Magnetic modular cubes are cube-shaped bodies with embedded permanent magnets. The cubes are uniformly controlled by a global time-varying magnetic field.A 2D physics simulator is used to simulate global control and the resulting continuous movement of magnetic modular cube structures. We develop local plans, closed-loop control algorithms for planning the connection of two structures at desired faces. The global planner generates a building instruction graph for a target structure that we traverse in a depth-first-search approach by repeatedly applying local plans.We analyze how structure size and shape affect planning time. The planner solves 80% of the randomly created instances with up to 12 cubes in an average time of about 200 seconds.
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Closed-Loop Control of Magnetic Modular Cubes for 2D Self-Assembly
Reconfigurable modular robots can dynamically
assemble/disassemble to accomplish the desired task better.
Magnetic modular cubes are scalable modular subunits with
embedded permanent magnets in a 3D-printed cubic body and
can be wirelessly controlled by an external, uniform, timevarying
magnetic field. This paper considers the problem of
self-assembling these modules into desired 2D polyomino shapes
using such magnetic fields. Although the applied magnetic field
is the same for each magnetic modular cube, we use collisions
with workspace boundaries to rearrange the cubes. We present a
closed-loop control method for self-assembling the magnetic modular
cubes into polyomino shapes, using computer vision-based
feedback with re-planning. Experimental results demonstrate
that the proposed closed-loop control improves the success rate of
forming 2D user-specified polyominoes compared to an open-loop
baseline. We also demonstrate the validity of the approach over
changes in length scales, testing with both 10mm edge length
cubes and 2.8mm edge length cubes.
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- PAR ID:
- 10440445
- Editor(s):
- Ani Hsieh
- Date Published:
- Journal Name:
- IEEE Robotics and Automation Letters
- ISSN:
- 2377-3774
- Page Range / eLocation ID:
- 1 to 8
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Kirigami, the ancient paper art of cutting, has recently emerged as a new approach to construct metamaterials with novel properties imparted by cuts. However, most studies are limited to thin sheets‐based 2D kirigami metamaterials with specific forms and limited reconfigurability due to planar connection constraints of cut units. Here, 3D modular kirigami is introduced by cutting bulk materials into spatially closed‐loop connected cut cubes to construct a new class of 3D kirigami metamaterials. The module is transformable with multiple degrees of freedom that can transform into versatile distinct daughter building blocks. Their conformable assembly creates a wealth of reconfigurable and disassemblable metamaterials with diverse structures and unique properties, including reconfigurable 1D column‐like materials, 2D lattice‐like metamaterials with phase transition of chirality, as well as 3D frustration‐free multilayered metamaterials with 3D auxetic behaviors and programmable deformation modes. This study largely expands the design space of kirigami metamaterials from 2D to 3D.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/LRA.2023.3296008
