Design Considerations of Foot-Pedal Switch Controller to Reduce Muscle-Fatigue in Industrial Workers

Although Industrial Automation has gained sufficient expanse in machining works, the medium and small-scale industries still rely on manual and semi-automated processes. In multi-functional machines like Sewing Machines, Lathes, Press use of Foot-pedal switches is very common. Repeated cycles of work cause muscular fatigue. This paper aims at analyzing the operation and gain insights on fatigue patterns in such work conditions. The entire pedal operation is broken into two cycles being lifting and pressing-returning. sEMG technique is used to identify the muscle activity in three muscles namely Gastrocnemius (GA), Soleus(S), Tibialis Anterior (TA). Strain-gauge based load cells are employed on the foot-pedal to understand the Force-sEMG relation. Time-domain and Frequency domain parameters are evaluated for fatigue conditions. We observed that the RMS and MAV values were increasing and MNF and MDF values had negative gradient, which confirms fatiguing in all the three muscles. The MNP of TA was 12.6% of GA and S muscles during fast motions and 52.2% and 11.5% during pressing motion.