Journal of Bionic Engineering ›› 2024, Vol. 21 ›› Issue (5): 2184-2198.doi: 10.1007/s42235-024-00561-z
A Hierarchical Control Scheme for Active Power‑assist Lower‑limb Exoskeletons
Jing Deng1,2 · Wenzheng Jiang2 · Haibo Gao1 · Yapeng Shi1,3· Mantian Li4
- 1. State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China 2. Shenzhen Academy of Aerospace Technology, Shenzhen 518063, China 3. Faculty of Computing, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China 4. Institute of Intelligent Manufacturing Technology, Shenzhen Polytechnic University, Shenzhen 518055, China
A Hierarchical Control Scheme for Active Power‑assist Lower‑limb Exoskeletons
Jing Deng1,2 · Wenzheng Jiang2 · Haibo Gao1 · Yapeng Shi1,3· Mantian Li4
- 1. State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China 2. Shenzhen Academy of Aerospace Technology, Shenzhen 518063, China 3. Faculty of Computing, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China 4. Institute of Intelligent Manufacturing Technology, Shenzhen Polytechnic University, Shenzhen 518055, China
摘要： Effectively controlling active power-assist lower-limb exoskeletons in a human-in-the-loop manner poses a substantial challenge, demanding an approach that ensures wearer autonomy while seamlessly adapting to diverse wearer needs. This paper introduces a novel hierarchical control scheme comprising five integral components: intention recognition layer, dynamics feedforward layer, force distribution layer, feedback compensation layer, as well as sensors and actuators. The intention recognition layer predicts the wearer’s movement and enables wearer-dominant movement through integrated force and position sensors. The force distribution layer effectively resolves the statically indeterminate problem in the context of double-foot support, showcasing flexible control modes. The dynamics feedforward layer mitigates the effect of the exoskeleton itself on movement. Meanwhile, the feedback compensation layer provides reliable closed-loop control. This approach mitigates abrupt changes in joint torques during frequent transitions between swing and stance phases by decomposed dynamics. Validating this innovative hierarchical control scheme on a hydraulic exoskeleton platform through a series of experiments, the results demonstrate its capability to deliver assistance in various modes such as stepping, squatting, and jumping while adapting seamlessly to different terrains.