Patent ID: 9204822
Filing Date: 2015-12-08
Classification: A61B,A61N

Abstract:
1. A controller for a functional electrical stimulator for attachment to a leg comprising: a connector for a foot switch for sensing foot rise or foot strike; and a circuit for responding to reduction of resistance of said foot switch when force is applied to the foot switch for generating stimulation pulses; a connector for first and second electrodes for attachment to the leg for supplying stimulation pulses from said circuit, said circuit including a voltage divider of which the foot switch when connected comprises one element, a second element being provided by a digital potentiometer forming part of the controller; and a microcontroller configured to make adaptive adjustment of the resistance of said digital potentiometer to take account of the resistance characteristics of the foot switch to provide an output or reference voltage permitting significant changes in the state of the switch to be monitored, values for parameters of the foot switch varying over time, and a state of the voltage divider being adjustable responsive to variation in values of parameters of the foot switch.