Current aerial robots demonstrate limited interaction capabilities in unstructured environments when compared with their biological counterparts. Some examples include their inability to tolerate collisions and to successfully land or perch on objects of unknown shapes, sizes, and texture. Efforts to include compliance have introduced designs that incorporate external mechanical impact protection at the cost of reduced agility and flight time due to the added weight. In this work, we propose and develop a lightweight, inflatable, soft-bodied aerial robot (SoBAR) that can pneumatically vary its body stiffness to achieve intrinsic collision resilience. Unlike the conventional rigid aerial robots, SoBAR successfully demonstrates its ability to repeatedly endure and recover from collisions in various directions, not only limited to in-plane ones. Furthermore, we exploit its capabilities to demonstrate perching where the three-dimensional collision resilience helps in improving the perching success rates. We also augment SoBAR with a novel hybrid fabric-based bistable (HFB) grasper that can utilize impact energies to perform contact-reactive grasping through rapid shape conforming abilities. We exhaustively study and offer insights into the collision resilience, impact absorption, and manipulation capabilities of SoBAR with the HFB grasper. Finally, we compare the performance of conventional aerial robots with the SoBAR through collision characterizations, grasping identifications, and experimental validations of collision resilience and perching in various scenarios and on differently shaped objects.
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Design, Characterization and Control of a Whole-body Grasping and Perching (WHOPPEr) Drone
Flying robots can exploit perching abilities to position themselves on strategically-chosen locations and monitor the areas of interest from a critical vantage point. Moreover, they can significantly extend their battery life by turning off the propulsion systems when carrying out a surveillance mission. However, unknown disturbances arise from the physical interactions between the robot and the object, making it challenging to stabilize the robot during perching. In this paper, we present a Whole-body Grasping and Perching (WHOPPEr) Drone, which is capable of fast and robust perching by utilizing its entire body as the grasper in lieu of an add-on grasper. We first present the design concept, parameter selection and characterization of the novel whole-body grasping drone. Next, we analyze the grasping ability of the morphing chassis and present an aerodynamic analysis for the effect of motor thrust on the compliant arm. We finally demonstrate, via real-time experiments, the performance of WHOPPEr in autonomous perching and payload delivery tasks.
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- Award ID(s):
- 1828010
- PAR ID:
- 10514482
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)
- ISBN:
- 978-1-6654-9190-7
- Page Range / eLocation ID:
- 1 to 7
- Format(s):
- Medium: X
- Location:
- Detroit, MI, USA
- Sponsoring Org:
- National Science Foundation
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