Abstract：An elephant-trunk-like robot arm actuated by shape memory alloy (SMA) is proposed, which consists of some 2-DOF (degree of freedom) soft modules in series. The proposed robot arm shows the merits of light weight, compact structure and flexible motion. The kinematics models of the soft module and the robot arm with several soft modules in series are analyzed. For the soft module, the open-loop control experiment is carried out to verify the reliability of the kinematic model, and the closed-loop control experiment is carried out to verify the feasibility of the closed-loop control.
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