Inverse Kinematics Analysis and COG Trajectory Planning Algorithms for Stable Walking of a Quadruped Robot with Redundant DOFs
- 157 Downloads
This paper presents a new Center of Gravity (COG) trajectory planning algorithm for a quadruped robot with redundant Degrees of Freedom (DOFs). Each leg has 7 DOFs, which allow the robot to exploit its kinematic redundancy for various locomotion and manipulation tasks. Also, the robot can suitably adapt to different environment (e.g., passing through a narrow gap) by simply changing the body posture. However, the robot has significant COG movement during the leg swinging phase due to the heavy leg weights; the weight of all the four legs takes up 80% of the robot’s total weight. To achieve stable walking in the presence of undesired COG movements, a new COG trajectory planning algorithm was proposed by using a combined Jacobian of COG and centroid of a support polygon including a foot contact constraint. Additionally, the inverse kinematics of each leg was solved by modified improved Jacobian pseudoinverse (mIJP) algorithm. The mIJP algorithm could generate desired trajectories for the joints even when the robot’s leg is in a singular posture. Owing to these proposed methods, the robot was able to perform various modes of locomotion both in simulations and experiments with improved stability.
Keywordslegged robot redundant degree-of-freedoms stable walking center-of-gravity planning
Unable to display preview. Download preview PDF.
This work was supported by the 2018 Research Fund (1.180015.01) of UNIST (Ulsan National Institute of Science and Technology), the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (No. NRF-2015R1C1A1A01053763), and the NRF Grant funded by the Korean Government (MSIT) (No. NRF-2016R1A5A1938472).
- Kwak B, Park H, Bae J. Development of a quadruped robot with redundant DOFs for high-degree of functionality and adaptation. Proceedings of IEEE International Conference on Advanced Intelligent Mechatronics (AIM), Banff, Canada, 2016, 608–613.Google Scholar
- Shkolnik A, Tedrake R. Inverse kinematics for a point-foot quadruped robot with dynamic redundancy resolution. Proceedings of IEEE International Conference on Robotics and Automation (ICRA), Rome, Italy, 2007, 4331–4336.Google Scholar
- Byl K, Byl M, Satzinger B. Algorithmic optimization of inverse kinematics tables for high degree-of-freedom limbs. Proceedings of ASME Dynamic Systems and Control Conference (DSCC), San Antonio, USA, 2014.Google Scholar
- Byl K, Byl M. Design of fast walking with one-versus two-at-a-time swing leg motions for RoboSimian. Proceedings of IEEE International Conference on Technologies for Practical Robot Applications (TePRA), Woburn, USA, 2015, 1–7.Google Scholar
- Siciliano B, Slotine J-J E. A general framework for managing multiple tasks in highly redundant robotic systems. Proceedings of International Conference on Advanced Robotics, Pisa, Italy, 1991, 1211–1216.Google Scholar
- Cheng F T, Lee H L, Orin D E. Increasing the locomotive stability margin of multilegged vehicles. Proceedings of IEEE International Conference on Robotics and Automation (ICRA), Detroit, USA, 1999, 1708–1714.Google Scholar
- Pongas D, Mistry M, Schaal S. A robust quadruped walking gait for traversing rough terrain. Proceedings of IEEE International Conference on Robotics and Automation (ICRA), Roma, Italy, 2007, 1474–1479.Google Scholar
- ROBOTIS Dynamixel, [2018-03-13], http://www.robotis.com/.
- SMOOTH-ON Dragon skin, [2018-03-13], https://www.smooth-on.com/product-line/dragon-skin/.
- MathWorks MATLAB, [2018-03-01], https://www.mathworks.com/.
- Coppelia Robotics V-REP, [2018-03-01], http://www.coppeliarobotics.com/.
- Hirose S, Tsukagoshi H, Yoneda K. Normalized energy stability margin and its contour of walking vehicles on rough terrain. Proceedings of IEEE International Conference on Robotics and Automation (ICRA), Seoul, Korea, 2001, 181–186.Google Scholar