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Legged robots have the advantage of being able to maneuver rough, unstructured terrains unlike their wheeled counterparts. However, many legged robots require multiple sensors and online computations to specify the gait, trajectory or contact forces in real-time for a given terrain, and these methods can break down when sensory information is unreliable or not available. Over the years, underactuated mechanisms have demonstrated great success in object grasping and manipulation tasks due to their ability to passively adapt to the geometry of the objects without sensors. In this paper, we present an application of underactuation in the design of a legged robot with prismatic legs that maneuvers unstructured terrains under open-loop control using only four actuators – one for stance for each half of the robot, one for forward translation, and one for steering. Through experimental results, we show that prismatic legs can support a statically stable stance and can facilitate locomotion over unstructured terrain while maintaining its body posture.
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Monolithic Desktop Digital Fabrication of Autonomous Walking Robots
The fully automated fabrication of robots has long been a holy grail with the potential to revolutionize various industries, including manufacturing, construction, disaster relief, and space exploration. 3D printing offers a promising approach to automation, but the ability to print entire, complex robots with multiple materials remains limited. Previous approaches have simplified robot manufacturing by using fluidic control circuits, but these rely on labor‐intensive methods like silicone molding and manual assembly, limiting accessibility and replicability. Recent work, including this work, has demonstrated 3D‐printed robotic grippers and crawlers with embedded control circuits, but generating cyclic control outputs for legged locomotion in rough terrain remains challenging. This study addresses the challenge with a monolithic 3D‐printable four‐phase bistable oscillating valve, capable of generating coordinated motion of multiple limbs from a steady source of pressurized air. The ability of the oscillator to control an electronics‐free autonomous legged robot capable of walking on rough terrain, which can be fully fabricated on a desktop 3D printer without postassembly is demonstrated. The robot is operational immediately upon connection to an air supply. This development marks a significant step toward accessible, customizable, and biodegradable autonomous soft robots that can be produced using desktop 3D printers with no human intervention.
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- Award ID(s):
- 2331917
- PAR ID:
- 10641534
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 7
- Issue:
- 5
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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