Hoist-Based Shape Memory Alloy Actuator with Multiple Wires for High-Displacement Applications

Shape memory alloys (SMAs) are smart materials that change their crystalline structures when subjected to heat or tension, resulting in a macroscopic deformation. When applied actuators, SMAs present remarkable load–weight ratio and flexibility, making them suitable for diverse applications. However, challenges such as energy consumption, nonlinear control, low displacement must be considered. This paper presents new strategy improving the total while adding neither supplementary SMA wires nor complex external devices. In addition, novel control is proposed improve nonlinearity of SMAs’ behavior. A hoist system was developed linearly increase with number pulleys wire turns used. The design also used parallel actuation load capacity. actuator presented high capacity reduced weight, lifting more than 100 times its own mass, low-cost robust system. simplicity actuator’s production lightness make it option wide range applications, including wearable exoskeletons.