Load estimator for scraper

Abstract

A load estimator is disclosed for use with a scraper. The load estimator may have a first sensor configured to generate a first signal indicative of a performance parameter of the scraper, a second sensor configured to generate a second signal indicative of a hydraulic pressure associated with a bowl of the scraper, and a controller in communication with the first and second sensors. The controller may be configured to classify a current segment of an ongoing work cycle based on the first signal. The controller may also be configured to selectively estimate a load of material contained with the bowl of the scraper based on the second signal only when the current segment is classified as a segment where the load can be reliably estimated.

What is claimed is: 
     
         1 . A load estimator for a scraper, comprising:
 a first sensor configured to generate a first signal indicative of a performance parameter of the scraper;   a second sensor configured to generate a second signal indicative of a hydraulic pressure associated with a bowl of the scraper; and   a controller in communication with the first and second sensors, the controller being configured to:
 classify a current segment of an ongoing work cycle based on the first signal; and 
 selectively estimate a load of material contained with the bowl of the scraper based on the second signal only when the current segment is classified as a segment where the load can be reliably estimated. 
   
     
     
         2 . The load estimator of  claim 1 , wherein the performance parameter is associated with at least one of an ejector condition, a transmission gear, a ground speed or location, a cushion hitch status, an apron cylinder condition, an elevator condition, and a bowl actuator position. 
     
     
         3 . The load estimator of  claim 1 , wherein the second signal is indicative of one or more hydraulic pressures within a cylinder configured to raise and lower the bowl. 
     
     
         4 . The load estimator of  claim 1 , wherein the controller is configured to:
 classify the current segment as one of dig segment, a carry segment, a dump segment, and a return segment; and   selectively estimate the load of material contained with the bowl of the scraper based on the second signal only when the current segment is classified as the carry segment.   
     
     
         5 . The load estimator of  claim 5 , wherein the controller is further configured to selectively implement a load estimation calibration procedure only when the current segment is classified as the return segment. 
     
     
         6 . The load estimator of  claim 1 , wherein the controller is further configured to:
 estimate the load of material multiple times during a single segment of a same excavation cycle; and   generate an average value for the load of material based on the load estimated during the multiple times.   
     
     
         7 . The load estimator of  claim 1 , further including a communication device located onboard the scraper, wherein the controller is further configured to transmit the estimated load offboard the scraper via the communication device. 
     
     
         8 . The load estimator of  claim 7 , wherein the controller is further configured to link an identification of the scraper and an operator identification to the estimated load. 
     
     
         9 . The load estimator of  claim 1 , further including a display located within an operator station of the scraper, wherein the controller is further configured to cause a representation of the estimated load to be shown on the display. 
     
     
         10 . The load estimator of  claim 9 , wherein the controller is further configured to:
 track completion of cycles by the scraper based on the first signal;   tabulate a running total of material moved by the scraper based on the completion of cycles and the load estimated during each cycle; and   cause a representation of the running total to be shown on the display.   
     
     
         11 . A method of estimating a load for a scraper, comprising:
 sensing a performance parameter of the scraper;   sensing a hydraulic pressure associated with a bowl of the scraper;   classifying a current segment of an ongoing work cycle based on the performance parameter; and   selectively estimating a load of material contained within the bowl of the scraper based on the hydraulic pressure only when the current segment is classified as a segment where the load can be reliably estimated.   
     
     
         12 . The method of  claim 11 , wherein sensing a performance parameter includes sensing a performance parameter associated with at least one of an ejector condition, a transmission gear, a ground speed, a cushion hitch status, an apron cylinder condition, an elevator condition, and a bowl actuator position. 
     
     
         13 . The method of  claim 11 , wherein sensing a hydraulic pressure includes sensing one or more hydraulic pressures within a cylinder configured to raise and lower the bowl. 
     
     
         14 . The method of  claim 11 , wherein:
 classifying the current segment of the ongoing work cycle includes classifying the current segment as one of a dig segment, a carry segment, a dump segment, and a return segment; and   selectively estimating the load of material contained within the bowl of the scraper includes selectively estimating the load of material only when the current segment is classified as the carry segment.   
     
     
         15 . The method of  claim 14 , further including selectively implementing a load estimation calibration procedure only when the current segment is classified as the return segment. 
     
     
         16 . The method of  claim 11 , wherein selectively estimating the load of material includes:
 estimating the load of material multiple times during a single segment of a same excavation cycle; and   generating an average value for the load of material based on the load estimated during the multiple times.   
     
     
         17 . The method of  claim 11 , further including:
 linking an identification of the scraper and an operator identification to the estimated load; and   communicating the estimated load offboard the scraper.   
     
     
         18 . The method of  claim 11 , further including displaying a representation of the estimated load within an operator station of the scraper. 
     
     
         19 . The method of  claim 18 , further including:
 tracking completion of cycles by the scraper based on the performance parameter;   tabulating a running total of material moved by the scraper based on the completion of cycles and the load estimated during each cycle; and   displaying a representation of the running total within the operator station.   
     
     
         20 . A scraper, comprising:
 a tractor having a transmission;   a bowl having a blade at a front end;   an ejector located at a back end of the bowl;   an apron connected at a leading end of the bowl;   at least a first sensor associated with at least one of the transmission, the ejector, and the apron, the at least a first sensor configured to generate at least a first signal indicative of a gear ratio of the transmission, a condition of the bowl, a condition of the ejector, and a condition of the apron;   a cylinder configured to raise and lower the blade into a work surface;   a pressure sensor configured to sense a pressure of the cylinder and generate a corresponding second signal; and   a controller in communication with the at least a first sensor and the pressure sensor, the controller being configured to:
 classify a current segment of an ongoing work cycle as one of a dig segment, a carry segment, a dump segment, and a return segment based on the at least a first signal; and 
 selectively estimate a load of material contained with the bowl of the scraper based on the second signal only when the current segment is classified as the carry segment.