Abstract：A novel triangle-type remote centre motion (RCM) mechanism is proposed to be applied to minimally invasive surgery due to its simple structure and high stiffness. In order to obtain outstanding performance, a new multi-objective optimization model is presented, which consists of four objectives: a global kinematic index, a mechanical compactness index, a global comprehensive stiffness index, and a global dynamic index; three constraints: workspace, mechanical parameters, and mass; two design variables: two angles between two adjacent joints. The non-dominated sorting genetic algorithm-II (NSGA-II) is adopted to solve multi-objective optimization problems. The prototype of the triangle-type RCM mechanism is set up based on the optimization results. The effectiveness of the triangle-type RCM mechanism is validated by an experiment.
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