Prosthetic hands from Touch Bionics

The purpose of this paper is to study the innovative design of prosthetic hands now in production from a Scottish spin‐off company.

The novel features are described, followed by the details of the mechanical construction and the available grip patterns. The benefits of the modular design are explained, and the function and construction of a skin‐like covering are explored. The clinical network supporting the prosthesis is briefly outlined.

The design allows patients to achieve many functional and natural‐looking hand configurations from simple “open” and “close” signals. Miniature motors and gearboxes allow independent movement of each digit, and an integral microprocessor translates electric signals from the forearm to control the movements of the hand. Stall detection ensures that no finger exerts excessive force or wastes power. Artificial skin can be very realistic, with imitation fingernails, hairs and pores. The lifelike prosthesis helps the patient emotionally, socially and at work.

The paper shows how advances in motors, gearboxes, batteries and electronics have enabled a breakthrough in prosthetic design.