Guangjun Liu Xiaojia He Jing Yuan Sajan Abdul Andrew A. Goldenberg Development of modular and reconfigurable robot with multiple working modes. 3502-3507 2008 ICRA http://dx.doi.org/10.1109/ROBOT.2008.4543746 conf/icra/2008 db/conf/icra/icra2008.html#LiuHYAG08