Most robotics research for dexterous manipulation is based on “serial” actuators: arm-like robots that have a stationary base “shoulder” then a series of arms and elbows out to a gripper at the end. This configuration can reach locations far from the base and provides slow and steady motion, but the entire weight of the arm is supported by the base so it must be geared very heavily. As discussed in previous posts, gears are the enemy of safety and smooth torque control! An alternative approach is the “parallel” robotic arm, where all the heavy actuators are located in the base of the machine, and each controls an arm that reaches out in parallel to the gripper. This means the gripper has little more weight than the payload itself, and can provide very smooth feedback. With our goals at Deft Dynamic’s robotics group Gentle Machine Company to build low-cost tele-operated, parallel machines is a good place to start. Since we are focused on table-top manipulation tasks, a six DoF parallel robot provides a great balance of strength, reach, and sensitive torque feedback for the operator.
Learn more about the technology in Dexapod robots from our published papers at the Gentle Machine Company website.