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This paper presents our work over the last decade in developing functional microrobotic systems, which include wireless actuation of microrobots to traverse complex surfaces, addition of sensing capabilities, and independent actuation of swarms of microrobots. We will discuss our work on the design, fabrication, and testing of a number of different mobile microrobots that are able to achieve these goals. These microrobots include the microscale magnetorestrictive asymmetric bimorph microrobot ( μ MAB), our first attempt at magnetic actuation in the microscale; the microscale tumbling microrobot ( μ TUM), our microrobot capable of traversing complex surfaces in both wet and dry conditions; and the micro-force sensing magnetic microrobot ( μ FSMM), which is capable of real-time micro-force sensing feedback to the user as well as intuitive wireless actuation. Additionally, we will present our latest results on using local magnetic field actuation for independent control of multiple microrobots in the same workspace for microassembly tasks.
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3D‐Printed Microrobots with Integrated Structural Color for Identification and Tracking
The implementation of two‐photon polymerization (TPP) in the microrobotics community has permitted the fabrication of complex 3D structures at the microscale, creating novel platforms with potential biomedical applications for minimizing procedure invasiveness and diagnosis accuracy. Although advanced functionalities for manipulation and drug delivery tasks have been explored, one remaining challenge is achieving improved visualization, identification, and accurate closed‐loop control of microscale robots. To enable this, distinguishable identifying and trackable features must be included on the microrobot. Toward this end, the construction of micro‐ and nanoscale patterns using TPP is demonstrated for the first time on microrobot surfaces with the intent of mimicking color‐expressing nanostructures present on beetles or butterflies. The patterns provide identification and tracking targets due to their vivid color expression under visible light. Helical and rectangular microrobots are designed with the topical patterns and further functionalized with magnetic materials to be externally actuated by magnetic fields. Vision‐based tracking of a 20 μm × 30 μm colored feature on a 100 μm‐long helical microrobot using a fixed angular position light source during microrobotic motion is shown. This versatile structural color patterning approach shows great potential for the visual differentiation of various microrobots and tracking for improved closed‐loop control.
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- Award ID(s):
- 1637961
- PAR ID:
- 10155200
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 2
- Issue:
- 5
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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