Abstract
In this study group, we are developing an autonomous dual-arm robot for the complex work which involves autonomous cooperation of two arms. One of the complex works that requires human-like skills is to draw the characters with a pen that one hand grips on the clipboard that the other hand grasps. However, it is important to prevent one arm being damaged by the force that the other arm added on this work. On the other hand, it requires considering the stiffness of two arms and controlled objects while a robot draws a character because those stiffness depend on contact point of two arms, shapes of controlled objects and how to grasp a pen and a clipboard. Therefore, we implemented impedance control to change the parameters depending on the stiffness of controlled object on each arm of dual-arm robot. And this paper suggests the method to decide the impedance parameters of two arms for cooperative motion based on the model that how a clipboard is transformed and the relational expression of the force that two arms added. As the results of experiment that dual-arm robot draws a line and a circle, the control suggested in this study is proved to be effective.
