TL;DR

End-effector misalignment on the R-2000iC is almost always TCP calibration drift from tool wear or a tool mounting shift. Verify tool geometry against the defined TCP before touching up program points.

What you might see

gripper or tool misses the target position
TCP position error alarm on controller
tool consistently offset in one direction
part placement or pickup drifts during a shift

Likely causes

Tap to mark as ruled out

Tool Center Point (TCP) calibration drift from tool tip wear or deformation
Tool mounting bolts loose on the wrist flange allowing tool shift
Wrist flange damaged or distorted from a collision event
Tool itself worn or deformed, no longer matching the calibrated geometry

Required tools

FANUC R-30iB controller access (tool frame and TCP calibration menu)
Calibration pointer or reference sphere for TCP procedure
Torque wrench (wrist flange bolt torque spec)
Dial indicator (for flange face runout check)
LOTO kit
FANUC R-2000iC Maintenance Manual

Safety first

Use T1 mode and the deadman switch for all TCP calibration work inside the safety fence. Maximum allowable speed inside the fence is 250 mm/s.
Lock out the controller before inspecting or torquing any tool mounting hardware.
After any TCP recalibration, run the robot through the full program in T1 mode before returning to automatic production speed.

Procedure

8 steps · ~45 min

1
Check the FANUC controller for any TCP error alarm or tool number mismatch. Record the current TCP data for the active tool from the tool frame menu.[1]
2
Physically inspect the tool tip or reference feature for wear or deformation. Compare the tool geometry to the as-calibrated drawing.
3
Inspect the tool mounting bolts at the wrist flange. Re-torque any loose bolts to the FANUC flange torque specification. Recheck TCP after torquing.[1]
4
Inspect the wrist flange face for impact damage or distortion from a collision. A damaged flange face prevents the tool from mounting true.
5
If the tool geometry is unchanged and mounting is secure, re-run the TCP calibration procedure using the FANUC four-point or six-point method.
6
After TCP calibration, jog the robot to a fixed reference point and confirm the TCP is within the required accuracy for the application.
7
If accuracy is confirmed at the reference point but program points are offset, the program points need to be touched up, do not adjust TCP to compensate for program errors.
8
If the wrist flange is damaged, replace the flange and re-run TCP calibration before resuming production.

Sources

FANUC R-2000iC Robotic Arm Maintenance Manual, FANUC
FANUC R-2000iC Robot Maintenance Manual, tool center point calibration and wrist flange procedures (general)
View source

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