Dynamic electrode force control of resistance spot welding robot

Abstract

Although there has been always existing a strong desire to apply adjustable dynamic electrode force in resistance spot welding (RSW) over decades, technical limitation laid a barrier to its implementation and application. However, with the introduction of servo motor control technology into spot welding gun, this issue will not stay unsolvable any more. After a brief introduction of RSW process and currently adopted electrode force control method, this paper presents two potential solutions, with which using dynamic electrode force to achieve preferable weld quality becomes realizable. Experiment results indicate that, supported by advanced motion control technology of ABB industrial robot, dynamic force profile with fast response and high accuracy is achieved, which will fully meet the critical requirements of spot welding process.