Split-Belt Treadmill to Study Reactive Responses to Unexpected Gait Perturbation

The aim is to presents a solution and realization of the design of new split-belt treadmill for controlled, unexpected perturbation during walking to study recovery responses and dynamic stability of the human gait. The construction of the split-belt treadmill consists of several subsystems. The most important subsystems are: actuator, control and sensory subsystem. Actuator subsystem is based on two asynchronous motors, two inverters and two gears (for each belt separately). Control subsystem is made up of Modbus communications between the control computer and two inverters with respect to the parameters of the asynchronous motors. The sensory subsystem is based on the incremental angular speed sensor used to record the behavior of the treadmill belts. The control itself is created through the MatLab software and special custom-made user interface that allows to define a wide range of perturbation schemes. It was then verified whether the belts had the desired speed. Verification of the system has shown that at the recommended speeds of running the belts (at 2.4 km/h), the system is stable, shows no variations in proband load, and real changes in belt velocities are achieved with minimum deviations from the desired values. The main benefit of the described work is the creation of a functional control of the prototype of the treadmill for controlled, mechanical gait perturbations. The split-belt treadmill is designed to study reactive responses during walking that can be further used to fall-risk assessment, clinical or rehabilitation intervention.