Design of a Remote Center-of-Motion Parallel Mechanism for Percutaneous Interventions

Abstract Percutaneous intervention procedures require the insertion and manipulation of a puncture instrument within the patient's body. In this context, a Remote Center-of-Motion (RCM) parallel mechanism, thermed PercuCob-RCM, is designed to support clinicians during needle-based interventions by securely holding the puncture in-strument and enabling a translational motion along the direction of the needle and rotational motions about a fixed insertion point. A key challenge in developing this mechanism lies in the actuation of its universal joint. This work investigates three alternative actuation schemes and evaluates them to guide the construction of a suitable prototype. The prototype design is formulated as a bi-objective optimization problem. The first objective function represents the overall size of the mechanism, while the second captures the motor torques required to sustain a specified axial tool force. For each actuation scheme, the set of non-dominated Pareto-optimal solutions is computed and analyzed. Based on the comparative assessmentoftheParetofronts, apreferreddesignconfiguration is selected, and a functional prototype is developed.