Virtual muscles for muscle-like behavior
We have developed a simplified variable admittance controller applied to robot joint control. It is based on a virtual agonist-antagonist mechanism (VAAM) consisting of contractile and parallel elements (CEs and PEs). “Virtual” here means that every joint physically actuated by a standard servo motor can produce variably compliant motions as if it were driven by a pair of agonist and antagonist muscles. The muscles’ parameters for obtaining variable compliance can be adjusted manually and autonomously through sensorimotor learning. For more details, see Xiong et al.,IEEE Transactions on Cybernetics, 2016.