Development of a tendon-driven serial manipulator for an aquatic autonomous surface vehicle

This paper proposes a two-degree-of-freedom (2-DOF) tendon-driven manipulator to be attached to an aquatic Autonomous Surface Vehicle ASV (MallARD platform is an example). This attachment will expand the ASV's reachable workspace. It also enables the ASV to perform underwater tasks as well as those performed on the water's surface. The MallARD DOFs are invested in reducing the DOFs of the proposed manipulator. The actuators for the proposed manipulator are installed in the base, above the water line. Wires are used to transmit the power to the manipulator's joints. The proposed wire-driven manipulator can work under high radiation, carry a large payload, and be easily isolated from water. The design of the manipulator is described in detail. The inverse kinematics closed-form solution has been derived analytically. A real-world version of the proposed wire-driven manipulator has been successfully manufactured and tested. The experimental setup is constructed utilizing the proposed manipulator. The experimental results display the feasibility of the proposed tendon-driven serial manipulator. They show that the RMS error between the desired and actual values in each joint is less than $2.1^o$ . Hence, the proposed wire-driven manipulator can be utilized for underwater applications.