Hi-tech trike aids muscle power

A wireless monitoring system developed by a Cambridge engineer will give paraplegics more independence by allowing them to exercise without direct medical supervision.

The system could also be used for close monitoring of kidney and Alzheimer’s patients, to allow them more autonomy and movement in hospital.

Patients with severe physical disabilities must take aerobic exercise to reduce the premature risk of cardiovascular disease. This is achieved by passing electric currents into the limbs to stimulate the muscles to make them move.

At present such exercise takes place indoors under medical supervision as patients must be connected via wires to a machine monitoring their heart rate.

But a Bluetooth-enabled wireless sensor system developed by software engineer Vicky Larmour of Cambridge Consultants should allow patients to exer-cise where and with whom they want, calling for help only if their vital signs become abnormal. Larmour’s solution is based on a tricycle developed at University College, London’s Department of Medical Physics and Bioengineering.

The system normally consists of a pair of ‘electrode trousers’ made of an elastic material containing sensors that are wired up to a small control box attached to a tricycle.

The tricycle’s axle speed and position are relayed to the control box using sensors on the crank and the box, which then calculates the sequence in which the muscles should be stimulated, sending the relevant signals to the electrodes which move the legs in a pedalling motion.

With Larmour’s system, the trouser, tricycle and medical monitoring electrodes can be either individually Bluetooth-enabled or connected via wires to a small multiplexor unit attached to a Bluetooth module.

The data is then forwarded to an intelligent bike-mounted base station that monitors this and issues an alert to the relevant staff using a permanently connected long-range Universal Mobile Telecommunications System (UMTS) connection, when data falls outside a normal range.

Patients can then speak to their specialist via a wireless headset, while streamed video from a bike-mounted camera can also be forwarded to doctors over the UMTS link.

Medics can send back instructions to sensors and other connected devices, while sending help.

‘Over time the base station can build up an intelligent picture of the individual, based on their unique data,’ said Larmour. ‘With the correct sensors the system could also be used for close monitoring of kidney and Alzheimer’s patients, while allowing them more independence and movement in and around a hospital.’