Compaction System and Method for Determining Roller Decoupling

Abstract

A compaction system and a method for determining decoupling of a roller from a work material are disclosed. The compaction system includes a roller configured to compact a work material through rolling engagement with the work material. The compaction system also includes a propulsion device configured to propel the roller along the work material, a power source operatively coupled to the propulsion device, a sensor configured to generate a signal that is indicative of a power potential from the power source, and a controller operatively coupled to the sensor. The controller is configured to receive the signal from the sensor, determine a first variance for a first time duration of the signal, determine a second variance for a second time duration of the signal, and determine the roller is decoupled from the work material based on at least one of the first variance and the second variance.

We claim: 
     
         1 . A compaction system comprising:
 a roller configured to compact a work material through rolling engagement with the work material;   a propulsion device configured to propel the roller along the work material;   a power source operatively coupled to the propulsion device;   a sensor configured to generate a signal that is indicative of a power potential from the power source; and   a controller operatively coupled to the sensor, the controller configured to:
 receive the signal from the sensor; 
 determine a first variance for a first time duration of the signal; 
 determine a second variance for a second time duration of the signal; and 
 determine the roller is decoupled from the work material based on at least one of the first variance and the second variance. 
   
     
     
         2 . The compaction system of  claim 1 , wherein the controller is further configured to:
 compare the first variance and the second variance; and   determine the roller is decoupled from the work material when a difference between the first variance and the second variance exceeds a threshold.   
     
     
         3 . The compaction system of  claim 1 , wherein the controller is further configured to determine the roller is decoupled from the work material when a magnitude of the second variance exceeds a first threshold. 
     
     
         4 . The compaction system of  claim 1 , wherein the controller is further configured to forward an alert to an operator, the alert indicating that the roller is decoupled from the work material. 
     
     
         5 . The compaction system of  claim 1 , wherein the controller is further configured to adjust the power potential of the power source when the roller is decoupled from the work material. 
     
     
         6 . The compaction system of  claim 5 , wherein the controller is further configured to adjust the power potential of the power source based on at least one of the first variance and the second variance when the roller is decoupled from the work material. 
     
     
         7 . The compaction system of  claim 1 , wherein the power source is a hydraulic power source and the signal is a hydraulic pressure signal. 
     
     
         8 . The compaction system of  claim 7 , wherein the sensor is operatively coupled to an axle drive of the propulsion device and the signal is a hydraulic pressure signal at the axle drive. 
     
     
         9 . The compaction system of  claim 7 , wherein the sensor is operatively coupled to the roller and the signal is a hydraulic pressure signal at the roller. 
     
     
         10 . The compaction system of  claim 1 , wherein the power source is an electric drive system and the signal is an electric potential signal. 
     
     
         11 . The compaction system of  claim 10 , wherein the sensor is operatively coupled to an axle drive of the propulsion device and the signal is the electric potential signal at the axle drive. 
     
     
         12 . The compaction system of  claim 1 , wherein the first variance is a first peak-to-peak variance of the signal during the first time duration and the second variance is a second peak-to-peak variance of the signal during the second time duration. 
     
     
         13 . The compaction system of  claim 1 , wherein the first variance is a first average frequency of the signal during the first time duration and the second variance is a second average frequency of the signal during the second time duration. 
     
     
         14 . The compaction system of  claim 1 , wherein the first variance is a first average frequency variance of the signal during the first time duration and the second variance is a second average frequency variance of the signal during the second time duration. 
     
     
         15 . A method for determining decoupling of a roller from a work material, the method comprising:
 compacting the work material with a roller driven by a propulsion device;   receiving a signal from a sensor, the signal indicative of a power potential of a power source operatively coupled to the propulsion device;   determining a first variance for a first time duration of the signal;   determining a second variance for a second time duration of the signal; and   determining the roller is decoupled from the work material based on at least one of the first variance and the second variance.   
     
     
         16 . The method of  claim 15 , further comprising:
 comparing the first variance and the second variance; and   determining the roller is decoupled from the work material when a difference between the first variance and the second variance exceeds a threshold.   
     
     
         17 . The method of  claim 15 , further comprising determining the roller is decoupled from the work material when a magnitude of the second variance exceeds a first threshold. 
     
     
         18 . The method of  claim 15 , further comprising forwarding an alert to an operator, the alert indicating that the roller is decoupled from the work material. 
     
     
         19 . The method of  claim 15 , further comprising adjusting the power potential of the power source when the roller is decoupled from the work material. 
     
     
         20 . An article of manufacture comprising non-transitory machine-readable media having instructions encoded thereon for causing a controller to:
 forward instructions to compact a work material with a roller driven by a propulsion device;   receive a signal from a sensor, the signal indicative of a power potential of a power source operatively coupled to the propulsion device;   determine a first variance for a first time duration of the signal;   determine a second variance for a second time duration of the signal; and   determine a roller is decoupled from the work material based on at least one of the first variance and the second variance.