Quasi-Passive Shoulder Exoskeleton

Human walking gait is touted to be the most efficient biped walking gait. With necessity and purpose determining the varied types of gait that we follow during locomotion, one major factor that controls or differentiates human gaits is Arm Swing. Earlier studies proved that there is 7% reduction in the metabolic cost due to the arm swing. However, when army soldiers carry their weapon from one place to another, people who look for rehabilitation of their normal gait after an accident and arm amputees consume more energy during walking. The primary goal of the project is to determine which type of gait caused by arm swing requires high metabolic cost and the secondary goal was to look out for ways to reduce the metabolic cost by providing alternate ways for the arm swing if it is required. 

A group of 6 subjects was asked to walk in four different gaits on a treadmill to record and analyze their oxygen levels. The goal was to enable subjects to walk with a custom designed upper body exoskeleton. Accordingly, a quasi-passive exoskeleton which suits all human bodies was designed and 3D printed to perform experiments to test the reduction of metabolic cost in folded arm walking gait. The empirical results from the tests validate a 10% reduction in the metabolic cost of walking aided by the use of the exoskeleton designed.