EMG-torque estimation of constant-posture, quasi-constant-torque contractions at varied joint angles

This paper describes an experimental study which relates the simultaneous biceps/triceps surface electromyogram (EMG) of 12 subjects to elbow torque at seven joint angles during constant-posture, quasi-constant-torque contractions. Advanced EMG amplitude (EMGσ) estimation processors were investigated, and an EMG-torque model considering agonist and antagonist co-contractions was evaluated at each joint angle. Preliminary results show that advanced (i.e., whitened, multiple-channel) EMGσ processors lead to improved joint torque estimation and that the EMGσ torque relationship may only change by a scaling factor as a function of joint angle.