UC San Diego

We present an underwater remote teleoperation robot arm system using a modified hydrostatic rolling diaphragm actuator transmission, the Shallow Water Inspection & Monitoring Robot(SWIMR). This robot arm has 5 degrees of freedom(Dof), corresponding to 5 rolling diaphragm actuator pairs; each uses 2 hydraulic lines, allowing bi-directional motion and force transparency for every joint. Each line has a pressure transducer attached to it, and lines pressures are monitored by the electronics in a sealed oil-filled aluminum box. The box also contains a fluid administration system that automatically pressurizes each line using pressure transducer feedback. The pressurization sequence enables the arm to operate underwater at different depths of up to 100m. The line pressure feedback also allows joint torque calculation, which subsequently enables the calculation of end effector force without employing additional sensors. The remote teleoperation has two modes, one is through button press on a GUI and the other one is through the OMNI haptic pen, while the user observes the arm through camera visual feedback. We have qualitatively assessed the system through underwater teleoperation and force reconstruction tests.