Kinematics and dynamics identification of a hyper-redundant, electromagnetically actuated manipulator

Abstract

To overcome restrictions of passive, flexible endoscopes in technical tasks (e. g. inspection jobs) as well as in medical interventions, such as minimally invasive surgery, a hyper-redundant active shaft concept is proposed. Due to its unique binary, electromagnetic actuation concept it features good resistance with respect to manipulation forces. Thanks to an active control of each element of the hyper-redundant shaft, different shapes (configurations) can be commanded easily. As a matter of fact, the resulting shape and end effector errors highly depend on the accuracy of the kinematic model. Furthermore, a dynamic model - including a description of the electromagnetic behavior - is required to determine necessary individual poweron durations for the capacity discharge in the tilting circuit of the electromagnetic actuators. In this paper, the dynamics and kinematics for the hyperredundant manipulator are determined. A simplified model for the tilting actuator torque is deduced from the electromagnetic behavior. Subsequently, model parameters are identified and evaluated for a prototypical manipulator based on measurements of the end effector movements.