the first sensor signal, the second sensor signal, and the remaining height signal. 
     
     
         15 . The method of  claim 11 , wherein the historical value is derived from a predetermined period of time. 
     
     
         16 . The method of  claim 11 , wherein the historical value is derived from one of a predetermined tolerance band and a predetermined number of passes. 
     
     
         17 . The method of  claim 11 , wherein the historical value is based on a sampling rate dependent on one of a worksite condition and a job function. 
     
     
         18 . The method of  claim 11 , wherein the method further comprises creating a performance degradation alert signal for the grading operation after a predetermined period of time of the second control signal operating the one or more actuators. 
     
     
         19 . The method of  claim 11 , wherein the method further comprises suspending auto control mode of maintaining the attachment at a position after a predetermined time of the second control signal operating the one or more actuators. 
     
     
         20 . The method of  claim 11 , wherein the height signal automatically controls the height of the laser receiver to correspond to the height of a laser signal as the work machine propels.