Design on Articular Motion & Servo Driving with Experimental Analysis for Lower Limb Exoskeleton Robot

doi:10.3901/JME.2019.23.055

Abstract

Abstract: According to the characteristics of human lower limb and requirements of joint motion for level walking, the mechanical structures were designed on exoskeleton robot. The simulation on power of joints during requirements of level walking were analyzed and simulated with ADAMS software, and electro-hydraulic driving was designed on exoskeleton joints for locomotion. A PID control method based on joint error estimation was proposed to meet the requirements of joints assistance and flexibility for human lower limb. The locomotion parameters of joints structure are introduced in detail, for which motion range and driving stroke of the exoskeleton robot are optimized. The kinematics of the robot was analyzed and verified by typical actions of the exoskeleton. The mapping of gait and joint driving in the process of exoskeleton walking is divided, and the PID control with error estimation and compensation are given. From the perspective of joint tracking and power, index parameters of two control methods based on joint error estimation and conventional PID are analyzed and compared quantitatively. Finally, experimental results show that the designed joints and driving system of exoskeleton could have a great affection on power assistant for wearer. Compared with common PID control, the discontinuity of joint driving control output interval is suppressed, the joint tracking error is improved and power walking is much more compliant.

Key words: exoskeleton robot, power assisted control, joint motion, electro-hydraulic driving, error estimation

CLC Number:

TP242

WANG Buyun, WANG Yuepeng, LIANG Yi, WANG Zhihong, JI Jing, XU Dezhang. Design on Articular Motion & Servo Driving with Experimental Analysis for Lower Limb Exoskeleton Robot[J]. Journal of Mechanical Engineering, 2019, 55(23): 55-66.

References

[1] YAN T, CEMPINI M, ODDO C M, et al. Review of assistive strategies in powered lower-limb orthoses and exoskeletons[J]. Robotics and Autonomous Systems, 2015, 64:120-136.
[2] ZOSS A B, KAZEROONI H, CHU A. Biomechanical design of the Berkeley lower extremity exoskeleton (BLEEX)[J]. IEEE/ASME Transactions on Mechatronics, 2006, 11(2):128-138.
[3] HYON S H, HAYASHI T, YAGI A, et al. Design of hybrid drive exoskeleton robot XoR2[C]//2013 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2013:4642-4648.
[4] LI Zhiqiang, XIE Hanxing, LI Weilin, et al. Proceeding of human exoskeleton technology and discussions on future research[J]. Chinese Journal of Mechanical Engineering, 2014, 27(3):437-447.
[5] 范伯骞. 液压驱动下肢外骨骼机器人关键技术研究[D]. 杭州:浙江大学, 2017. FAN Boqian. Research on the key technologies of the hydraulic lower limb exoskeleton robot[D]. Hangzhou:Zhejiang University, 2017.
[6] OUYANG X, DING Shuo, FAN Boqian, et al. Development of a novel compact hydraulic power unit for the exoskeleton robot[J]. Mechatronics, 2016, 38:68-75.
[7] RIENER R,RABUFFETTI M,FRIGO C. Stair ascent and descent at different inclinations[J]. Gait & Posture, 2002, 15(1):32-44.
[8] 陆荣信,陈建芳,冯朝,等. 基于柔性步行路径的双足步行机器人步态参数分析[J]. 中南大学学报, 2014, 45(10):3443-3449. LU Rongxin, CHEN Jianfang, FENG Zhao, et al. Gait parameters analysis of biped walking robot based on flexible walking path[J]. Journal of Central South University, 2014, 45(10):3443-3449.
[9] KIRTLEY C, Hong Kong Polytechnic University. CGA normative gait database, 10 young adults[DB/OL].[2005-04]. http://guardian.curtin.edu.au/cga/data/.
[10] WINTER A, International Society of Biomechanics. Biomechanical data resources, gait data[DB/OL].:[2005-04]. http://www.isbweb.org/data/.
[11] 史小华,王洪波,孙利,等. 外骨骼型下肢康复机器人结构设计与动力学分析[J]. 机械工程学报,2014,50(3):41-48. SHI Xiaohua, WANG Hongbo, SUN Li, et al. Design and dynamic analysis of an exoskeletal lower limbs rehabilitation robot[J]. Journal of Mechanical Engineering, 2014, 50(3):41-48.
[12] LIU Yongjiu, SONG Quanjun, WANG Buyun, et al. Design of a novel gait simulator for rehabilitation training[J]. Sensors & Transducers, 2013, 50(3):90-96.
[13] PAN Dalei, GAO Feng, MIAO Yunjie, et al. Co-simulation research of a novel exoskeleton-human robot system on humanoid gaits with fuzzy-PID/PID algorithms[J]. Advances in Engineering Software, 2015, 79(C):36-46.
[14] 施虎,汪政,何彬,等. 液压式人体行走能量回收装置设计与分析[J]. 机械工程学报, 2018, 54(20):170-179. SHI Hu, WANG Zheng, HE Bin, et al. Design and analysis of mechanical-hydraulic component to harvest energy from human walking[J]. Journal of Mechanical Engineering, 2018, 54(20):170-179.
[15] YI Long, DU Zhijiang, CONG Lin, et al. Active disturbance rejection control based human gait tracking for lower extremity rehabilitation exoskeleton[J]. ISA Transactions, 2017, 67:389-397.
[16] KONG Xiangdong, BA Kaixian, YU Bin, et al. Force control compensation method with variable load stiffness and damping of the hydraulic drive unit force control system[J]. Chinese Journal of Mechanical Engineering, 2016, 29(3):454-464.
[17] YANG Yong, MA Lei, HUANG Deqing. Development and repetitive learning control of lower limb exoskeleton driven by electrohydraulic actuators[J]. IEEE Transactions on Industrial Electronics, 2017, 64(5):4169-4178.
[18] LEE Y, KIM Y J, LEE J, et al. Biomechanical design of a novel flexible exoskeleton for lower extremities[J]. IEEE/ASME Transactions on Mechatronics, 2017, 22(5):2058-2069.
[19] OH S, BAEK E, SONG S, et al. A generalized control framework of assistive controllers and its application to lower limb exoskeletons[J]. Robotics and Autonomous Systems, 2015, 73:68-77.