Adjustment Guideline for ScrewTighten Sequence and Object Property Values

The following section describes how to adjust when using ScrewTighten sequence and objects.

• If GeneralObjectFailed appears as the FailedStatus result:
  A failure has occurred with a general object placed in the ScrewTighten sequence. The last executed object appears in the LastExecObject result. Adjust the property of the object that appears here by referring to the property setting guideline or adjustment guideline for the property.

• If CollisionDetect appears as the FailedStatus result:
  A failure has occurred because the force met the force failure condition set by the object during sequence execution.

• If the ScrewTighten object appears as the LastExecObject result:
  The screw may have been tightened in a position where it is not in the screw hole. Check the operation start point and teach again.
  If the teaching is correct, increase the CollisionForceThresh value. If the CollisionForceThresh is small, it may be falsely detected as a collision due to the force applied during screw tightening.

• If the ScrewRetighten object appears as the LastExecObject result:
  Increase the CollisionForceThresh value. If the CollisionForceThresh is small, it may be falsely detected as a collision due to the force applied during screw retightening.

• If Overrun appears as the FailedStatus result:
  Even though the position exceeded the position success condition range set by the object during the ScrewTighten object or ScrewRetighten object execution, a position overrun was detected and a failure has occurred because the motion executed without receiving the screw tightening completion signal.
  Check that the ApproachDist and ScrewLength values are not too small compared to the actual operating environment.

• If Jammed appears as the FailedStatus result:
  A jamming failure has occurred because the position did not meet the position success condition at the point when the screw tightening completion signal is received during the ScrewTighten object or ScrewRetighten object execution.
  The screw may be at too much of a tilt toward the screw hole. Check the orientation of the screw at the start point of the motion, and redo the teaching process.
  If the teaching is correct, check that the ApproachDist and ScrewLenth values are not too large compared to the actual operating environment.

• NoOKSignal appears as the FailedStatus result:
  If the screw tightening completion signal cannot be received during execution of the sequence, it is determined that the completion signal has not been received and it has failed.
  Make sure that the screw tightening completion bit is set correctly in the robot hand settings.

• If the driver bit comes out from screw hole during screw retightening:
  Increase the AddRetightenPressForce value. However, the pressing force during screw tightening will increase, adjust it to an appropriate value.

• When the robot motion vibrates:
  Increase the Firmness value. However, response of the robot will be slow. Please perform proper adjustments for your operations.
  To adjust the Firmness, we recommend changing the value gradually (e.g. increase the value by 10% from its present state).

• When the robot bounces largely in the pressing direction:
  If the robot repeatedly bounces largely in a few seconds, the robot motion may be restricted by LimitAccelS of the force guide sequence.
  Also, it likely to happen during the execution in low power mode.
  If the robot still bounces even executing in high power mode, increase the value of LimitAccelS. If the robot still bounces, decrease the value of Firmness in pressing direction.

• When the robot does not reach to the target force:
  Decrease the Firmness value of the pressing direction.
  However, the robot motion may be easy to vibrate. Please perform proper adjustments for your operations.
  To adjust the Firmness, we recommend changing the value gradually (e.g. decrease the value by 10% from its current state).

• When the robot does not move to the pressing direction:
  Confirm that the ControlMode where the robot does not move is either Press+ or Press-.
  When Press+ or Press- is set, confirm whether the PressForce is set to "0".

• When the robot moves in the reverse direction:
  Confirm that the ControlMode where the robot moves in the reverse direction is either Press+ or Press-.
  When the robot is set to assumed direction, confirm the ForceOrient or RobotLocal of the force guide sequence, tool coordinate system, or local coordinate system.

• When the robot does not reach to the destination point:
  If the direction where the force control functions are not enabled is not reached to the destination point, it may be affected by the LimitAccel or LimitSpeed of the force guide sequence. Increase the value.
  Also, in low power mode, it is restricted according to the maximum speed or maximum acceleration of the low power mode even the value of LimitSpeed or LimitAccel is large. Be sure to execute in high power mode.