Symptom:
Finger sticks fully closed.
Possible Solution:
1.
Verify there are no objects or other fingers blocking the finger from opening completely.
2.
The open velocity is too slow. Try increasing the open velocity to greater than or equal
to 40 and opening the finger.
3.
Verify that the strain gage value SG is less than HSG (High Strain Gage Limit; alias is
MSG).
4.
If the strain gages are not installed set HSG to 256 for the BH8-262 and set HSG to 0 for
BH8-280 hands.
5.
The pretension in the cable is too high. Refer to Section 7.1 to set the finger cable
pretension properly.
6.
Set the open velocity greater than or equal to 40 and then initialize the finger.
7.
Reload firmware.
8.
If the problem persists, contact Barrett Technology.
Symptom:
Finger sticks open.
Possible Solution:
1.
Verify there are no objects or other fingers blocking the finger from closing.
2.
The close velocity is set too low. Try increasing the close velocity to greater than or
equal to 40 and closing the finger.
3.
Set the close velocity to greater than or equal to 40 and then initialize the finger.
4.
Reload firmware.
5.
If the problem persists, contact Barrett Technology.
Symptom:
Finger moves in opposite direction of commanded motion.
Possible Solution:
1.
Reload firmware.
2.
There is an encoder feedback problem. Reinitializing the finger should solve the
immediate problem. If this recurs, contact Barrett Technology for servicing.
Symptom:
The TorqueSwitch™ does not breakaway properly, prohibiting the fingertip
from completing a form grasp around an object.
Possible Solution:
1.
The close velocity is too slow. Increase the close velocity greater than or equal to 40.
2.
Reinitialize the finger; this may reset the TorqueSwitch™.
3.
If the BarrettHand™ has been inactive for an extended period or if the finger has been
slammed open against its stop with a high velocity setting, the TorqueSwitch™ may need to
be manually activated. Insert a 2-mm hex wrench into the left Drive Access hole, as shown
in Figure 27. Rotate counterclockwise to open the finger fully. Next, press very hard against
the inner link to constrain it from moving while not constraining the outer link, as the person’s
thumb is doing in Figure 26, while torqueing the hex wrench clockwise. Increase torque until
the fingertip breaks free, so that it can be rotated easily while the inner link remains
stationary. Remove the 2-mm hex wrench and reinitialize the finger.
4.
If the problem persists, contact Barrett Technology.
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