A self-powered and self-sensing knee negative energy harvester

Area of Science:

• Biomechanical Engineering
• Wearable Technology
• Energy Harvesting

Background:

• Wearable devices are crucial for health monitoring and information transmission.
• Developing efficient energy harvesting solutions for these devices is essential.
• Existing methods often lack sufficient power output and stability.

Purpose of the Study:

• To propose the human-friendliness, adaptability, reliability, and economy (HARE) principle for designing human energy harvesters.
• To develop and evaluate a novel biomechanical energy harvester (BMEH) for generating electricity from knee movements.
• To enhance energy conversion efficiency and power output density for stable power generation.

Main Methods:

• Proposed a biomechanical energy harvester (BMEH) mounted on the waist and connected to the ankles.
• Implemented a double-rotor mechanism and a half-wave rectification mechanism to optimize energy conversion.
• Utilized a Gate Recurrent Unit (GRU) deep learning model for excitation mode detection.

Main Results:

• The double-rotor mechanism increased BMEH output power by 70% compared to a single magnet-rotor mechanism.
• Achieved an output power density of 0.07 W/kg at a walking speed of 7 km/h.
• Demonstrated a 99.8% accuracy in excitation mode detection using the GRU model.

Conclusions:

• The proposed BMEH, guided by the HARE principle, offers a significant advancement in wearable energy harvesting.
• The double-rotor mechanism and GRU model integration enhance power generation and system intelligence.
• This technology holds promise for self-powered wearable health monitoring and information transmission systems.