Virtual Interface for an Active Motorized Pedal Exerciser for Human Leg Rehabilitation

Abstract

The ability to move the lower limbs is crucial for most daily activities so there is a permanent need to develop new methods to improve people’s mobility. Common leg rehabilitation devices are pedal exercisers and static bicycles. This paper presents a tool for legs rehabilitation that is based on a motor assisted static bicycle, which is gradually triggered according to the pressure exerted on force sensors located in the pedals. It allows compensation for a leg with mobility limitations permitting the expected cycling movement to be performed easily. This device has also a sensor to monitor the patient’s heart rate. It is used to ensure the treatment’s efficiency and the patient’s safety. Each leg can be trained individually using different parameters. This is particularly useful for stroke patients. If the patient has a leg with mobility problems, the system compensates that leg impairment. The physiotherapist can manage the training parameters (speed, force on each pedal, heart rate) on a computer interface and monitor the training session. There were developed two interfaces for the patient to keep him motivated to stay close to the targeted values. The first interface consists of bar graphs that represent the values of feet forces, speed and heart rate, in real time. The second interface is a virtual game, a bicycle on a road, symbolizing the performance of the user as it would be in real life. The farther the patient’s performance is to the reference values, the fastest he or she will lose points. The game goal is to have the bicycle upright and the road with no inclination. Through ergonomic questionnaires it was determined that the virtual game was the preferred interface.