The Robotic Mule
SBIR FY03.2 Topic A03-242
Department of Defense (DoD)/ARMY - Tank Automotive RD&E Center (TARDEC)

The entire solicitation may be viewed at

A03-242 TITLE: The Robotic Mule

TECHNOLOGY AREAS: Ground/Sea Vehicles


OBJECTIVE: The objective of this SBIR topic is to build a legged robotic Mule for troop support and payload carrying.

DESCRIPTION: Robotics is an area of increased interest in the Defense community. With an increased reliance on robotic vehicles, alternate mobility mechanisms must be examined. On narrow mountain passes or heavily forested trails, there is no room to widen the wheelbase of a vehicle in order to increase stability under a payload. Because of the inherent high center of gravity of a quadraped or biped robot, legged robots are well suited to this task. When you think about it, the best way to increase payload on a narrow trail is to build a taller, not wider vehicle. The ability to adjust center of gravity and gait is key to a successful robotic "Mule."

PHASE I: This vehicle should be designed from the beginning with payload capacity in mind. A payload fraction of 25% should be a design goal. Phase I should investigate ways to adjust the gait and posture of the robot under heavy loading.

PHASE II: The final design will be built and tested in Phase II with a heavy emphasis on testing. It is the author's opinion that several changes will need to be made in control algorithms upon testing of the final design. That is why I suggest that final assembly of the prototype should occur approximately 3/4 of the way through Phase II.

PHASE III DUAL USE APPLICATIONS: While many commercial uses are available for a walking payload robot, probably the most viable would be in the toy and household markets. The government would greatly benefit from having a US commercial base in legged robotics, because right now, there is really only a base in Japan and Europe, greatly hindering our ability to develop cutting edge robotics. This is why we are very interested in partnering with industry to develop a core capability in the US.

1) A. Kuo "Energetics of actively powered locomotion using the simplest walking model". J. Biomechanical Engineering 124, 113-120 February 2002.
2) E.Z. Moore and M. Buehler, "Stable Stair Climbing in a Simple Hexapod", 4th Int. Conf. on Climbing and Walking Robots, Karlsruhe, Germany, September 2001.
3) J. Pratt "Exploiting Inherent Robustness and Natural Dynamics in the Control of Bipedal Walking Robots" Ph.D. Thesis MIT June 2000.
4) M. Garcia, et. al. "The Simplest Walking Model: Stability, Complexity, and Scaling". J. Biomechanical Engineering February 1998.
5) T. McGeer "Passive dynamic walking". International Journal of Robotics Research April 1990.

KEYWORDS: robotics, legged robotics, dynamic stability

Questions about SBIR and Solicitation Topics


Paul Muench

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