A Scalable System Model for Discrete Muscle-Like Actuators

A general system modeling and simulation technique is described for discrete muscle-like actuators. These actuators are composed of smaller, modular contractile units connected together, each of which may be controlled individually. Units are activated (recruited) in a manner similar to muscle cell recruitment, whereby the contractions of each individual smaller unit sum to produce a contraction of the entire actuator. Each unit has a lumped-parameter dynamic model, and a mathematical technique is described for automatically constructing a state-space realization of the entire actuator from the individual lumped-parameter models of the units, based on the manner in which they are connected. The method is demonstrated by simulating four different configurations of a particular type of muscle-like actuator driven by the contractions of individual miniature solenoids, demonstrating the flexibility of the approach, and how the system dynamics vary with the activation of the individual units.