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We present a real-time spectral-scanning frequency-modulated continuous wave (FMCW) 3D imaging and velocimetry system that can produce 3D depth maps at 33 Hz, with 48° × 68° field of view (FOV) and 32.8-cm depth range. Each depth map consists of 507 × 500 pixels, with 0.095° × 0.14° angular resolution and 2.82-mm depth resolution. The system employs a grating for beam steering and a telescope for angular FOV magnification. Quantitative depth, reflectivity, and axial velocity measurements of a static 3D printed depth variation target and a moving robotic arm are demonstrated.
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The Actuation Mechanism of 3D Printed Flexure-Based Robotic Microtweezers
We report on the design and the modeling of a three-dimensional (3D) printed flexure-based actuation mechanism for robotic microtweezers, the main body of which is a single piece of nylon. Our design aims to fill a void in sample manipulation between two classes of widely used instruments: nano-scale and macro-scale robotic manipulators. The key component is a uniquely designed cam flexure system, which linearly translates the bending of a piezoelectric bimorph actuator into angular displacement. The 3D printing made it possible to realize the fabrication of the cam with a specifically calculated curve, which would otherwise be costly using conventional milling techniques. We first characterized 3D printed nylon by studying sets of simple cantilevers, which provided fundamental characteristics that could be used for further designs. The finite element method analysis based on the obtained material data matched well with the experimental data. The tweezers showed angular displacement from 0° to 10° linearly to the deflection of the piezo actuator (0–1.74 mm) with the linearity error of 0.1°. Resonant frequency of the system with/without working tweezer tips was discovered as 101 Hz and 127 Hz, respectively. Our design provides simple and low-cost construction of a versatile manipulator system for samples in the micro/meso-scale (0.1–1 mm).
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- Award ID(s):
- 1809047
- PAR ID:
- 10143695
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 10
- Issue:
- 7
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 470
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/mi10070470
