Visual Feedback Control of a Rat Ankle Angle Using a Wirelessly Powered Two-Channel Neurostimulator

Area of Science:

• Biomedical Engineering
• Neuroscience
• Rehabilitation Technology

Background:

• Peripheral nerve injuries lead to muscle atrophy and paralysis.
• Functional Electrical Stimulation (FES) is crucial for reinnervating muscles and preventing degeneration.
• Independent stimulation of multiple nerves is required for reconstructing limb function.

Purpose of the Study:

• To develop a wirelessly powered, two-channel neurostimulator for selective FES.
• To apply FES to the peroneal and tibial nerves in a rat model.
• To control rat ankle joint motion using the developed neurostimulator.

Main Methods:

• A wirelessly powered two-channel neurostimulator with a receiver coil connected to rat nerves was designed.
• A low-pass filter detected transmitter signal frequency for nerve stimulation switching.
• A visual feedback system with Proportional Integral (PI) control adjusted stimulation for ankle joint angle control.

Main Results:

• Selective FES was applied to the peroneal and tibial nerves in a rat.
• Dorsal and plantar flexion of the rat ankle joint were selectively induced.
• Rat ankle joint angle was controlled by adjusting stimulation parameters based on visual feedback.

Conclusions:

• A wirelessly powered neurostimulator can selectively stimulate peripheral nerves for FES.
• This technology enables controlled induction of joint movements, like ankle flexion/extension.
• The system shows potential for restoring limb function after nerve damage through precise FES control.