Modeling of Cable-Driven Continuum Robots with Multiple Generally Routed Cables

Cable-driven continuum robots (CCR) are increasingly gaining traction in a wide array of practical applications when compared to their rigid-link counterparts. This paper presents a geometry-based optimization method to model a CCR with multiple generally routed cables. The method discretizes the CCR into equal sections and then assumes imaginary four-bars in each section. The optimization is stated as the minimization of the coupler angles of these four-bars as well as the angles made by tangents. Simulation results are shown for three different cases, which were compared with results obtained from a Cosserat rod model simulation. The maximum RMS error between the two methods is seen to be 1.57 mm (less than 0.88% of the total length of the CCR), which verifies the accuracy of the proposed method. The average simulation time is also significantly faster in the case of the optimization-based method. This method can be used as a quick tool to study CCR’s with diverse cable routings and arrangements.