A Versatile Pneumatic Actuator Based on Scissor Mechanisms: Design, Modeling, and Experiments

A new versatile pneumatic actuator called a scissor-mechanism-based vacuum powered artificial muscle (SMVAM) is proposed in this letter. The actuator is composed of a soft airtight skin and a scissor structural skeleton, and based on the types of scissor units in the skeleton, the actuator can be designed into linear or curvilinear types. The principal motion of the actuator is the contraction process driven by negative pressure to generate a large force and considerable contraction ratio, and the extension process of the actuator driven by positive pressure is the restoration motion of the actuator. The design method for SMVAMs and a quasi-static model to estimate the blocked force of the actuators are developed. Based on the experimental results, the actuators can generate a maximum contraction ratio of 80% and a large force of approximately 300 N in the vertical direction and can also achieve contraction and extension routines in a nonvertical manner with a tip payload. Furthermore, the case study has shown the promise of the actuator for different applications.