Grinding/polishing systems and methods having proximity sensors

Abstract

An example grinder/polisher system includes: a specimen holder configured to secure a specimen; a platen; an actuator configured to move at least one of the specimen holder and the platen; a sensor configured to detect objects within a field of view of the sensor; and a controller configured to control movement of the actuator and to stop the actuator in response to detection of an object by the sensor while the actuator is moving.

What is claimed is: 
     
         1 . A grinder/polisher system, comprising:
 a specimen holder configured to secure a specimen;   a platen;   an actuator configured to move at least one of the specimen holder and the platen;   a sensor configured to detect objects within a field of view of the sensor; and   a controller configured to control movement of the actuator and to stop the actuator in response to detection of an object by the sensor while the actuator is moving.   
     
     
         2 . The grinder/polisher system of  claim 1 , wherein the controller is configured to:
 identify a background signal from the sensor in response to initiation of an operation involving movement by the actuator; and   detect an object based on comparing a monitoring signal from the sensor to the background signal.   
     
     
         3 . The grinder/polisher system of  claim 2 , wherein the controller is configured to detect the object when a difference between the monitoring signal and the background signal satisfies a threshold. 
     
     
         4 . The grinder/polisher system of  claim 1 , wherein the actuator comprises a motor and a driver actuator, the controller further configured to control (i) the motor to rotate at least one of the specimen holder and the platen in accordance with selected grinding/polishing parameters, and (ii) the drive actuator to press the specimen or the platen into the other of the specimen and the platen in accordance with a selected load applied. 
     
     
         5 . The grinder/polisher system of  claim 4 , further comprising a user interface, the controller configured to output a notification via the user interface in response to the detection of the object. 
     
     
         6 . The grinder/polisher system of  claim 1 , wherein the sensor comprises at least one of an ultrasonic sensor, a retroreflective proximity sensor, an optical sensor, or a light curtain sensor. 
     
     
         7 . The grinder/polisher system of  claim 1 , further comprising a plurality of sensors including the sensor, the plurality of sensors configured to monitor a corresponding plurality of sub-volumes proximate the platen. 
     
     
         8 . The grinder/polisher system of  claim 1 , wherein the controller is configured to disable the actuator until detection, via the sensor, of removal of the object. 
     
     
         9 . A method to control a grinder/polisher system, the method comprising:
 controlling, via a controller, an actuator to move at least one of a specimen holder and of a grinder/polisher system or a platen of the grinder/polisher system; and   in response to detecting, via a sensor, an object within a field of view of the sensor while the actuator is moving, controlling the actuator to stop.   
     
     
         10 . The method of  claim 9 , further comprising:
 identifying a background signal from the sensor in response to initiation of an operation involving movement by the actuator; and   detecting an object based on comparing a monitoring signal from the sensor to the background signal.   
     
     
         11 . The method of  claim 10 , wherein detecting the object occurs when a difference between the monitoring signal and the background signal satisfies a threshold. 
     
     
         12 . The method of  claim 9 , wherein controlling the actuator comprises controlling (i) a motor of the actuator to rotate at least one of the specimen holder and the platen in accordance with selected grinding/polishing parameters, and (ii) a drive actuator of the actuator to press the specimen or the platen into the other of the specimen and the platen in accordance with a selected load applied. 
     
     
         13 . The method of  claim 12 , further comprising outputting a notification via a user interface in response to the detection of the object. 
     
     
         14 . The method of  claim 9 , wherein detecting the object via the sensor comprises detecting the object via at least one of an ultrasonic sensor, a retroreflective proximity sensor, an optical sensor, or a light curtain sensor. 
     
     
         15 . The method of  claim 9 , wherein detecting the object via the sensor comprises detecting the object via at least one of a plurality of sensors configured to monitor a corresponding plurality of sub-volumes proximate the platen. 
     
     
         16 . The method of  claim 9 , further comprising disabling the actuator until detection, via the sensor, of removal of the object.