Direct Driven Robotic Hand with ESP32, simpleFOC, and SocketCAN
Robotic hands probably hold one of the most complex and challenging design problems in robotics. They need to be lightweight and compact while being able to produce sufficient grasping forces with multi-kinematic chain structures (fingers) with high degrees of freedom (DoF). Popular approaches to robotic hand design have been using servo motors with high gear ratio gearbox with small motors or using linear actuators to address space constraints while meeting grasping force requirements. Combining with mechanism such as cable (tendon) driven or linkage mechanisms, many robotic hands have shown human-like designs with high-DoF. Despite efforts to make highly dexterous robotic hands, simple robotic grippers with 1 or 2 DoF are still popular solution for grasping in robotic manipulation community due to their simplicity and robustness. In fact, many manipulation tasks such as opening a cabinet, grasping a cup, turning a knob of the faucet to get water, etc can be accomplished without having highly dexterous hands. That leads us to a fundamental question: “What are hands for, and how can we design robotic hands to be more effective in manipulation tasks?” Bhatia et al. [1] answers that hands are for interacting with the environment and proposes a new philosophy for robotic hand design which views a robotic hand not only as manipulation tool but also as an agent which can bidirectionally transmit forces and motion signals. The resulting hand design called the Drive Drive Hand (DDHand) priortizing force transparency with 4-DoF have demonstrated capabilites to safetly detect and respond rapidly to variations in the environment. This tells something about the direction of robotic hand design in the future.
[1] Ankit Bhatia, Aaron M Johnson, and Matthew T Mason. Direct Drive Hands: Force-Motion Transparency in Gripper Design. In Robotics: Science and Systems 2019, 2019.