Novel muscle activation sensors for estimating of upper limb motion intention

Measurement of muscle activation is important to understand body motion and the exertion of force. This paper presents two novel muscle activation sensors, a piezo cable muscle activation sensor (pMAS) and an optical muscle activation sensor (oMAS). The pMAS measures variations of a flexible piezo cable band that originate from diameter changes of muscle bundles. The sensors are easily attached and can be worn on clothes. The oMAS, which measures the optical density of muscle fibers, has advantages of small size, ease of use, and non-referenced individual sensing. Muscle activations of the upper limb during movements were collected to evaluate the performance of the proposed pMAS, and oMAS, respectively. Furthermore, the relation between movements and sensor signals was analyzed to estimate the upper limb movements.