High Load-to-Weight Ratio and Large-Deformation Vacuum Pneumatic Actuator

The potential of artificial muscles is becoming increasingly evident in a number of fields, including robotics, prosthetics, and wearable devices. However，there is still a need to develop a soft actuator that is lightweight, compact and has a high load-to-weight ratio.We designed, manufactured, modeled and tested modular contracting actuators which achieves remarkable deformations exceeding 80% while supporting loads up to 4 kg. With a load-to-weight ratio of 455 and an energy conversion efficiency of 20.5% under a 1 kg load. The actuator stands out in performance. It is driven by negative pressure, offering significantly higher safety compared to actuators driven by positive pressure or other methods like electrical, thermal, or chemical means. Our fabrication process is both rapid and cost-effective. Additionally, we present a theoretical model to explain and predict the actuator's motion. Benefiting from its unprecedented modularity and high performance, this actuator is poised for practical applications in fields such as healthcare and industrial production.