Human-machine interaction force control: using a model-referenced adaptive impedance device to control an index finger exoskeleton
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Exoskeleton robots and their control methods have been extensively developed to aid post-stroke rehabilitation. Most of the existing methods using linear controllers are designed for position control and are not suitable for human-machine interaction (HMI) force control, as the interaction system between the human body and exoskeleton is uncertain and nonlinear. We present an approach for HMI force control via model reference adaptive impedance control (MRAIC) to solve this problem in case of index finger exoskeleton control. First, a dynamic HMI model, which is based on a position control inner loop, is formulated. Second, the theoretical MRAC framework is implemented in the control system. Then, the adaptive controllers are designed according to the Lyapunov stability theory. To verify the performance of the proposed method, we compare it with a proportional-integral-derivative (PID) method in the time domain with real experiments and in the frequency domain with simulations. The results illustrate the effectiveness and robustness of the proposed method in solving the nonlinear HMI force control problem in hand exoskeleton.
Key wordsInteraction force Adaptive control Exoskeleton Human-machine interaction (HMI) Impedance
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- Bi, Q., Yang, C.J., Deng, X.L., et al., 2013. Contacting mechanical impedance of human finger based on uncertain system. IEEE/ASME Int. Conf. on Advanced Intelligent Mechatronics, p.1619–1624. [doi:10.1109/AIM.2013.6584328]Google Scholar
- Fang, H.G., Xie, Z.W., Liu, H., et al., 2009. An exoskeleton force feedback master finger distinguishing contact and non-contact mode. IEEE/ASME Int. Conf. on Advanced Intelligent Mechatronics, p.1059–1064. [doi:10.1109/AIM.2009.5229726]Google Scholar
- Huo, W.G., Huang, J., Wang, Y.J., et al., 2011. Control of upper-limb power-assist exoskeleton based on motion intention recognition. Int. Conf. on Robotics and Automation, p.2243–2248. [doi:10.1109/ICRA.2011.5980483]Google Scholar
- Nakagawara, S., Kajimoto, H., Kawakami, N., et al., 2005. An encounter-type multi-fingered master hand using circuitous joints. Proc. IEEE Int. Conf. on Robotics and Automation, p.2667–2672. [doi:10.1109/ROBOT.2005.1570516]Google Scholar
- Pang, Z.H., Chui, H., 2009. System Identification and Adaptive Control. Beijing University of Aeronautics and Astronautics Press, Beijing, p.78–80 (in Chinese).Google Scholar
- Polotto, A., Modulo, F., Flumian, F., et al., 2012. Index finger rehabilitation/assistive device. 4th IEEE RAS/EMBS Int. Conf. on Biomedical Robotics and Biomechatronics, p.1518–1523. [doi:10.1109/BioRob.2012.6290676]Google Scholar
- Wege, A., Kondak, K., Hommel, G., 2006. Force control strategy or a hand exoskeleton based on sliding mode position control. Proc. IEEE/RSJ Int. Conf. on Intelligent Robots and Systems, p.4615–4620. [doi:10.1109/IROS.2006.282169]Google Scholar