FURI | Summer 2021

Designing an Affordable Torsional Spring for a Rotary Series Elastic Actuator

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Rotary Series Elastic Actuators are commonly used in rehabilitation exoskeletons due to their inherent compliance creating a level of safety and comfort. Designing and manufacturing torsional springs for this purpose that can withstand high loads while having a low spring constant is a challenging task. Existing solutions commonly rely on using multiple planar springs in series cut with wire EDM (electric discharge machining) resulting in an expensive and non-adjustable spring pack. This FURI project addresses these issues by exploring a method of manufacturing a torsional spring based on interchangeable wire coil based compression springs.