A Flexible Lower Extremity Exoskeleton Robot with Deep Locomotion Mode Identification

This paper presents a bioinspired lower extremity exoskeleton robot. The proposed exoskeleton robot can be adjusted in structure to meet the wearer’s height of 150–185 cm and has a good gait stability. In the gait control part, a method of identifying different locomotion modes is proposed; five common locomotion modes are considered in this paper, including sitting down, standing up, level-ground walking, ascending stairs, and descending stairs. The identification is depended on angle information of the hip, knee, and ankle joints. A deep locomotion mode identification model (DLMIM) based on long-short term memory (LSTM) architecture is proposed in this paper for exploiting the angle data. We conducted two experiments to verify the effectiveness of the proposed method. Experimental results show that the DLMIM is capable of learning inherent characteristics of joint angles and achieves more accurate identification than the other models. The last experiment demonstrates that the DLMIM can recognize transitions between different locomotion modes in time and the real-time performance varies with each individual.

[1]  Nicola Vitiello,et al.  Gait phase detection based on non-contact capacitive sensing: Preliminary results , 2015, 2015 IEEE International Conference on Rehabilitation Robotics (ICORR).

[2]  Andrea Parri,et al.  A realtime locomotion mode recognition method for an active pelvis orthosis , 2015, 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS).

[3]  R Riener,et al.  Patient-driven control of FES-supported standing up: a simulation study. , 1998, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[4]  Yoshiyuki Sankai,et al.  Human motion oriented control method for humanoid robot , 2002, Proceedings. 11th IEEE International Workshop on Robot and Human Interactive Communication.

[5]  Matthew D. Zeiler ADADELTA: An Adaptive Learning Rate Method , 2012, ArXiv.

[6]  Tingfang Yan,et al.  Review of assistive strategies in powered lower-limb orthoses and exoskeletons , 2015, Robotics Auton. Syst..

[7]  Jun-Young Jung,et al.  A Neural Network-Based Gait Phase Classification Method Using Sensors Equipped on Lower Limb Exoskeleton Robots , 2015, Sensors.

[8]  Weidong Wang,et al.  PSO-SVM-Based Online Locomotion Mode Identification for Rehabilitation Robotic Exoskeletons , 2016, Sensors.

[9]  Baojun Chen,et al.  A Locomotion Intent Prediction System Based on Multi-Sensor Fusion , 2014, Sensors.

[10]  Fan Zhang,et al.  Continuous Locomotion-Mode Identification for Prosthetic Legs Based on Neuromuscular–Mechanical Fusion , 2011, IEEE Transactions on Biomedical Engineering.

[11]  Chee-Meng Chew,et al.  Motion intent recognition for control of a lower extremity assistive device (LEAD) , 2013, 2013 IEEE International Conference on Mechatronics and Automation.

[12]  Xinyu Wu,et al.  Deep rehabilitation gait learning for modeling knee joints of lower-limb exoskeleton , 2016, 2016 IEEE International Conference on Robotics and Biomimetics (ROBIO).

[13]  Long Wang,et al.  A Noncontact Capacitive Sensing System for Recognizing Locomotion Modes of Transtibial Amputees , 2014, IEEE Transactions on Biomedical Engineering.

[14]  Chih-Jen Lin,et al.  LIBSVM: A library for support vector machines , 2011, TIST.

[15]  Deok-Hwan Kim,et al.  Real‐Time Locomotion Mode Recognition Employing Correlation Feature Analysis Using EMG Pattern , 2014 .

[16]  Long Wang,et al.  Fuzzy-Logic-Based Terrain Identification with Multisensor Fusion for Transtibial Amputees , 2015, IEEE/ASME Transactions on Mechatronics.

[17]  Yoshiyuki Sankai,et al.  Humanoid control method based on human knack for human care service , 2002, IEEE International Conference on Systems, Man and Cybernetics.

[18]  Zhaoqin Peng,et al.  Human Moving Pattern Recognition toward Channel Number Reduction Based on Multipressure Sensor Network , 2013, Int. J. Distributed Sens. Networks.

[19]  Yoshiyuki Sankai,et al.  Power assist method based on Phase Sequence and muscle force condition for HAL , 2005, Adv. Robotics.

[20]  Deepak Joshi,et al.  High energy spectrogram with integrated prior knowledge for EMG-based locomotion classification. , 2015, Medical engineering & physics.

[21]  Nicholas P. Fey,et al.  Intent Recognition in a Powered Lower Limb Prosthesis Using Time History Information , 2013, Annals of Biomedical Engineering.

[22]  Robert Riener,et al.  A survey of sensor fusion methods in wearable robotics , 2015, Robotics Auton. Syst..

[23]  Liu De-jun Experimental study on walking gait of normal young people , 2008 .