Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change tradi...Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with measurement software. The laser alignment system with dual PSDs was improved on a single PSD system, and yields higher measurement accuracy than the previous design, and has been successful for designing and implements actual shaft alignment. In the system, the range of offset measurement is ±4 mm, and the resolution is 1.5 μm, with accuracy being less than 2 μm.展开更多
A new non-contact inspection technique based on laser-PSD （position sensitive detector） to inspect the inner surface of small-diameter pipe is proposed,and the corresponding sensor has been developed. After being re...A new non-contact inspection technique based on laser-PSD （position sensitive detector） to inspect the inner surface of small-diameter pipe is proposed,and the corresponding sensor has been developed. After being reflected by two mirrors in series,a laser beam is projected onto the inner wall of a pipe as a small light spot and is read by a two-dimensional PSD. Based on the signals from the PSD and the structure parameters of the sensor,the spot position on the wall can be calculated in a local 3D coordinate system. The spot controlled by the micro-motor driven mirrors will scan a closed section ring on the inner wall of the pipe to obtain the relative coordinates of all the sampled points. The data will be then processed through data segmentation and least square fitting,to reconstruct the section curve used for obtaining the radius and the defect description of the section. Driven by a micro-pipe robot,the sensor can inspect a long curved pipe and obtain its 3-D reconstruction. An inspection system based on this technique can detect the mini-diarneter pipe with an inner diameter of 9.5 mm-10.5 mm and a curvature radius larger than 100 mm at a measurement accuracy of the inner surface defect of ±0.1 mm.展开更多
基金Project (No. 60337030) partly supported by the National NaturalScience Foundation of China
文摘Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with measurement software. The laser alignment system with dual PSDs was improved on a single PSD system, and yields higher measurement accuracy than the previous design, and has been successful for designing and implements actual shaft alignment. In the system, the range of offset measurement is ±4 mm, and the resolution is 1.5 μm, with accuracy being less than 2 μm.
文摘A new non-contact inspection technique based on laser-PSD （position sensitive detector） to inspect the inner surface of small-diameter pipe is proposed,and the corresponding sensor has been developed. After being reflected by two mirrors in series,a laser beam is projected onto the inner wall of a pipe as a small light spot and is read by a two-dimensional PSD. Based on the signals from the PSD and the structure parameters of the sensor,the spot position on the wall can be calculated in a local 3D coordinate system. The spot controlled by the micro-motor driven mirrors will scan a closed section ring on the inner wall of the pipe to obtain the relative coordinates of all the sampled points. The data will be then processed through data segmentation and least square fitting,to reconstruct the section curve used for obtaining the radius and the defect description of the section. Driven by a micro-pipe robot,the sensor can inspect a long curved pipe and obtain its 3-D reconstruction. An inspection system based on this technique can detect the mini-diarneter pipe with an inner diameter of 9.5 mm-10.5 mm and a curvature radius larger than 100 mm at a measurement accuracy of the inner surface defect of ±0.1 mm.
