1. Nishiyama T, Takiuchi F, Ando K, et al. The functional evaluation of future wheelchairs contributing to ecological aid in traveling. In: Proceedings of 4th International Symposium on Environmentally Conscious Design and Inverse Manufacturing, Tokyo, 2005. 844–849
2. Yang Y, Qian H, Wu X, et al. A novel design of tri-star wheeled mobile robot for high obstacle climbing. In: 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems, Vilamoura, 2012. 920–925
3. Sugahara Y, Ohta A, Hashimoto K, et al. Walking up and down stairs carrying a human by a biped locomotor with parallel mechanism. In: 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems, Edmonton, 2005. 1489–1494
4. Yuan J. Stability analyses of wheelchair robot based on “Human-in-the-Loop” control theory. In: IEEE International Conference on Robotics and Biomimetics, Bankok, 2009. 419–424
5. Chen S C, Huang K J, Li C H, et al. Trajectory planning for stair climbing in the leg-wheel hybrid mobile robot quattroped. In: IEEE International Conference on Robotics and Automation, Shanghai, 2011. 1229–1234