Sanding system with damping feature

Abstract

A sanding system is presented that includes a tool with a motor which, when actuated, drives movement of a drive shaft. The system also includes a backup pad coupled to the drive shaft. The backup pad is configured to receive an abrasive article. Movement of the drive shaft causes movement of the abrasive article. The system also includes a compliant damping unit configured to provide variable compliance for the tool when the abrasive article contacting a worksurface. The system also includes an electronic controller that receives a system operating condition and sends a signal to the compliant damping unit based on the system operating condition.

1 . A sanding system comprising:
 a tool with a motor which, when actuated, drives movement of a drive shaft;   a backup pad coupled to the drive shaft, wherein the backup pad is configured to receive an abrasive article, and wherein movement of the drive shaft causes movement of the abrasive article;   a compliant damping unit configured to provide variable compliance for the tool when the abrasive article contacting a worksurface; and   an electronic controller that receives a system operating condition, sends a signal to the compliant damping unit based on the system operating condition.   
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . The sanding tool of  claim 1 , wherein the system operating condition is received from a sensor associated with the damping unit, a sensor associated with the motor, an end effector to which the sanding tool is coupled, or a vision system. 
     
     
         5 . The sanding tool of  claim 4 , wherein the system operating condition is a measured reaction force, an orientation of the tool with respect to the worksurface, an indication that the abrasive article has contacted a worksurface, or a vibration threshold. 
     
     
         6 . (canceled) 
     
     
         7 . (canceled) 
     
     
         8 . (canceled) 
     
     
         9 . The system of  claim 1 , wherein the magnetorheological fluid is housed in the backup pad and wherein the current is applied to a contact ring on a surface of the backup pad. 
     
     
         10 . The system of  claim 9 , wherein the magnetorheological fluid is contained by a fluid bladder, and wherein the tool housing comprises a wire wound about the fluid bladder, and wherein the wire is configured to produce a magnetic field when a current is received. 
     
     
         11 . The system of  claim 9 , wherein the fluid bladder is positioned above the motor such that the motor can move in a single axis. 
     
     
         12 . (canceled) 
     
     
         13 . (canceled) 
     
     
         14 . The system of  claim 1 , wherein the compliant damping unit comprises a ball-bearing feature. 
     
     
         15 . The system of  claim 14 , wherein the ball-bearing feature comprises magnetorheological shock absorbers coupled between a sander housing and the backup pad. 
     
     
         16 . The system of  claim 14 , wherein the ball-bearing feature comprises a groove in a backup pad housing that a ball-bearing moves in when the motor is actuated. 
     
     
         17 . The system of  claim 1 , wherein the drive shaft is a telescoping drive shaft, and wherein the compliant damping unit comprises a rheological damping device that can collapse or extend with the telescoping drive shaft. 
     
     
         18 . (canceled) 
     
     
         19 . The system of  claim 1 , wherein the sanding system is mounted to a robotic arm. 
     
     
         20 . A method of mechanically sanding a surface, the method comprising:
 providing a sanding tool coupled to an abrasive article;   contacting the abrasive article to a worksurface; and   varying compliance of the sanding tool during an abrasive operation comprising the abrasive article contacting a worksurface, wherein varying compliance comprises controlling a compliant damping feature, wherein the compliant damping feature adjusts an applied force of the sanding tool; and   wherein an electronic control system actuates the mechanical damping feature in response to a system operating condition received from a sensor.   
     
     
         21 . (canceled) 
     
     
         22 . The method of  claim 20 , wherein controlling comprises increasing an applied current which increases the applied force of the sanding tool and wherein the sanding tool comprises a telescoping drive shaft and wherein the damping unit comprises a magnetorheological damping device that can collapse or expand with the telescoping drive shaft. 
     
     
         23 . The method of  claim 20 , wherein controlling comprises decreasing an applied current which decreases the applied force of the sanding tool. 
     
     
         24 . The method of  claim 20 , and further comprising:
 actuating the sanding tool, wherein actuation causes a motor to drive a drive shaft which causes motion of a backup pad which is coupled to the abrasive article.   
     
     
         25 . The method of  claim 23 , wherein actuation of the motor causes actuation of the electronic controller. 
     
     
         26 . The method of  claim 20 , wherein the system operating condition is received from a sensor associated with the compliant damping feature, a sensor associated with the motor, or a vision system remote from the sanding tool and wherein the system operating condition is a measured reaction force, a motor actuation signal, an indication that the abrasive article has contacted a worksurface, or an indication that detected vibrations exceed a vibration threshold. 
     
     
         27 - 35 . (canceled) 
     
     
         36 . The method of  claim 20 , wherein the compliant damping unit comprises a magnetorheological shock absorber. 
     
     
         37 . The method of  claim 36 , wherein the magnetorheological shock absorber is coupled between a sander housing and the backup pad. 
     
     
         38 - 42 . (canceled) 
     
     
         43 . A damping system for a sanding tool, the system comprising:
 a fluid-based damping feature;   an electronic controller that receives a sanding operation signal and, based on the sanding operation signal, actuates the fluid-based damping feature; and   wherein actuating the fluid-based damping feature comprises changing a physical parameter of a fluid in the fluid-based damping feature.