Development and Control of a Multifunctional Prosthetic Hand with Shape Memory Alloy Actuators

In this research paper, non-conventional actuation technology, based on shape memory alloys, is employed for the development of an innovative low-cost five-fingered prosthetic hand. By exploiting the unique properties of these alloys, a compact, silent and modular actuation system is implemented and integrated in a lightweight and anthropomorphic rapid-prototyped hand chassis. A tendon-driven underactuated mechanism provides the necessary dexterity while keeping the mechanical and control complexity of the device low. Tactile sensors are integrated in the fingertips improving the overall hand control. Embedded custom-made electronics for hand interfacing and control are also presented and analyzed. For the position control of each digit, a novel resistance feedback control scheme is devised and implemented. The functionality and performance of the developed hand is demonstrated in grasp experiments with common objects.When compared to the current most advanced commercial devices, the technology applied in this prototype provides a series of improvements in terms of size, weight, and noise, which will enable upper limb amputees to carry out their basic daily tasks more comfortably.