[2] S. Levine, D. Bell, L. Jaros, R. Simpson, Y. Koren and J. Borenstein: “The navchair assistive wheelchair navigation system,” IEEE Trans. Rehab. Eng., vol.7, no.4, pp.443–451, 1999.
[3] D.P. Miller and M.G. Slack: “Design and Testing of a Low-cost Robitc Wheelchair Prototype,” Autonomous Robotics, vol.2, pp.77–88, 1995.
[5] E. Prassler, J. Scholz and P. Fiorini: “MAid: A Robotic Wheelchair Roaming in a Railway Station,” Intl. Conf. on Field and Service Robotics, pp.31–36, 1999.