Building cubes that can jump up and balance
The Cubli is a 15 × 15 × 15 cm cube that can jump up and balance on its corner. Reaction wheels mounted on three faces of the cube rotate at high angular velocities and then brake suddenly, causing the Cubli to jump up. Once the Cubli has almost reached the corner stand up position, controlled motor torques are applied to make it balance on its corner. In addition to balancing, the motor torques can also be used to achieve a controlled fall such that the Cubli can be commanded to fall in any arbitrary direction. Combining these three abilities -- jumping up, balancing, and controlled falling -- the Cubli is able to 'walk'.
M. Muehlebach, R. D'Andrea, Nonlinear Analysis and Control of a Reaction-Wheel-Based 3-D Inverted Pendulum, in IEEE Transactions on Control Systems Technology, 2016 (early access)
pdf (PDF, 5.1 MB)
M. Muehlebach, G. Mohanarajah, and R. D'Andrea, Nonlinear Analysis and Control of a Reaction Wheel-based 3D Inverted Pendulum, in Proc. Conference on Decision and Control, CDC 2013 (Florence, Italy)
pdf (PDF, 666 KB) | appendix (PDF, 37 KB) | bib (BIB, 240 Bytes)
M. Gajamohan, M. Muehlebach, T. Widmer, and R. D'Andrea, The Cubli: A Reaction Wheel-based 3D Inverted Pendulum, in Proc. European Control Conference (Zurich, Switzerland), pp. 268-274, July 2013.
pdf (PDF, 602 KB) | bib (BIB, 239 Bytes)
M. Gajamohan, M. Merz, I. Thommen, and R. D'Andrea, The Cubli: A Cube that can Jump Up and Balance, in Proc. IEEE/RSJ International Conference of Intelligent Robots and Systems (Algarve, Portugal), pp. 3722-3727, October 2012.
pdf (PDF, 648 KB) | bib (BIB, 254 Bytes)