Master-Slave Control of the Celiac Minimally Invasive Surgical Robot

A master-slave control algorithm is proposed to improve the hand-eye coordination for an endoscopic celiac minimally invasive surgical robotic system based on the endoscopes. Forward and inverse kinematic models of the slave hand system are established based on the screw theory. Then a master-slave motion control algorithm is proposed based on the kinematic models in the endoscope coordinates, which consists of the motion consistency control, the relative motion control and the proportional motion control. Because the wrist of the master hand is passive (not driven by motor), it can't remain stationary at any position, and therefore the postures of the master and slave manipulators can't keep the same at the beginning of the operation, at the interruption in the middle of the operation, or at the adjustment of the workspace of the master. For this reason, three auxiliary functions are implemented, which are the master-slave posture registration function, the replacement function of surgical instrument and the master-salve remapping function. Last but not least, the collaring and the threading experiments are carried out. The maximum space position errors of these two groups of experiments are less than 1 mm, which shows the algorithm can effectively improve the consistency of hand-eye coordination.