Analysis of Fault Types, Causes, and Handling Methods for Industrial Robots
I. Introduction
Industrial robots play a crucial role in modern manufacturing, where their reliable operation directly affects production continuity and product quality. However, faults inevitably occur during long-term operation. Timely and accurate troubleshooting is essential to maintaining stable production. This article comprehensively discusses common fault types, root causes, and corresponding solutions for industrial robots.
II. Types and Symptoms of Industrial Robot Faults
(A) Mechanical Failures
Joint Failure
Symptoms: Unsmooth joint movement, jerking or vibration. For example, a robotic arm’s rotary joint may exhibit noticeable resistance and inaccurate positioning.
Causes: Wear of internal mechanical components, such as damaged bearings or gears, due to prolonged use and friction.
Transmission Failure
Symptoms: Delayed or weak motion, reduced conveyor speed, or material stagnation.
Causes: Loose or slipping belts, stretched/broken chains, or insufficient lubrication.
(B) Electrical Failures
Motor Failure
Symptoms: Motor fails to start or produces abnormal noise (e.g., screeching).
Causes: Short circuits or open circuits in windings, driver failure, or insulation degradation from overheating.
Sensor Failure
Symptoms: Inaccurate feedback from position or vision sensors, leading to poor motion accuracy.
Causes: External interference (e.g., electromagnetic noise, dust), sensor aging, or physical damage.
(C) Software Failures
Program Errors
Symptoms: Unexpected actions, such as grabbing the wrong part or deviating trajectory.
Causes: Logic errors in programming, sudden power loss, or memory overflow.
System Failure
Symptoms: Control system crash, unresponsive interface, or black screen.
Causes: Operating system vulnerabilities, malware infection, or insufficient hardware resources.
III. Root Causes of Industrial Robot Faults
Design Flaws:Poor sealing allowing contamination; suboptimal cable routing causing wear.
Manufacturing Defects:Low machining precision; poor welding or assembly quality.
Environmental Factors:High temperature causing electronic overheating; humidity leading to short circuits; dust and debris affecting sensors and mechanics.
Inadequate Maintenance:Lack of lubrication accelerating wear; infrequent electrical inspections missing early warning signs.
Improper Operation:Failure to follow startup procedures; manual intervention during operation causing damage.
IV. Fault Diagnosis and Troubleshooting Process
(A) Fault Diagnosis
Observe symptoms (motion, error codes, noises).
Consult the maintenance manual for error code interpretation.
Use diagnostic tools (multimeter, oscilloscope) for precise analysis.
(B) Fault Resolution
Mechanical: Replace worn parts (bearings, gears); adjust belt tension; re-lubricate.
Electrical: Repair/replace faulty motors or drivers; clean or replace sensors and recalibrate.
Software: Debug and correct program logic; remove malware; upgrade hardware if needed.
(C) Verification
Restart and test robot operation; recheck parameters (current, voltage, sensor accuracy) to confirm full recovery.
V. Preventive Measures
Design Optimization: Improved sealing, robust cabling, thermal management.
Manufacturing Quality: High-precision machining, automated assembly.
Environmental Control: Climate control, regular cleaning.
Maintenance Plans: Scheduled lubrication, electrical checks.
Operator Training: Comprehensive training on operation, safety, and basic troubleshooting.
VI. Case Studies
(Case 1) Joint bearing wear caused arm vibration and inaccurate picking. Replacing the bearing resolved the issue.
(Case 2) Motor overload due to excessive payload. Reducing load and correcting program settings fixed the fault.
VII. Conclusion
Effective fault management ensures production stability and efficiency. Understanding failure mechanisms, applying proper diagnostics, and implementing preventive strategies enhance robot reliability. Continuous improvements in design, maintenance, and training are key to minimizing downtime and supporting high-quality manufacturing.