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arXiv · 2602.22118

System Design of the Ultra Mobility Vehicle: A Driving, Balancing, and Jumping Bicycle Robot

Benjamin Bokser·Daniel Gonzalez·Aaron Preston·Alex Bahner·Annika Wollschläger·Arianna Ilvonen·Asa Eckert-Erdheim·Ashwin Khadke·Bilal Hammoud·Dean Molinaro·Fabian Jenelten·Henry Mayne·Howie Choset·Igor Bogoslavskyi·Itic Tinman·James Tigue·Jan Preisig·Kaiyu Zheng·Kenny Sharma·Kim Ang·Laura Lee·Liana Margolese·Nicole Lin·Oscar Frias·Paul Drews·Ravi Boggavarapu·Rick Burnham·Samuel Zapolsky·Sangbae Kim·Scott Biddlestone·Sean Mayorga·Shamel Fahmi·Surya Singh·Tyler McCollum·Velin Dimitrov·William Moyne·Yu-Ming Chen·Farbod Farshidian·Marco Hutter·David Perry·Al Rizzi·Gabe Nelson
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Abstract

Trials cyclists and mountain bike riders can hop, jump, balance, and drive on one or both wheels. This versatility allows them to achieve speed and energy-efficiency on smooth terrain and agility over rough terrain. Inspired by these athletes, we present the design and control of a robotic platform, Ultra Mobility Vehicle (UMV), which combines a bicycle and a reaction mass to move dynamically with minimal actuated degrees of freedom. We employ a simulation-driven design optimization process to synthesize a spatial linkage topology with a focus on vertical jump height and momentum-based balancing on a single wheel contact. Using a constrained Reinforcement Learning (RL) framework, we demonstrate zero-shot transfer of diverse athletic behaviors, including track-stands, jumps, wheelies, rear wheel hopping, and front flips. This 23.5 kg robot is capable of high speeds (8 m/s) and jumping on and over large obstacles (1 m tall, or 130% of the robot's nominal height).

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Benjamin Bokser, Daniel Gonzalez, Aaron Preston, Alex Bahner, Annika Wollschläger, Arianna Ilvonen, Asa Eckert-Erdheim, Ashwin Khadke, Bilal Hammoud, Dean Molinaro, Fabian Jenelten, Henry Mayne, Howie Choset, Igor Bogoslavskyi, Itic Tinman, James Tigue, Jan Preisig, Kaiyu Zheng, Kenny Sharma, Kim Ang, Laura Lee, Liana Margolese, Nicole Lin, Oscar Frias, Paul Drews, Ravi Boggavarapu, Rick Burnham, Samuel Zapolsky, Sangbae Kim, Scott Biddlestone, Sean Mayorga, Shamel Fahmi, Surya Singh, Tyler McCollum, Velin Dimitrov, William Moyne, Yu-Ming Chen, Farbod Farshidian, Marco Hutter, David Perry, Al Rizzi, Gabe Nelson. 2026-02-25. System Design of the Ultra Mobility Vehicle: A Driving, Balancing, and Jumping Bicycle Robot. https://arxiv.org/abs/2602.22118

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