Articulating device

Abstract

Disclosed is a method of moving an articulating mechanism ( 22,410 ) for a measuring device, comprising the steps of: releasing two bodies ( 14,16, 410 a, 410 b) which form the articulating mechanism allowing relative movement thereof; moving one of the bodies with respect to the other until a desired position is reached; and re-constraining the two bodies so they are relatively fixed, perhaps as part of a locking process, characterised in that relative movement prior to re-constraining at the desired position occurs under particular conditions. The particular conditions including moving from the same direction; and stopping, slowing down or maintaining the condition at a position adjacent to the desired position. Also disclosed is a method of positioning an articulating mechanism ( 22,410 ) for a measuring device which is controlled by a potentiometer and a controller ( 11 ) for a measuring device.

The invention claimed is: 
     
       1. A method of moving an articulating mechanism for a measuring device, comprising the steps of:
 releasing two bodies which form the articulating mechanism allowing relative movement thereof; 
 moving one of the bodies with respect to the other until a desired position is reached wherein the relative movement occurs under particular conditions; and 
 re-constraining the two bodies so they are relatively fixed, characterized in that the relative movement prior to re-constraining at the desired position is a part of a locking process. 
 
     
     
       2. A method according to  claim 1 , wherein the particular conditions includes moving from particular direction. 
     
     
       3. A method according to  claim 1  wherein, the particular conditions includes controlling the movement at a position adjacent to the desired position. 
     
     
       4. A method according to  claim 1  wherein, the particular conditions includes stopping, slowing down or maintaining at a consistently used speed at a position adjacent the desired position. 
     
     
       5. A method according to  claim 1  wherein, the step of:
 releasing the two bodies comprises disengaging co-operating surfaces of two bodies which form the articulating mechanism; and 
 re-constraining the two bodies comprises re-engaging the co-operating surfaces of the two bodies so they are relatively fixed. 
 
     
     
       6. A method of moving an articulating mechanism for a measuring device, the method comprising:
 (a) releasing two bodies which form the articulating mechanism allowing relative movement thereof; 
 (b) moving one of the two bodies with respect to the other until a position adjacent a desired position is reached; 
 (c) moving one of the two bodies with respect to the other from the position adjacent to the desired position to the desired position whereby said movement occurs under particular conditions; and 
 (d) re-constraining the two bodies so they are relatively fixed characterized in that the relative movement prior to re-constraining at the desired position is a part of a locking process. 
 
     
     
       7. A method according to  claim 6  wherein, between steps (a) and (b) is the additional step of moving one of the two bodies with respect to the other until the desired position is reached. 
     
     
       8. A method according to  claim 6  wherein, the step of:
 releasing the two bodies comprises disengaging co-operating surfaces of two bodies which form the articulating mechanism; and 
 re-constraining the two bodies comprises re-engaging the co-operating surfaces of the two bodies so they are relatively fixed. 
 
     
     
       9. A method of positioning an articulating mechanism for a measuring device which is controlled by a potentiometer, the method comprising:
 moving the articulating mechanism to a position under particular conditions; 
 recording a signal indicative of that position; and 
 repeating for other positions; characterized in that, during a subsequent movement to the position carried out under the same particular conditions, a signal indicative of the position is obtained, compared with the recorded signal and the articulating mechanism is moved until the indicative signal corresponds to the recorded signal. 
 
     
     
       10. A method according to  claim 9 , wherein the particular conditions includes approaching the position from particular direction. 
     
     
       11. A method according to  claim 9 , wherein any difference between the recorded and indicative signal is flagged. 
     
     
       12. A method according to  claim 9  wherein, if the articulating mechanism is moved to a location which is between positions, the recorded signal is interpolated. 
     
     
       13. A method according to  claim 9 , wherein the articulating mechanism is locked when the indicative signal corresponds to the recorded signal. 
     
     
       14. A measuring device comprising:
 an articulating mechanism having two bodies which can be relatively fixed or relatively moveable; 
 a controller which includes a comparator for comparing current device position with a desired position; and 
 means to control motion of the device such that it always moves to the desired position under particular conditions as part of a locking procedure to re-constrain the two bodies so they are relatively fixed. 
 
     
     
       15. A probe comprising a measuring device according to  claim 14 . 
     
     
       16. A measuring machine comprising a measuring device according to  claim 14 . 
     
     
       17. A method of positioning an articulating mechanism for a measuring device comprising two bodies which are relatively movable and lockable in each of a plurality of defined positions, a reading being provided which is indicative of the relative position of the two bodies, the method comprising:
 (a) unlocking the two bodies;   (b) comparing a current reading indicative of relative position of the two bodies with a recorded reading thereof and moving the two bodies until the current reading corresponds to the recorded reading, the recorded reading having been recorded when the two bodies of the articulating device were locked; and   (c) locking the two bodies.   
     
     
       18. A method according to claim 17, wherein recorded readings for the plurality of defined positions are recorded in a table. 
     
     
       19. A method according to claim 17, including recording the readings when the bodies are locked in the plurality of defined positions. 
     
     
       20. A method according to claim 17, wherein the articulating mechanism comprises two sets of detent elements, one set on each body, the detent elements being mutually engaged when the bodies are locked in the defined positions, and being released when the bodies are unlocked. 
     
     
       21. An articulating mechanism for a measuring device comprising:
 two relatively movable bodies which can be locked and unlocked in a plurality of defined positions; and   a controller configured to:
 access recorded readings indicative of the relative position of the two bodies when the bodies are locked in each of the plurality of defined positions; 
 compare a current position reading for the two relatively movable bodies with an accessed recorded reading; and 
 control movement of the two relatively movable bodies, the movement of the bodies being stopped and locked when there is no difference between the current position and the accessed recorded reading. 
   
     
     
       22. An articulating mechanism according to claim 21, wherein the readings indicative of the relative position of the two bodies when the bodies are locked are recorded in a table. 
     
     
       23. An articulating mechanism according to claim 21, wherein the articulating mechanism comprises two sets of detent elements, one set on each body, the detent elements being mutually engaged when the bodies are locked in the defined positions, and being released when the bodies are unlocked. 
     
     
       24. A measuring machine including an articulating mechanism for a measuring device, wherein:
 the articulating mechanism comprises two relatively movable bodies which can be locked and unlocked in a plurality of defined positions; and   the measuring machine comprises a controller configured to:
 access recorded readings indicative of the relative position of the two bodies when the bodies are locked in each of the plurality of defined positions; 
 compare a current position reading for the two relatively movable bodies with an accessed recorded reading; and 
 control movement of the two relatively movable bodies, the movement of the bodies being stopped and locked when there is no difference between the current position and the accessed recorded reading. 
   
     
     
       25. A measuring machine according to claim 24, wherein the readings indicative of the relative position of the two bodies when the bodies are locked are recorded in a table. 
     
     
       26. A measuring machine according to claim 24, wherein the articulating mechanism comprises two sets of detent elements, one set on each body, the detent elements being mutually engaged when the bodies are locked in the defined positions, and being released when the bodies are unlocked. 
     
     
       27. A method of positioning an articulating mechanism for a measuring device, the articulating mechanism comprising first and second bodies, the second body being movable relative to the first body; and two sets of detent elements, one set on each body; the detent elements being mutually engageable in a plurality of defined positions of the second body relative to the first body; the detent elements being releasable so that the second body can be moved relative to the first body and re-engageable so that the bodies are relatively fixed in a new one of the defined positions, the positioning method comprising:
 (a) moving the articulating mechanism to one of the positions and engaging the detent elements;   (b) recording a signal indicative of the position at which the detent elements were engaged in (a); and   (c) repeating (a) and (b) for other ones of the positions;   (d) during a subsequent movement to one of the positions:
 obtaining a signal indicative of that position; 
 comparing the obtained signal with a corresponding recorded signal; 
 moving the articulating mechanism until the indicative signal corresponds to the recorded signal; and 
 re-engaging the elements when the indicative signal corresponds to the recorded signal. 
   
     
     
       28. A method according to claim 27 wherein the one of the positions is approached from the same direction during the subsequent movement as in (a). 
     
     
       29. A method according to claim 27 further comprising flagging when the signal received when the detent elements of the articulating mechanism are re-engaged does not tally with an expected result. 
     
     
       30. A method according to claim 27 wherein, if the articulating mechanism is moved to a location which is between positions, the recorded signal is interpolated. 
     
     
       31. A method according to claim 27 wherein, in (b), the signals indicative of the positions are recorded in a table. 
     
     
       32. A method according to claim 27 wherein (b) is performed while the detent elements are engaged in the position. 
     
     
       33. A measuring device, comprising:
 an articulating mechanism comprising:
 first and second bodies, the second body being movable relative to the first body; and 
 two sets of detent elements, one set on each body, the detent elements being mutually engageable in a plurality of defined positions of the second body relative to the first body, the detent elements being releasable so that the second body can be moved relative to the first body and re-engageable so that the bodies are relatively fixed in a new one of the defined positions; and 
   a controller which includes a comparator for comparing the current relative position of the movable bodies with a recorded signal indicative of a desired position, the controller being configured to:
 (a) move the articulating mechanism to one of the positions and engage the detent elements; 
 (b) record a signal indicative of the position at which the detent elements were engaged in (a); and 
 (c) repeat (a) and (b) for other ones of the positions; and 
 (d) during a subsequent movement to one of the positions:
 compare a signal indicative of that position with a corresponding recorded signal; 
 move the articulating mechanism until the indicative signal corresponds to the recorded signal; and 
 re-engage the elements when the indicative signal corresponds to the recorded signal.