Adaptive region control for robotic soldering of flexible PCBs

While robot manipulators have been widely applied in manufacturing and industry, most applications are limited to rigid objects. Increasing demands for manipulating soft objects have been reflected in the emerging 3C manufacturing, such as the soldering of flexible PCBs. Because of the property of deformation, soldering the flexible PCB cannot be performed with conventional robotic manipulation techniques. In this paper, an adaptive region controller is proposed to deal with the deformation of flexible PCBs, where the control objective is specified as a region attached to the flexible PCB. The proposed controller enables an additional assistive arm to reach the region and contact and fix the PCB, which thus eliminates the deformation. A coordination scheme is also developed to activate the soldering end effector after the deformation is stabilized. The stability of the closed-loop system is rigorously proved with Lyapunov methods, and experimental results are presented to illustrate the performance of the proposed controller.