Operate the Real Arm · xArm 850 · Step 6 of 9
Respond to an Abnormal Condition
Something will go wrong sooner or later. What matters is the order: make it safe first, then find the cause, then recover, with lab staff. Never create a fault on purpose to practice this: use the simulator.
The Rule for Every Error
- When an error occurs, the arm stops at once and throws away its queued commands. The error must be cleared by hand and the motion re-planned before normal work goes on1.
- Stop the arm and ask for help whenever its condition is uncertain2.
- Before any restart, make sure the restart motions will not hit anything3.
Warning
Common Conditions
| Condition | How it is detected | Immediate safe response | Likely cause | Recovery procedure |
|---|---|---|---|---|
| The control box's emergency stop is pressed | Studio shows a Controller Error, error code C1: the emergency stop button on the control box is pushed in6 | Keep clear. The arm loses power, brakes slightly and falls, and a card it holds can drop789 | Someone pressed the button: in an emergency, or by accident10 | With lab staff, find out why it was pressed and make sure the restart motions will not hit anything. Turn the button in the direction of its arrow to release it, then click Enable Robot3116 |
| A collision stop | The arm stops, and Studio shows error code C31, abnormal current in the arm, with the joint, its torque, the collision sensitivity, the payload and the mounting setting12. With collision rebound on, the arm first moves back a little1314 | Click STOP and keep clear. Press the emergency stop if anyone is hurt or at risk1510 | The arm hit something, or the payload or mounting setting does not match the real arm, which causes false collision alarms1216 | Check whether the arm really collided, and clear the obstacle12. Lab staff decide what else to check, such as the payload and mounting settings; then the error is cleared and the move re-planned2161 |
| Loss of communication between the computer and the arm | With Network Monitoring on, Studio checks whether the connection is interrupted while you hold a motion button in Live Control17. A Python program gets code A-1, robot not connected18 | If the arm is moving and Studio does not respond, press the emergency stop107 | The network cable is out or damaged, the computer's address is wrong, or a wireless link is in use192021 | Reconnect the cable directly to the control box, check your computer's address1920, then in Studio enter the arm's address in the IP search field and click Connect Server again22. Read the arm's state before any move23 |
| The suction does not hold, or the card drops | The card does not lift, or falls while carried. In a Blockly program with object detection on, the program stops when the card is not held24 | Click STOP. Do not reach for the card until the arm has stopped1525 | The cup was not on the card, the card is misplaced, suction was not switched on, or the tool is loose. A gripper that holds unstably can drop a part26927 | With the arm stopped, pick up the card and check it. Check the tool is fixed, test the suction on a card again, and restart only with lab staff's approval272628 |
| A joint past its limit, or a poor starting position | Studio shows error code C23: a joint angle exceeds its limit, with the joint and its angle29 | Stop and keep clear1 | The arm started from, or was moved to, a pose outside a joint's range29 | Make sure the path is clear, then press Initial Position in Live Control to bring the arm back303 |
Anything Else
Printed from https://www.anotherplace.com/learn/en/xarm-850/operate/abnormal. Every line cites its source on that page.