[1] P Fankhauser, M Hutter. Anymal: A unique quadruped robot conquering harsh environments. Research Features, 2018, 126: 54-57.
[2] J Hooks, M S Ahn, J Yu, et al. ALPHRED: A multi-modal operations quadruped robot for package delivery applications. IEEE Robotics and Automation Letters, 2020, 5(4): 5409-5416.
[3] D Kim, D Carballo, J D Carlo, et al. Vision aided dynamic exploration of unstructured terrain with a small-scale quadruped robot. 2020 IEEE International Conference on Robotics and Automation (ICRA), Paris, France, September 15, 2020: 2464-2470.
[4] R B McGhee, A A Frank. On the stability properties of quadruped creeping gaits. Mathematical Biosciences, 1968, 3: 331-351.
[5] H Park, B Kwak, J Bae. Inverse kinematics analysis and COG trajectory planning algorithms for stable walking of a quadruped robot with redundant DOFs. Journal of Bionic Engineering, 2018, 15(4): 610-622.
[6] G Bledt, M J Powell, B Katz, et al. MIT Cheetah 3: Design and control of a robust, dynamic quadruped robot. 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Madrid, Spain, October 1-5, 2018: 2245-2252.
[7] Y Zhao, X Chai, F Gao, et al. Obstacle avoidance and motion planning scheme for a hexapod robot Octopus-Ⅲ. Robotics and Autonomous Systems, 2018, 103: 199-212.
[8] L H Mao, Y Tian, F Gao, et al. Novel method of gait switching in six-legged robot walking on continuous-nondifferentiable terrain by utilizing stability and interference criteria. Science China Technological Sciences, 2020, 63(12): 2527-2540.
[9] G Figliolini, M Ceccarelli. Easy programming of an electropneumatic walking robot. IFAC Proceedings Volumes, 1997, 30(20): 747-754.
[10] G Figliolini, M Ceccarelli. Walking programming for an electropneumatic biped robot. Mechatronics, 1999, 9(8): 941-964.
[11] M Wang, M Wonsick, X Long, et al. In-situ terrain classification and estimation for NASA's humanoid robot valkyrie. 2020 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM), Boston, MA, USA, July 6-9, 2020: 765-770.
[12] Y de Viragh, M Bjelonic, C D Bellicoso, et al. Trajectory optimization for wheeled-legged quadrupedal robots using linearized zmp constraints. IEEE Robotics and Automation Letters, 2019, 4(2): 1633-1640.
[13] T Yamamoto, T Sugihara. Foot-guided control of a biped robot through ZMP manipulation. Advanced Robotics, 2020, 34(21-22): 1472-1489.
[14] T Ando, T Watari, R Kikuuwe. Reference ZMP generation for teleoperated bipedal robots walking on non-flat terrains. 2021 IEEE/SICE International Symposium on System Integration (SII), Iwaki, Fukushima, Japan, January 11-14, 2021: 794-800.
[15] P Biswal, P K Mohanty. Development of quadruped walking robots: A review. Ain Shams Engineering Journal, 2021, 12(2): 2017-2031.
[16] J Dai, J J Rees. Mobility in metamorphic mechanisms of foldable/erectable kinds. Proceedings of 25th ASME Biennial Mechanisms and Robotics Conference, 1998: 375-382.
[17] K Xu, X Ding. Gait analysis of a radial symmetrical hexapod robot based on parallel mechanisms. Chinese Journal of Mechanical Engineering, 2014, 27(5): 867-879.
[18] K Xu, P J Zi, X L Ding, Gait analysis of quadruped robot using the equivalent mechanism concept based on metamorphosis. Chinese Journal of Mechanical Engineering, 2019, 32: 8.
[19] C Liang, M Ceccarelli. Design and simulation of a waist–trunk system for a humanoid robot. Mechanism and Machine Theory, 2012, 53: 50-65.
[20] G Zeglin. Uniroo--a one legged dynamic hopping robot. Department of Mechanical Engineering, Massachusetts Institute of Technology, 1991.
[21] P Supinee. Atlas robot improvement. Symposium of University Research and Creative Expression, 2021.
[22] S Dafarra, S Bertrand, R J Griffin, et al. Non-linear trajectory optimization for large step-ups: Application to the humanoid robot atlas. 2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Las Vegas, NV, USA, February 10, 2021: 3884-3891.
[23] H Chen, P M Wensing, W Zhang. Optimal control of a differentially flat two-dimensional spring-loaded inverted pendulum model. IEEE Robotics and Automation Letters, 2019, 5(2): 307-314.
[24] K Yuan, Z Li. An improved formulation for model predictive control of legged robots for gait planning and feedback control. 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Madrid, Spain, October 1-5, 2018: 1-9.
[25] M H Raibert. Legged robots that balance. The MIT Press, Cambridge, MA, 1985, 250.
[26] M H Raibert. Trotting, pacing and bounding by a quadruped robot. Journal of Biomechanics, 1990, 23: 79-98.
[27] H W Park, P M Wensing, S Kim. Jumping over obstacles with MIT Cheetah 2. Robotics and Autonomous Systems, 2021, 136: 103703.
[28] D Wooden, M Malchano, K Blankespoor, et al. Autonomous navigation for BigDog. 2010 IEEE International Conference on Robotics and Automation, Anchorage, AK, USA, May 3-7, 2010: 4736-4741.
[29] S Ching-Long, C A Klein. An adaptive gait for legged walking machines over rough terrain. IEEE Transactions on Systems, Man, and Cybernetics, 1993, 23(4): 1150-1155.
[30] T Kamioka, H Kaneko, T Takenaka, et al. Simultaneous optimization of ZMP and footsteps based on the analytical solution of divergent component of motion. 2018 IEEE International Conference on Robotics and Automation (ICRA), Brisbane, QLD, Australia, May 21-25, 2018: 1763-1770.
[31] R B McGhee, G I Iswandhi. Adaptive locomotion of a multilegged robot over rough terrain. IEEE Transactions on Systems, Man, and Cybernetics, 1979, 9(4): 176-182.
[32] P Fankhauser, M Bjelonic, C D Bellicoso, et al. Robust rough-terrain locomotion with a quadrupedal robot. 2018 IEEE International Conference on Robotics and Automation (ICRA), Brisbane, QLD, Australia, May 21-25, 2018: 1-8.
[33] J F Gardner. Efficient computation of force distributions for walking machines on rough terrain. Robotica, 1992, 10(5): 427-433.
[34] W Guo, Z Tong, F Gao. A NURBS oriented model for motion design of robot motion planning. Proceedings of 14th IFToMM World Congress (IFToMM World Congress 2015), Taipei, Taiwan, China, 2015.
[35] J Huang, W Z Guo, F Gao. Time-variant NURBS oriented motion design for robot path planning. IEEE International Conference on Robotics and Automation (ICRA 2014), Hong Kong, China, 2014.
[36] R F Lin, W Z Guo, M Li, et al. Novel design of a legged mobile lander for extraterrestrial planet exploration. International Journal of Advanced Robotic Systems, 2017, 14(6): 17298814-17746120.
[37] P Yang, F Gao. Leg kinematic analysis and prototype experiments of walking-operating multifunctional hexapod robot. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2013, 228(12): 2217-2232.