1. R. Morales, A. Gonzalez, V. Feliu, P. Pintado. Environment adaptation of a new staircase-climbing wheelchair. Autonomous Robots, vol. 23, no. 4, pp. 275–292, 2007.
2. G. Quaglia, W. Franco, R. Oderio. Wheelchair. q, a motorized wheelchair with stair climbing ability. Mechanism and Machine Theory, vol. 46, no. 11, pp. 1601–1609, 2011.
3. J. H. Zhang, X. J. Zhang, M. L. Zhang, F. H. Guo. Eight wheel-legged mobile robot platform design and kinematic analysis. Journal of Machine Design, vol. 29, no. 8, pp. 35–39, 2012. (in Chinese)
4. S. C. Fan, S. H. Han, H. R. Gu. The stability of biped walking robot parallel leg mechanism. Journal of Hebei University of Technology, vol. 33, no. 1, pp. 27-31. (in Chinese)
5. G. Carbone, Y. Sugahara, H. O. Lim, A. Takanishi, M. Cec-carelli. Stiffness performance estimation for biped locomotor WL-15. In Proceedings of IEEE/ASME International Conference on Advanced Intelligent Mechatronics, IEEE, Kobe, Japan, pp. 956–961, 2003.