Work vehicle magnetorheological fluid joystick systems providing machine state feedback

Abstract

Embodiments of a work vehicle magnetorheological fluid (MRF) joystick system include a joystick device, an MRF joystick resistance mechanism, a controller architecture, and a work vehicle sensor configured to provide sensor data indicative of an operational parameter pertaining to work vehicle. The MRF joystick resistance mechanism is controllable to vary an MRF resistance force resisting movement of a joystick included in the joystick device relative to a base housing thereof. The controller architecture is configured to: (i) monitor for variations in the operational parameter utilizing the sensor data; and (ii) provide tactile feedback through the joystick device indicative of the operational parameter by selectively commanding the MRF joystick resistance mechanism to adjust the MRF resistance force impeding joystick movement based, at least in part, on variations in the operational parameter.

What is claimed is: 
     
         1 . A work vehicle magnetorheological fluid (MRF) joystick system utilized onboard a work vehicle, the work vehicle MRF joystick system comprising:
 a joystick device, comprising:
 a base housing; 
 a joystick movably mounted to the base housing; and 
 a joystick position sensor configured to monitor movement of the joystick relative to the base housing; 
   an MRF joystick resistance mechanism controllable to vary an MRF resistance force impeding joystick movement relative to the base housing in at least one degree of freedom;   a work vehicle sensor configured to provide sensor data indicative of an operational parameter pertaining to work vehicle; and   a controller architecture coupled to the joystick position sensor, to the MRF joystick resistance mechanism, and to the work vehicle sensor, the controller architecture configured to:
 monitor for variations in the operational parameter utilizing the sensor data; and 
 provide tactile feedback through the joystick device indicative of the operational parameter by selectively commanding the MRF joystick resistance mechanism to adjust the MRF resistance force based, at least in part, on variations in the operational parameter. 
   
     
     
         2 . The work vehicle MRF joystick system of  claim 1 , wherein the operational parameter comprises a hydraulic load placed on the work vehicle; and
 wherein the controller architecture is configured to command the MRF joystick resistance mechanism to increase the MRF resistance force as the hydraulic load increases.   
     
     
         3 . The work vehicle MRF joystick system of  claim 1 , wherein the work vehicle comprises an electrohydraulic (EH) actuation system and an implement movable utilizing the EH actuation system;
 wherein the operational parameter comprises a circuit pressure of the EH actuation system; and   wherein the work vehicle sensor comprises a pressure sensor configured to monitor the circuit pressure.   
     
     
         4 . The work vehicle MRF joystick system of  claim 1 , wherein the work vehicle comprises a load-carrying component;
 wherein the operational parameter comprises a material weight borne by load-carrying component; and   wherein the controller architecture is configured to command the MRF joystick resistance mechanism to increase the MRF resistance force as the material weight increases.   
     
     
         5 . The work vehicle MRF joystick system of  claim 4 , wherein the load-carrying component of the work vehicle comprises a boom-mounted implement; and
 wherein the controller architecture is configured to increase the MRF resistance force in a manner impeding joystick movements raising the boom-mounted implement.   
     
     
         6 . The work vehicle MRF joystick system of  claim 4 , wherein the load-carrying component comprises a receptacle of the work vehicle; and
 wherein the operational parameter comprises a payload weight held by the receptacle.   
     
     
         7 . The work vehicle MRF joystick system of  claim 1 , wherein the work vehicle comprises a bucket;
 wherein the work vehicle sensor is configured to monitor a current fill weight of the bucket; and   wherein the controller architecture is configured to:
 establish a target tipoff weight to which the bucket is desirably filled; and 
 selectively vary the MRF resistance force based of a differential between the target tipoff weight and the current fill weight of the bucket. 
   
     
     
         8 . The work vehicle MRF joystick system of  claim 1 , wherein the operational parameter comprises a ground speed of the work vehicle; and
 wherein the controller architecture is configured to command the MRF joystick resistance mechanism to increase the MRF resistance force as the ground speed of the work vehicle increases.   
     
     
         9 . The work vehicle MRF joystick system of  claim 8 , wherein the MRF resistance force impedes joystick movement controlling at least one of work vehicle heading and work vehicle ground speed. 
     
     
         10 . The work vehicle MRF joystick system of  claim 1 , wherein the work vehicle comprises a movable component having motion stop point;
 wherein the operational parameter comprises displacement of the movable component relative to the motion stop point; and   wherein the controller architecture is configured to command the MRF joystick resistance mechanism to selectively increase the MRF resistance force as the movable component approaches the motion stop point.   
     
     
         11 . The work vehicle MRF joystick system of  claim 10 , wherein the movable component comprises a hydraulic cylinder having a stroke limit or an articulable joint of a boom assembly. 
     
     
         12 . The work vehicle MRF joystick system of  claim 1 , wherein the work vehicle comprises an electrohydraulic (EH) actuation system containing a pilot valve; and
 wherein the controller architecture is configured to command the MRF joystick resistance mechanism to selectively vary the MRF resistance force in a manner providing tactile feedback indicating when the pilot valve initially opens.   
     
     
         13 . The work vehicle MRF joystick system of  claim 1 , wherein the joystick device is utilized to control movement of the work vehicle;
 wherein the operational parameter comprises a current motion state of the work vehicle; and   wherein the controller architecture is configured to:
 determine when motion of the joystick in an operator input direction at a detected rate will result in an undesirably abrupt change in the current motion state of the work vehicle; and 
 when determining when motion of the joystick in an operator input direction at a detected rate will result in an undesirably abrupt change in the current motion state of the work vehicle, command the MRF joystick resistance mechanism to increase the MRF resistance force to impede continued movement of the joystick in the operator input direction. 
   
     
     
         14 . The work vehicle MRF joystick system of  claim 13 , wherein the joystick device is utilized to control at least one of a ground speed of the work vehicle and a heading of the work vehicle. 
     
     
         15 . The work vehicle MRF joystick system of  claim 13 , wherein the work vehicle comprises boom assembly attached to a chassis of the work vehicle; and
 wherein the joystick device is utilized to control movement of the boom assembly.   
     
     
         16 . A work vehicle magnetorheological fluid (MRF) joystick system utilized onboard a work vehicle, the work vehicle MRF joystick system comprising:
 a joystick device, comprising:
 a base housing; 
 a joystick movably mounted to the base housing; and 
 a joystick position sensor configured to monitor movement of the joystick relative to the base housing; 
   an MRF joystick resistance mechanism controllable to vary an MRF resistance force impeding joystick movement relative to the base housing in at least one degree of freedom; and   a controller architecture coupled to the joystick position sensor and to the MRF joystick resistance mechanism, the controller architecture configured to:
 monitor a current ground speed of the work vehicle; and 
 selectively command the MRF joystick resistance mechanism to adjust the MRF resistance force based, at least in part, on the current ground speed of the work vehicle. 
   
     
     
         17 . The work vehicle MRF joystick system of  claim 16 , wherein the controller architecture is configured to command the MRF joystick resistance mechanism to progressively increase the MRF resistance force impeding joystick rotation about a first axis as the current ground speed of the work vehicle increases. 
     
     
         18 . The work vehicle MRF joystick system of  claim 17 , wherein the joystick device is controllable is steer the work vehicle by rotation of the joystick about the first axis. 
     
     
         19 . A work vehicle magnetorheological fluid (MRF) joystick system utilized onboard a work vehicle having a boom-mounted implement, the work vehicle MRF joystick system comprising:
 a joystick device, comprising:
 a base housing; 
 a joystick movably mounted to the base housing; and 
 a joystick position sensor configured to monitor movement of the joystick relative to the base housing; 
   an MRF joystick resistance mechanism controllable to vary an MRF resistance force impeding joystick movement relative to the base housing in at least one degree of freedom; and   a controller architecture coupled to the joystick position sensor and to the MRF joystick resistance mechanism, the controller architecture configured to:
 estimate a variable load resisting movement of the boom-mounted implement in at least one direction; and 
 selectively command the MRF joystick resistance mechanism to increase the MRF resistance force as the variable load increases. 
   
     
     
         20 . The work vehicle MRF joystick system of  claim 19 , wherein the variable load comprises a material weight carried by the boom-mounted implement; and
 wherein the controller architecture is configured to command the MRF joystick resistance mechanism to increase the MRF resistance force in a manner impeding joystick motions raising the boom-mounted implement.