Interleaved multichannel epimysial stimulation for eliciting smooth contraction of muscle with reduced fatigue

Functional electrical stimulation (FES) refers to the method by which sensory or motor functionality is restored through the use of coordinated stimulation of tissue. Our group has developed a mechanically conformable multielectrode array (cMEA) that can stimulate and record from the surface of muscles with high fidelity and low invasiveness, making the device well suited for various FES applications. The research presented here investigates the feasibility of using a cMEA to deliver asynchronous spatiotemporal stimulation patterns epimysially (on the surface of muscles). Specifically, we employ an interleaved stimulation protocol to achieve force responses with less fatigue and less ripple than those produced by standard simultaneous stimulation protocols delivered at high and low frequencies, respectively. This experimentation demonstrates that asynchronous spatiotemporal stimulation protocols delivered epimysially via a cMEA can improve the characteristics of the resulting force profiles.