Force estimation using an approximately physiological mechanism

Force estimation is important in biomechanical studies to extract the motion intent. The amplitude of the surface electromyogram (SEMG) was used to estimate the muscle force without a force sensor. Mean absolute value (MAV) has been widely used for amplitude estimation of the SEMG due to the probabilistic nature of SEMG, but it has no comprehensive physiological justification. We proposed the force estimation method inspired from a physiological mechanism which explains the relationship between SEMG and muscle force. The mechanical muscle model was estimated based on the extracted information during the index finger isometric contraction. The estimation performances (R²) of the force were evaluated with three subjects (0.79 ± 0.04). The proposed method could be widely applicable to quantitatively analyze muscle activities by SEMG.