Bioinspired Origami Exosuit for Sequential Lifting Assistance with Energy-Aware Compliance and Event-Triggered Impedance
Qunting Yang, Xiaoyu Wu, Bingcong Jian, Haisheng Xia, Zhijun Li
AI summary
Problem
Current back-support exosuits require multiple actuators for multi-joint assistance, increasing weight and complexity while struggling to synchronize with natural human movement rhythms, which compromises comfort and safety.
Approach
The team designed a lightweight exosuit using a deployable Kresling origami structure and a two-stage transmission driven by one motor to sequentially actuate the waist and arms, controlled by an energy-aware compliance and event-triggered impedance framework.
Key results
- Single-motor sequential assistance mechanism mimicking natural load-handling rhythm
- Dual event-triggered impedance control maintaining safe interaction within energy and power thresholds
- Energy-aware compliance strategy enabling passive motion conformity during load lowering
- Up to 22.8% reduction in muscle activation across biceps, triceps, and erector spinae during lifting tasks
Why it matters
Provides a lightweight, low-complexity wearable solution that enhances occupational safety and comfort for manual material handling and rehabilitation applications.
Abstract
Back injuries resulting from manual material handling have long constituted a prominent threat to occu- pational safety. While back-support exosuits offer the potential to augment human strength, their practical implementation is hindered by persistent challenges pertaining to comfort and safety. Drawing inspiration from human biomechanics and muscle behavior, we develop a lightweight assistive exosuit that synchronizes with natural load-handling rhythms. By integrating a deployable Kresling origami structure with a two- stage transmission mechanism, a single motor can sequentially assist both the waist and arms, achieving motion-conforming support with minimal complexity. An energy-aware compliance control strategy allows the system to yield passively during unassisted motion, avoiding interference with voluntary human behavior. We propose an event-triggered impedance control strategy based on an energy tank framework, which adaptively intervenes only when interaction energy exceeds safety thresh- olds. Experimental results demonstrate substantial reductions in muscle activation during load-handling tasks, with decreases of up to 22.8%, 15.4%, and 14.8% in the biceps, triceps, and erector spinae (MV C%), respectively.