A compliant parallel mechanism for needle intervention

This paper presents a compliant mechanism for fine motion of a medical robot for needle intervention procedure. The concept of this mechanism is created with the purpose of correcting a needle axis by translating a main robot for needle driving when an unexpected slip happens in needle insertion. In order to specify the concept, a planar compliant mechanism is designed so that the mechanism has maximized workspace for some given design condition. A simplified mathematical model for the designed mechanism is derived and then a pose controller is designed to track a desired trajectory in a plane, which is a similar situation that the compliant mechanism translates a needle driving robot to correct the direction of a needle. The simulation result shows good tracking performance.