Developing a body-centric wireless network solution for systems used to correct movement disorder caused by paralysis
Start date: 20 April 2009
Each year, more than 140,000 cases of stroke are registered in the UK. Of all acute stroke patients, half will be left with impaired use of their limbs. Functional Electrical Stimulation (FES) techniques are well established for improving mobility, function and quality of life of the neurological injured person. Control of FES is usually achieved using body worn pressure sensors, accelerometers or electromyogram sensors. Depending on the extent of the injury and complexity of movement disorder, many sensors and channels of stimulation might be necessary to improve gait or movement. However, this results in a complex multi-channel stimulator which is often rejected by the user due to the size, complexity and cosmesis. These issues can be addressed to some extent by using distributed systems that split the complex function of the multi-channel stimulator into multiple local stimulators around the body. However using conventional techniques this results in a complex network of wires, making it complex and inconvenient for the wearer. The obvious solution is to replace the wires with a wireless network of sensors and stimulators where each node from the network communicates with one or multiple other nodes and small enough to be placed where it needed. Because of the safety implications of this application, any body-centric wireless network of this type must be at least as reliable as a wired system with acceptable latencies. Our research involves choosing the wireless technology that can ensure reliability, short latency and low power consumption in all environments, and investigating the most efficient network topology that performs the best for this application. The work also involves tests on the propagation of waves around the body and antenna performance in different locations. Designing the wireless network with the appropriate characteristics will allow the development of a new generation of FES system that are very convenient for use and expandable so that new sensors or stimulators can be easily added to the network to meet the needs of each individual user.
Choukri A Mecheraoui, Stacey Finn, Rod Lane, Dr Jon Cobb, Prof Ian Swain