Design of a Compliant Robotic Arm Based on Series Elastic Actuator
ZHANG Xiuli1, GU Xiaoxu2, ZHAO Hongfu1, WANG Kun1
1. School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044, China;
2. Beijing A{&E Technologies Co., Ltd., Beijing 100085, China
张秀丽, 谷小旭, 赵洪福, 王昆. 一种基于串联弹性驱动器的柔顺机械臂设计[J]. 机器人, 2016, 38(4): 385-394.DOI: 10.13973/j.cnki.robot.2016.0385.
ZHANG Xiuli, GU Xiaoxu, ZHAO Hongfu, WANG Kun. Design of a Compliant Robotic Arm Based on Series Elastic Actuator. ROBOT, 2016, 38(4): 385-394. DOI: 10.13973/j.cnki.robot.2016.0385.
Abstract:A compliant robotic arm with passive compliant mechanical structure and active compliant control, SoftArm II, is designed to cope with the dynamically-changing work environments and uncertain human-robot interactions. Series elastic actuators (SEA) are introduced between joint motors and links as transmission module, which is composed of linear springs evenly arranged circumferentially. Firstly, the kinematic model, dynamic model and system stiffness model are set up for the compliant 3DOF robotic arm. Then, SEA spring stiffness can be determined using weighted average joint stiffness at several representative poses in the workspace based on the system stiffness model. Position PID (proportional-integral-derivative) control is employed in the robotic arm, while contact forces at the arm's end-point and joint torques are monitored to modify the planned trajectory adaptively. Experiments of the circle trajectory tracking in free workspace, human and the robot pushing along a straight line, and collision imitating, are carried out using the compliant robotic arm SoftArm II. The results show that SoftArm II reaches a good position tracking accuracy in free workspace, compliant interaction between the robotic arm and human is achieved, and collision of the robotic arm is safely avoided. The results indicate that the SEA-based passive compliant mechanical structure and the control approach based on end force and joint torque monitoring have the potential to meet the compliance and safety requirements of a robotic arm used in human-robot coexistence environment.
[1] ABB 推出面向未来的人-机协作产品:YuMi® 双臂机器人[EB/OL]. (2014-09-10) [2015-01-02]. http://www.abb.com. cn/cawp/seitp202/526390b63893568a48257d5f002e76d3.aspx. ABB's human-robot collaborative product for future: YuMi® dual-arm robot. [EB/OL]. (2014-09-10) [2015-01-02]. http://www.abb.com.cn/cawp/seitp202/526390b63893568a48257d5f 002e76d3.aspx.
[2] Albu-Schäffer A, Haddadin S, Ott C, et al. The DLR lightweight robot: Design and control concepts for robots in human environments[J]. Industrial Robot, 2007, 34(5): 376-385.
[3] Borst C, Wimböck T, Schmidt F, et al. Rollin' Justin-Mobile platform with variable base[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA: IEEE, 2009: 1597-1598.
[4] Guizzo E, Ackerman E. How rethink robotics built its new baxter robot worker[EB/OL]. (2012-07-18) [2015-01-02]. http://spectrum.ieee.org/robotics/industrial-robots/rethink-robotics-baxter-robot-factory-worker.
[5] Adee S. Dean Kamen's “Luke Arm” prosthesis readies for clinical trials[EB/OL]. (2008-02-25) [2015-01-02]. http://spectrum. ieee.org/biomedical/bionics/dean-kamens-luke-arm-prosthesis-readies-for-clinical-trials.
[6] Maheu V, Frappier J, Archambault P S, et al. Evaluation of the JACO robotic arm: Clinico-economic study for powered wheelchair users with upper-extremity disabilities[C]//IEEE International Conference on Rehabilitation Robotics. Piscataway, USA: IEEE, 2011: 1-5.
[7] 新松机器人自动化股份有限公司.柔性多关节机器人[EB/OL].(2015-11-06) [2016-03-07]. http://www.siasun. com/product/industrialrobot/product201511 06093319.html. Siasun Robot and Automation Co. Ltd. Compliant multi-joint robot [EB/OL]. (2015-11-06) [2016-03-07]. http://www.siasun.com/product/industrialrobot/product20151106093 319.html.
[8] Klute G K, Czerniecki J M, Hannaford B. Artificial muscles[J]. International Journal of Robotics Research, 2002, 21(4): 295-310.
[9] Narioka K, Hosoda K. Motor development of a pneumatic musculoskeletal infant robot[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA: IEEE, 2011: 963-968.
[10] Raibert M, Blankespoor K, Nelson G, et al. BigDog, the rough-terrain quadruped robot[C]//17th Symposium of the International Federation of Automation Control. Amsterdam, Netherlands: Elsevier, 2008: 10822-10825.
[11] Lens T, von Stryk O. Investigation of safety in human-robot-interaction for a series elastic, tendon-driven robot arm[C] //IEEE/RSJ International Conference on Intelligent Robots and Systems. Piscataway, USA: IEEE, 2012: 4309-4314.
[12] 赵杰,朱延河,臧希喆,等.一种变速比串并联弹性驱动转动关节机构,中国:201310041122.0[P].2013-05-22.Zhao J, Zhu Y H, Zang X Z, et al. A variable reduction ratio serial & parallel elastic rotary joint driving mechanism, China: 201310041122.0[P]. 2013-05-22.
[13] Vu H Q, Marcantini L G. Knee stiffness adjustment for energy efficient locomotion of a legged robot on surfaces with different stiffness[C]//IEEE International Conference on Robotics and Biomimetics. Piscataway, USA: IEEE, 2013: 1825-1831.
[14] Bae J, Kong K. Gait phase-based control for a rotary series elastic actuator assisting the knee joint[J]. Journal of Medical Devices, 2011, 5(3): No.031010.
[15] Kong K, Bae J, Tomizuka M. A compact rotary series elastic actuator for human assistive systems[J]. IEEE/ASME Transactions on Mechatronics, 2012, 17(2): 288-297.
[16] Huang Y, Wang Q N. Torque-stiffness controlled dynamic walking: Analysis of the behaviors of bipeds with both adaptable joint torque and joint stiffness[J]. IEEE Robotics & Automation Magazine, 2016, 23(1): 71-82.
[17] Garcia E, Arevalo J C, Munoz G, et al. Combining series elastic actuation and magneto-rheological damping for the control of agile locomotion[J]. Robotics and Autonomous Systems, 2011, 59(10): 827-839.
[18] Hutter M, Remy C D, Hoepflinger M A, et al. High compliant series elastic actuation for the robotic leg ScarlETH[C]//International Conference on Climbing and Walking Robots. 2011.
[19] 杨智勇,方登建,张静.变刚度柔顺驱动器及其在能量辅助骨骼服中的应用[J].海军航空工程学院学报,2013,28(5):459-465. Yang Z Y, Fang D J, Zhang J. Variable stiffness compliant actuator and its application in energy subsidy exoskeleton suit[J]. Journal of Naval Aeronautical and Astronautical University, 2013, 28(5): 459-465.
[20] 何福本,梁延德,孙捷夫,等.基于 SEA 的机器人仿肌弹性驱动关节研究[J].中国机械工程,2014,25(7):900-905.He F B, Liang Y D, Sun J F, et al. Study on elastically actuated joints of robot for mimicking musculo-tendinous functions based on SEAs[J]. China Mechanical Engineering, 2014, 25(7): 900-905.
[21] Paine N, Oh S, Sentis L. Design and control considerations for high-performance series elastic actuators[J]. IEEE/ASME Transactions on Mechatronics, 2014, 19(3): 1080-1091.
[22] Tsagarakis N G, Laffranchi M. A compact soft actuator unit for small scale human friendly robots[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA: IEEE, 2009: 4356-4362.
[23] Vanderborght B, Albu-Schaeffer A, Bicchi A, et al. Variable impedance actuators: A review[J]. Robotics and Autonomous Systems, 2013, 61(12): 1601-1614.
[24] Hurst J W, Chestnutt J E, Rizzi A A. The actuator with mechanically adjustable series compliance[J]. IEEE Transactions on Robotics, 2010, 26(4): 597-606.
[25] Jafari A, Tsagarakis N G, Sardellitti I, et al. A new actuator with adjustable stiffness based on a variable ratio lever mechanism [J]. IEEE/ASME Transactions on Mechatronics, 2014, 19(1): 55-63.
[26] Jafari A, Tsagarakis N G. A novel actuator with adjustable stiffness (AwAS) [C]//International Conference on Intelligent Robots and Systems. Piscataway, USA: IEEE, 2010: 4201-4206.
[27] Sergi F, Accoto D, Carpino G, et al. Design and characterization of a compact rotary series elastic actuator for knee assistance during overground walking[C]//IEEE RAS and EMBS International Conference on Biomedical Robotics and Biomechatronics. Piscataway, USA: IEEE, 2012: 1931-1936.
[28] dos Santos W M, Caurin G A P, Siqueira A A G. Torque control characterization of a rotary series elastic actuator for knee rehabilitation[C]//IEEE International Conference on Advanced Robotics. Piscataway, USA: IEEE, 2013: 1-6.
[29] Laffranchi M, Chen L, Kashiri N, et al. Development and control of a series elastic actuator equipped with a semi active friction damper for human friendly robots[J]. Robotics and Autonomous Systems, 2014, 62(12): 1827-1836.
[30] Case D, Taheri B, Richer E. Design and characterization of a small-scale magnetorheological damper for tremor suppression[J]. IEEE/ASME Transactions on Mechatronics, 2013, 18(1): 96-103.
[31] Khanicheh A, Mintzopoulos D, Weinberg B, et al. Evaluation of electrorheological fluid dampers for applications at 3-T MRI environment[J]. IEEE/ASME Transactions on Mechatronics, 2008, 13(3): 286-294.
[32] Gan D M, Tsagarakis N G, Dai J S. Stiffness design for a spatial three degrees of freedom serial compliant manipulator based on impact configuration decomposition[J]. Journal of Mechanisms and Robotics, 2013, 5(1): No.011002.
[33] Petit F, Dietrich A, Albu-Schäffer A. Generalizing torque control concepts: Using well-established torque control methods on variable stiffness robots[J]. IEEE Robotics & Automation Magazine, 2015, 22(4): 37-51.
[34] Albu-Schäffer A, Eiberger O, Grebenstein M, et al. Soft robotics-From torque feedback-controlled lightweight robots to intrinsically compliant systems[J]. IEEE Robotics & Automation Magazine, 2008, 15(3): 20-30.
[35] Choi D, Oh J. Development of the Cartesian arm exoskeleton system (CAES) using a 3-axis force/torque sensor[J]. International Journal of Control, Automation and Systems, 2013, 11(5): 976-983.
[36] 朱秋国,熊蓉,吕铖杰,等.新型串联弹性驱动器设计与速度控制[J].电机与控制学报,2015,19(6):83-88.Zhu Q G, Xiong R, Lü C J, et al. Novel series elastic actuator design and velocity control[J]. Electric Machines and Control, 2015, 19(6): 83-88.
[37] 赵洪江.人机工程学[M].北京:高等教育出版社,2006.Zhao H J. Ergonomics[M]. Beijing: Higher Education Press, 2006.