Lindhe Xtend is a prosthetics company in Halmstad with the ambition of providing the amputee with functional mobility and a high quality of life. Their main product, the Xtend Foot is a patented prosthetic foot developed to imitate the natural features of the human foot.

Dissatisfaction with prostheses often stems from poor fitting of the part that connects to the body. This often leads to chafing, pistoning and strain. Amongst users of leg prostheses, the strain often results in a reduction of limb volume, further augmenting the bad fit. The development of suspension systems has excelled through the recent years as many prosthetics companies has developed products with integrated vacuum assisted suspension systems, a mounting method where vacuum is used to hold the prosthesis against the body. This mounting mechanism of the limb onto the prosthesis has been proven to prevent fluctuations of limb volume as well as reducing chafing and pistoning.

A vacuum assisted suspension system integrated with the Xtend Foot has been invented using the product development process. The project group has used motion analysis, calculations and concept generation to reach a final concept to be prototyped, called Unify Xtend. Unify Xtend is made to demonstrate the function of the final concept, to actively produce a vacuum during ambulation using a pneumatic actuator.

This project has addressed prosthetics and pneumatics. The project group has, using their knowledge of mechanical engineering and physiology, combined and applied them in this thesis.

Further user testing is needed to evaluate the usability of the prototype, due to reaching target pressure considerably faster than the products of main market competitors.