Optical Fiber Bundle-Based High-Speed and Precise Micro-Scanning for Image High-Resolution Reconstruction

We propose an imaging method based on optical fiber bundle combined with micro-scanning technique for improving image quality without complex image reconstruction algorithms. In the proposed method, a piezoelectric-ceramic-chip is used as the micro-displacement driver of the optical fiber bundle, which has the advantages of small volume, fast response speed and high precision. The corresponding displacement of the optical fiber bundle can be generated by precise voltage controlling. An optical fiber bundle with core/cladding diameter 4/80 μm and hexagonal arrangement is used to scan the 1951 USAF target. The scanning step is 1 μm, which is equivalent to the diffraction limit resolution of the optical system. The corresponding information is recorded at high speed through photo-detectors and a high-resolution image is obtained by image stitching processing. The minimum distinguishable stripe width of the proposed imaging technique with piezoelectric-ceramic-chip driven micro-scanning is approximately 2.1 μm, which is 1 time higher than that of direct imaging with a CCD camera whose pixel size is close to the fiber core size. The experimental results indicate that the optical fiber bundle combined with piezoelectric-ceramic-chip driven micro-scanning is a high-speed and high-precision technique for high-resolution imaging.

Theoretical and Experimental Investigations into a Crawling Robot Propelled by Piezoelectric Material

Conventional motors with complicated electromagnetic structures are difficult to miniaturise for millimetre- and centimetre-sized robots. Instead, small-scale robots are actuated using a variety of functional materials. We proposed a novel robot propelled by a piezoelectric ceramic in this work. The robot advances due to the asymmetric friction created by the spikes on the surface. The structural modelling was completed, static and dynamic models were established to predict the moving characteristics, the prototype was built using three dimensional (3D) printing technology, and the models were evaluated via experiments. Compared with conventional inchworm-type robots, the proposed robot is superior in simple structure because the clamping components are replaced by spikes with asymmetric friction. Compared with SMA (shape memory alloy) actuating inchworm-type robots, it has a faster velocity with higher resolution. Meanwhile, the components are printed through an additive manufacturing process that is convenient and avoids assembly errors. This design could make contributions to many areas, such as pipe inspection, earthquake rescue, and medicine delivery.

Design and Performance Analysis of Precision Micro-drive Amplification Mechanism

At present, there are shortcomings in the research of micro-drive amplification mechanism, such as insufficient precision and additional force. In this paper, a kind of micro-drive amplification mechanism is designed and its positioning accuracy is simulated. Firstly, a kind of micro-drive amplification mechanism is designed, which can accurately transform the input displacement of piezoelectric ceramic actuator (PZT) into the output displacement of a certain number of amplification. the theoretical motion magnification ratio of the mechanism is 3:1. Secondly, the kinematics and simulation of the mechanism were studied, and the conversion performance of the mechanism was analyzed. The results showed that the micro-drive amplification mechanism has the advantage of high positioning accuracy (maximum positioning error is 4.67%). Finally, through strength analysis and modal analysis, the performance of micro-drive amplification mechanism is studied. This study has some reference value for the research and application of precision micro-drive amplification mechanism.