Design and control of a spherical omnidirectional blimp. - Michael Burri; Laura Gasser; M. Käch; Matthias Krebs; S. Laube; Anton Ledergerber; Daniel Meier; R. Michaud; Lukas Mosimann; L. Müri; Claudio Ruch; Andreas Schaffner; et al. (IROS, 2013)