Mode switching control methods for man-machine collaborated robotic systems

In the industrial world, not only autonomous machinery as industrial robots but also man-machine cooperative systems as power-assist systems have attracted special interest recently. Kondo, et al. proposed the scheme of man-machine collaborated systems (MMCSs) called "Kyodo" and its application to some assembling robot. In the MMCSs, efficient mode switching between human-oriented task and machine-oriented task is important. However, its issue has not been fully addressed yet. This study discusses mode switching control methods for the MMCSs. Especially, we treat the following two cases for a simple robotic system. The first case is the switching from a power-assist mode (PAM) to an automatic positioning mode (APM). The other one is the switching from an automatic traveling mode (ATM) to PAM. To obtain a smooth switching, this study utilizes a two-degree-of-freedom control system structure which consists of an online impedance control simulator and an LQI servo controller. No input saturation and/or stopping appear at the switchings in these methods. The effectiveness of the methods is verified experimentally.