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It is common for scientists to look to nature for inspiration in developing robots. Many times biological creatures outperform even the best man made robots. We will be focusing on aquatic locomotion of robots inspired by the locomotion of fish. There are two different means of propulsion of the robots tested in this paper. One model of the robot is propelled only through the oscillations of an internal momentum wheel, while the other is propelled by the direct actuation of a tail structure. Both of these models achieve net propulsion through vortex shedding past their trailing edge, and two of the robots locomotion is also aided by the change in shape from either a passive or active tail. Tests were conducted to highlight the locomotion performance differences of the two different means of locomotion.
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Robots with Tails
Abstract Until recently, most four-legged robots have lacked a feature that is found again and again in nature—a tail. Studies of animal locomotion and robots in the laboratory indicate that leaving out tails has been a design drawback. In fact, research conducted by our lab at Virginia Tech has shown that an articulated robotic tail can effectively maneuver and stabilize a quadruped both for static and dynamic locomotion.
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- Award ID(s):
- 1906727
- PAR ID:
- 10326671
- Date Published:
- Journal Name:
- Mechanical Engineering
- Volume:
- 143
- Issue:
- 6
- ISSN:
- 0025-6501
- Page Range / eLocation ID:
- 32 to 37
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The traditional locomotion paradigm of quadruped robots is to use dexterous (multi degrees of freedom) legs and dynamically optimized footholds to balance the body and achieve stable locomotion. With the introduction of a robotic tail, a new locomotion paradigm becomes possible as the balancing is achieved by the tail and the legs are only responsible for propulsion. Since the burden on the leg is reduced, leg complexity can be also reduced. This paper explores this new paradigm by tackling the dynamic locomotion control problem of a reduced complexity quadruped (RCQ) with a pendulum tail. For this specific control task, a new control strategy is proposed in a manner that the legs are planned to execute the open-loop gait motion in advance, while the tail is controlled in a closed-loop to prepare the quadruped body in the desired orientation. With these two parts working cooperatively, the quadruped achieves dynamic locomotion. Partial feedback linearization (PFL) controller is used for the closed-loop tail control. Pronking, bounding, and maneuvering are tested to evaluate the controller’s performance. The results validate the proposed controller and demonstrate the feasibility and potential of the new locomotion paradigm.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.2021-NOV2
