Research of high-speed precision positioning system based on double-frequency laser interference

2015 ◽  
Vol 41 (2) ◽  
pp. 156-161 ◽  
Author(s):  
季林 JI Lin ◽  
侯茂盛 HOU Maosheng ◽  
邱丽荣 QIU Lirong ◽  
马飞 MA Fei ◽  
赵维谦 ZHAO Weiqian
2013 ◽  
Vol 552 ◽  
pp. 446-451
Author(s):  
Wen Jun He ◽  
Yue Gang Fu ◽  
Yang Zheng ◽  
Lei Zhang ◽  
Jia Ke Wang ◽  
...  

A new measuring method of track irregularity for high-speed railway is proposed by using dual-frequency laser interference technique. The linear deviation between the phase-locked gauging head and the center line of the railway route can be calculated by comparing the phase difference variation of the laser beat signal in the test ray path and the reference ray path when the portable track inspection car is moving forward along the track. While we use laser ranging technique to measure gauge, after processing data, the static irregularity of track will be acquired by changing straightness deviation of phase-locked gauging head into straightness deviation of left-right two tracks. The method is different from the existing techniques for detecting high-speed railway irregularity, such as the inertial reference method, the measuring method of chord and the method of laser alignment; it utilized the accuracy of the time to accomplish the high-precision measurement of the space and achieved innovation in theory.


Author(s):  
Chuan Yang ◽  
Zhi Zhang

A two-dimensional ultra-precision positioning system with high-speed and large-range which can be used for micro-nanometer machining has been studied out in this paper. Macro and micro moving system are used to meet the demands of ultra-precision positioning with high-speed and large-range. According to the demands of macro moving system, a valid control of fuzzy-neuron self-adaptive and weighted PID control algorithm with high speed and high precision is proposed. The experimental results show that the error of repeated positioning accuracy is less than 1 μ m for a random point within the range of 300mm by 300mm under the design load for a carrying test-bed with carrying area of 250mm by 250mm. According to the demands of micro moving system, self-adaptive and fuzzy reasoning PID control system based on neural network is studied for the first time. The experimental results show that repeated positioning accuracy is less than 100nm.


Author(s):  
Charly Fornasier-Santos ◽  
Gregoire P Millet ◽  
Paul Stridgeon ◽  
Olivier Girard ◽  
Franck Brocherie ◽  
...  

AbstractThe purpose of this study is to evaluate the influence of competition level on running patterns for five playing position in the most successful 2014–2015 European rugby union team. Seventeen French rugby union championship and seven European rugby Champions Cup games were analysed. Global positioning system (sampling: 10 Hz) were used to determine high-speed movements, high-intensity accelerations, repeated high-intensity efforts and high-intensity micro-movements characteristics for five positional groups. During European Champions Cup games, front row forwards performed a higher number of repeated high-intensity efforts compared to National championship games (5.8±1.6 vs. 3.6±2.3; +61.1%), and back row forwards travelled greater distance both at high-speed movements (3.4±1.8 vs. 2.4±0.9 m·min-1; +41.7%) and after high-intensity accelerations (78.2±14.0 vs. 68.1 ±13.4 m; +14.8%). In backs, scrum halves carried out more high-intensity accelerations (24.7±3.1 vs. 14.8±5.0; +66.3%) whereas outside backs completed a higher number of high-speed movements (62.7±25.4 vs. 48.3±17.0; +29.8%) and repeated high-intensity efforts (13.5±4.6 vs. 9.7±4.9;  +39.2%). These results highlighted that the competition level affected the high-intensity activity differently among the five playing positions. Consequently, training programs in elite rugby should be tailored taking into account both the level of competition and the high-intensity running pattern of each playing position.


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