Path Following Method for Snake Robot Based on the Angle Symmetry Adjustment
ZHANG Danfeng1, LI Bin2,3, CHANG Jian2,3
1. School of Information and Control Engineering, Liaoning Shihua University, Fushun 113001, China;
2. State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China;
3. Institutes for Robotics and Intelligent Manufacturing, Chinese Academy of Sciences, Shenyang 110169, China
Abstract:In order to control the snake robot to follow desired paths on the ground with unknown friction coefficients, a path following method is proposed based on the angle symmetry adjustment. According to the kinematics analysis, if the joint angle changes symmetrically, the locomotion direction of the robot doesn't change. Otherwise, the locomotion direction will change. Based on this idea, a parameter is set in the torque control, and it can adjust the angle symmetry which is regulated by the positions of the target point and the robot. The target point is set on the desired path, and it is constantly updated along the desired path as the robot is moving. When the robot does not move along the desired path, the direction parameter changes asymmetrically. Negative feedback control is used to decrease the degree of asymmetry until it vanishes, so that the robot moves along the desired path again. Finally simulations on different grounds with unknown friction coefficient are carried out, and the trajectories and the errors obtained show that the robot locomotion direction can be adjusted according to the desired path. The proposed method can not only control the snake robot to follow the desired straight and curve paths on different grounds with unknown friction coefficient, but also complete the path following task when side slip occurs.
[1] Zhang A F, Ma S G, Li B, et al. Adaptive controller design for underwater snake robot with unmatched uncertainties[J]. Science China Information Sciences, 2016, 59(5):1-15.
[2] Malayjerdi M, Akbarzadeh A.Analytical modeling of a 3-D snake robot based on sidewinding locomotion[J].International Journal of Dynamics and Control, 2017, 7(1):83-93.
[3] 郭宪,王明辉,李斌,等.基于最小无穷范数的蛇形机器人最优力矩控制[J].机器人,2014,36(1):8-12.Guo X, Wang M H, Li B, et al. Optimal torque control of a snake-like robot based on the minimum infinity norm[J]. Robot, 2014, 36(1):8-12.
[4] 叶长龙.蛇形机器人的机构设计和运动控制[D].沈阳:中国科学院沈阳自动化研究所,2004.Ye C L. Mechanism design and locomotion control of snake-like robots[D]. Shenyang:Shenyang Institute of Automation, Chinese Academy of Science, 2004.
[5] Wu X D, Ma S G. Sensor-driven neural controller for self-adaptive collision-free behavior of a snake-like robot[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA:IEEE, 2011:191-196.
[6] Liljeback P, Pettersen K Y. Waypoint guidance control of snake robots[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA:IEEE, 2011:937-944.
[7] Liljeback P, Haugstuen I U, Pettersen K Y. Path following control of planar snake robots using a cascaded approach[J]. IEEE Transactions on Control Systems Technology, 2012, 20(1):111-126.
[8] Rezapour E, Liljeback P. Path following control of a planarsnake robot with an exponentially stabilizing joint control law[J]. IFAC Proceedings Volumes, 2013, 46(10):28-35.
[9] Hasanabadi E, Mahjoob M J. Trajectory tracking of a planarsnake robot using camera feedback[C]//2nd International Conference on Control, Instrumentation and Automation. Piscataway, USA:IEEE, 2011:894-897.
[10] Matsuno F, Sato H. Trajectory tracking control of snake robotsbased on dynamic model[C]//IEEE International Conference on Robotics and Automation. Piscataway, USA:IEEE, 2005:3029-3034.
[11] Mohammadi A, Rezapour E, Maggiore M, et al. Maneuvering control of planar snake robots using virtual holonomic constraints[J]. IEEE Transactions on Control Systems Technology, 2016, 24(3):884-899.
[12] Ariizumi R, Takahashi R, Tanaka M, et al. Head-trajectorytracking control of a snake robot and its robustness under actuator failure[J]. IEEE Transactions on Control Systems Technology, 2018. DOI:10.1109/TCST.2018.2866964.
[13] Ma S G, Tadokoro N. Analysis of creeping locomotion of a snake-like robot[J]. Autonomous Robots, 2006, 20(1):15-23.
[14] 张丹凤,吴成东,李斌,等.基于能量平衡的蛇形机器人被动蜿蜒控制方法[J].科学通报,2013,58(S2):83-90. Zhang D F, Wu C D, Li B, et al. Passive creeping based on energy balance of a snake-like robot[J]. Chinese Science Bulletin, 2013, 58(S2):83-90.
[15] 王智锋,马书根,李斌,等.基于能量的蛇形机器人蜿蜒运动控制方法的仿真与实验研究[J].自动化学报,2011,37(5):604-614. Wang Z F, Ma S G, Li B, et al. Simulation and experimental study of an energy-based control method for the serpentine locomotion of a snake-like robot[J]. Acta Automatica Sinica, 2011, 37(5):604-614.