Energy-Efficient Actuation for Wearable Exoskeletons: A Virtual Prototype

Area of Science:

• Robotics
• Biomechanics
• Mechanical Engineering

Background:

• Assistive wearable exoskeletons require efficient actuation systems to minimize power consumption.
• Optimizing actuation is crucial for extending exoskeleton operational duration and user comfort.

Purpose of the Study:

• To investigate and compare the power consumption of various assistive wearable exoskeleton actuation systems.
• To validate a mathematical model against a virtual experimental framework for analyzing actuation system efficiency.

Main Methods:

• A virtual experimental framework was employed to simulate and analyze different actuation system variants.
• Rigid, series elastic, and parallel elastic actuation systems (single and dual configurations) were evaluated.
• Results were compared against a developed mathematical model.

Main Results:

• A strong correlation was observed between the virtual and mathematical models, indicating high accuracy.
• Combining harmonic drives with belt and pulley mechanisms reduced energy usage.
• The dual variable parallel elastic actuation (VPEA) system with specific joint configurations demonstrated the lowest power consumption.

Conclusions:

• The mathematical model accurately predicts the power consumption of exoskeleton actuation systems.
• The dual VPEA configuration offers significant energy efficiency benefits for exoskeleton design.
• Findings provide guidelines for optimizing actuation systems to improve exoskeleton performance and efficiency.