We demonstrate a portable system integrated with time comparison,absolute distance ranging,and optical communication(TRC)to meet the requirements of space gravitational wave detection.A 1 km free-space asynchronous tw...We demonstrate a portable system integrated with time comparison,absolute distance ranging,and optical communication(TRC)to meet the requirements of space gravitational wave detection.A 1 km free-space asynchronous two-way optical link is performed.The TRC realizes optical communication with 7.7×10^(−5) bit error rate with a Si avalanche photodiode singlephoton detector,while the signal intensity is 1.4 photons per pulse with the background noise of 3×10^(4) counts per second.The distance measurement uncertainty is 48.3 mm,and time comparison precision is 162.4 ps.In this TRC system,a verticalcavity surface-emitting laser diode with a power of 9.1μW is used,and the equivalent receiving aperture is 0.5 mm.The TRC provides a miniaturization solution for ultra-long distance inter-satellite communication,time comparison,and ranging for space gravitational wave detectors.展开更多
In order to implement 3 D point cloud scanning of small hole structure, which could not be contacted or damaged, we propose a noncontact 3 D measuring method. The system contains a laser triangulation displacement sen...In order to implement 3 D point cloud scanning of small hole structure, which could not be contacted or damaged, we propose a noncontact 3 D measuring method. The system contains a laser triangulation displacement sensor, a Michelson interferometer system and a coordinate measuring machine, with the advantages of non-invasive scanning, fast measurement speed and high precision. Focusing on reconstructing 3 D point cloud data, random sample consensus is used to separate surface data and hole data respectively from the raw dataset. Least square optimization determines the function of the cylinder, as well as hole diameter and inclined angle between the hole and the surface. In the experiment scanning a round hole, the estimated result has diameter error and angle error within 30 μm and 0.2°, respectively. Results manifest the effectiveness and feasibility of this system and express practicality in manufacturing industry.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11804099,62075062,62175067,and 11621404)Research Funds of Happiness Flower ECNU(No.2021ST2110).
文摘We demonstrate a portable system integrated with time comparison,absolute distance ranging,and optical communication(TRC)to meet the requirements of space gravitational wave detection.A 1 km free-space asynchronous two-way optical link is performed.The TRC realizes optical communication with 7.7×10^(−5) bit error rate with a Si avalanche photodiode singlephoton detector,while the signal intensity is 1.4 photons per pulse with the background noise of 3×10^(4) counts per second.The distance measurement uncertainty is 48.3 mm,and time comparison precision is 162.4 ps.In this TRC system,a verticalcavity surface-emitting laser diode with a power of 9.1μW is used,and the equivalent receiving aperture is 0.5 mm.The TRC provides a miniaturization solution for ultra-long distance inter-satellite communication,time comparison,and ranging for space gravitational wave detectors.
基金supported by the National Natural Science Foundation of China(Nos.11774095,11804099 and 11621404)the Shanghai Basic Research Project(No.18JC1412200)。
文摘In order to implement 3 D point cloud scanning of small hole structure, which could not be contacted or damaged, we propose a noncontact 3 D measuring method. The system contains a laser triangulation displacement sensor, a Michelson interferometer system and a coordinate measuring machine, with the advantages of non-invasive scanning, fast measurement speed and high precision. Focusing on reconstructing 3 D point cloud data, random sample consensus is used to separate surface data and hole data respectively from the raw dataset. Least square optimization determines the function of the cylinder, as well as hole diameter and inclined angle between the hole and the surface. In the experiment scanning a round hole, the estimated result has diameter error and angle error within 30 μm and 0.2°, respectively. Results manifest the effectiveness and feasibility of this system and express practicality in manufacturing industry.
