For a number of years we have been working on methods to characterise the behaviour of prosthetic feet (1, 2), allowing us to identify one of the key problems with passive devices, their inability to provide the positive work seen at the anatomical ankle at push-off (3). This work formed the background to an EPSRC project led by Professor David Howard in which we further developed our analysis methods (4) and demonstrated the potential for hydraulic technology to enable controlled storage, transfer between joints, and return of energy in lower limb prostheses (5). Our results have encouraged us to pursue further work in this area and we are also exploring exploitation routes.
Rig for characterisation of amputee independent prosthesis properties (AIPP).
We are taking a similar approach to the design and development of new upper limb prosthetic devices, focusing first on better understanding the problems with myoelectric prostheses. John Head’s PhD thesis investigated the role that poor socket fit can play in determining functional capability (6) and this work has been extended in Alix Chadwell’s PhD work (7).
Reaction time experimental setup used in Chadwell’s PhD.
Our group has a long standing interest in the design and development of improved functional electrical stimulation systems. The work dates back to the late 1990s when Professor Laurence Kenney worked in the Netherlands on the development and evaluation of an implantable drop foot stimulator (8), later commercialised under the trade name StimUStep. Since then we have worked on two projects to develop new FES systems. In the first project we worked with the Sheffield team, led by Professor Tony Barker and Dr Ben Heller, on the design of an array-based stimulator with automated setup for dropfoot correction (9), believed to be the world’s first CE marked system of its kind. The first ever take-home study of such a device was led by our group (10) and showed that the technology can be used by patients without technical support. More recently we have been working with Odstock Medical to develop an upper limb functional electrical stimulation system to enable FES-supported functional task practice (11). Through a series of NIHR-funded projects we have progressed to the stage of a regulatory-approved trial of the system.
Upper limb FES system developed by in a collaboration between our group and Odstock Medical.
This area of interest builds on the expertise of our newest member, Dr Gouwu Wei. His background is in advanced robotics and he applies state-of-the-art kinematics to the analysis and synthesis of human movement. He is working to design and develop affordable institutional/domestic assistive robots and rehabilitation devices based on the concept of reconfigurability.