| The trend of mechanical manufacturing industry in twenty-first century is four modernizations:flexibility, agility, information and intelligence, which is the final goal of the development of mechanical industry. The system integration technology is the key of intelligent machine. One of the important scientific problems of national guideline on medium and long term program for science and technology development is integration scientific theoretical system, which is based on precision machinery system integration.It is the fundamental guarantee for the development of intelligent machine that detection technology and the measured system are integrated. The more flexible and intelligent the system has, the more integrated sensors and mechanical and electrical products need. The integration depends mainly on two aspects of technical progress. One is that sensors have been made smaller and smaller such as temperature sensor, vibration sensor and noise sensor etc, which can be embedded into the measured system. The other is new materials that have its own perception and conversion function obtained a great development. In precision machinery system, due to the limits of adverse working conditions and compact structure, the general displacement sensor especially for precision and ultra-precision measurement can not be embedded into the system. This has seriously restricted that machinery system really and comprehensively realizes intelligence.Writer’s group has designed displacement sensors which use time clock pulses as the measurement reference, named as time grating. With ten years of development, magnetic field type time grating technology has been gradually matured. In this context, based on the previous time grating research this dissertation focuses on embedded time grating sensing technology research. According to the structure characteristics of time grating sensor, which can only use mechanical equal diversion realize measurement equal diversion, the moving parts of mechanical system are integrated as parts of the sensor, then the embedded position detection can be realized in machinery system. The main research contents and innovations are as follows:1) From the time-space transformation of measurement reference theory, this dissertation illustrates that the key factor for embedded time grating sensor is building the moving coordinate system with constant scanning speed. Therefore, this dissertation summarize systematically three constant motions, i.e. mechanical motion, configured traveling wave and natural traveling wave. The producing mechanism, characteristics and applications have been compared between configured traveling wave and natural traveling wave. Based on further study on the embedded time grating sensing mechanism, a innovative method for electric traveling wave producing is proposed.2) This paper proposes the corresponding relationship between probe and rotor cogging, and designs two structure forms of embedded time grating angular displacement sensors:double-layer winding type and triple-layer winding type. The principles of the sensors are analyzed and the electrical system that concludes hardware and software is designed.3) The experiment system has been designed, and a lot of experiments aiming at two sensors have been studied. The results show that the double-layer winding type embedded time grating angular displacement sensor’s stability, repeatability and measurement accuracy have respectively reached 0.5",0.6" and ±2,4", and the triple-layer winding type embedded time grating angular displacement sensor’s stability, repeatability and measurement accuracy have reached 0.8",0.6" and ±3.4", respectively. On the basis of experiment results, systematic errors and random errors are detailed analyzed, which discussed the sources and influence of long and short period error. A method by using multiple probes is presented, which is different from the traditional method and can effectively reduce the sensor’s systematic errors.4) Based on the characteristics of embedded time grating angular displacement sensor’s structure and error, two self-calibration methods have been proposed, which are Fixed Angle Shift (FAS) method and Difference Quotient Method (DQM). The theoretical derivation and mathematical modeling have been completed for the two methods, and a lot of experiments have been researched. The results show that by using FAS the precision of the sensor is up ±3.5", which is close to the precision of comparison calibration, and by using DQM the precision is up ±4.4".5) Based on embedded time grating sensing technology, large rotary table bearings with measuring system YRTM460 has been developed. The measuring principle, processing and probe designing methods are analyzed in detail. The test platform which is used to test performance index of YRTM460 is set up. The result shows that its performance meets the needs that stability, repeatability and measurement accuracy have respectively reached 0.4",0.5" and ±3.5". At present, cooperating with Harbin Measuring and Cutting Tool Group, the product has been introduced to society at the 14th China International Machine Tool Show in April 20-25,2015. In addition, the cooperation with Luoyang Hongyuan Bearing Technology Co.,Ltd are under way.In summary, based on the previous time grating research, the embedded time grating sensing technology has been researched. In the light of time grating sensor’s measurement model, three constant motions are systematically summarized and a innovative method for electric traveling wave producing is proposed. Two structure forms of embedded time grating angular displacement sensors have been designed and a lot of experiments have been studied. According to the characteristics of sensor’s structure and error, two self-calibration methods are proposed. Theoretical basis and implement methods can be provided for the further researches on the other forms of embedded time grating sensing technology.
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