A Compact Cardiopulmonary Resuscitation Chest Compression Device Using a Torsion-Based Series Elastic Actuator

Cardiopulmonary Resuscitation (CPR) is crucial in emergency cardiac arrest situations. To reduce paramedic fatigue and ensure steady CPR performance, automated chest compression devices have been developed. However, current devices do not consider the patient’s chest condition, potentially increasing the risk of rib fractures and reducing cardiac output. This paper proposes a chest compression device using a linear series elastic actuator (SEA) for CPR. The SEA can compress and measure force simultaneously, adjusting compliance based on the spring’s stiffness. Unlike other SEAs that use compression springs, this design employs a torsion spring. The mechanism and the working principle of the linear SEA are presented, along with an analysis of the custom torsion spring. Experiments on a test bench validate the spring’s stiffness and assess the device’s performance. Additional experiments with a CPR training manikin demonstrate the device’s suitability for compression depth tracking and force control. The proposed design is space-efficient and offers accurate compression force sensing, providing a promising solution for effective CPR in emergencies.