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Robustness, compactness, and portability of tensegrity robots make them suitable candidates for locomotion on unknown terrains. Despite these advantages, challenges remain relating to simplicity of fabrication and locomotion. The paper introduces a design solution for fabricating tensegrity robots of varying morphologies with modular components created using rapid prototyping techniques, including 3D printing and laser-cutting. % It explores different robot morphologies that attempt to balance structural complexity while facilitating smooth locomotion. The techniques are utilized to fabricate simple tensegrity structures, followed by tensegrity robots in icosahedron and half-circle arc morphologies. Locomotion strategies for such robots involve altering of the position of center-of-mass to induce `tip-over'. Furthermore, the design of curved links of tensegrity mechanisms facilitates continuous change in the point of contact (along the curve) as compared to piece-wise continuous in the traditional straight links (point contact) which induces impulse reaction forces during locomotion. The resulting two tensegrity robots - six-straight strut icosahedron and two half-circle arc morphology - achieve locomotion through internal mass-shifting utilizing the presented modular mass-shifting mechanism. The curve-link tensegrity robot demonstrates smooth locomotion along with folding-unfolding capability.
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Proof-of-Concept Designs for the Assembly of Modular, Dynamic Tensegrities into Easily Deployable Structures
Dynamic tensegrity robots are inspired by tensegrity structures in architecture; arrangements of rigid rods and flexible elements allow the robots to deform. This work proposes the use of multiple, modular, tensegrity robots that can move and compliantly connect to assemble larger, compliant, lightweight, strong structures and scaffolding. The focus is on proof-of-concept designs for the modular robots themselves and their docking mechanisms, which can allow the easy deployment of structures in unstructured environments. These mechanisms include (electro)magnets to allow each individual robot to connect and disconnect on cue. An exciting direction is the design of specific module and structure designs to fit the mission at hand. For example, this work highlights how the considered three bar structures could stack to form a column or deform on one side to create an arch. A critical component of future work will involve the development of algorithms for automatic design and layout of modules in structures.
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- Award ID(s):
- 1956027
- PAR ID:
- 10294210
- Date Published:
- Journal Name:
- ASCE Earth and Space Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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