Multi-turn Absolute Time Grating Encoder Based On Differential Transmission

In the context of the continuous development of industrial technology,the application of precision displacement measurement technology is gradually expanding,and higher requirements for the precision of this technology are put forward in the actual production process.Sensor technology is one of the important foundations of modern information technology,and its performance directly affects the accuracy of the final measurement results.At present,the widely used time grating displacement sensor is a displacement sensor independently developed and produced by my country,which has the function of measuring space quantity.Among them,the electromagnetic induction food frying angle displacement sensor shows strong anti-interference ability and high safety in practical application.Subsequently,it was proposed that in the special situation of the multi-turn absolute time grid based on the differential transmission,the displacement measurement performance of the absolute sensor is required to be higher,including direct reading of information,power-off protection,and higher productivity.At this stage,the measurement methods adopted by the time grating angle displacement sensor are mainly incremental measurement and absolute measurement,and the research related to absolute measurement needs to be continuously deepened.In this paper,by designing a multi-turn absolute time grating encoder based on differential transmission,the multi-turn absolute position measurement is realized by the high-precision measurement of the differential transmission structure and the time grating angle displacement sensor.This article first analyzes the relevant theory of the time grating angle displacement sensor,and then proposes a multi-turn absolute time grating encoder based on differential transmission.The specific principle is to use two pairs of gears to realize the driving wheel within 4096 revolutions,and the relative position of the two gears is unique,so as to realize the absolute position measurement within 4096 revolutions.Then use the time grating displacement sensor to measure the position of the wheel to obtain the relative position of the wheel;in the measurement process,there are mainly two methods,the first is the traditional time grating angular displacement sensor,and the second is the use of the embedded time grating displacement sensor.First,use UG and Autocad software to complete the establishment of the sensor model,and then use Ansoft Maxwell 16.0 to implement electromagnetic field simulation.Data analysis is performed on the traveling wave model obtained from the simulation results,and the error frequency,error size and absolute position are obtained to achieve the output signal to the angle Conversion of displacement information.After obtaining the two parameters from the two sensors,the absolute number of rotations of the driving wheel can be calculated by using the structural principle of the differential transmission.In view of the problem that the photoelectric encoder cannot continue to read when the power is off,the structure of the traditional multi-turn absolute encoder is complicated.This paper proposes a multi-turn absolute time grid encoder based on differential transmission,which not only overcomes the defects of the photoelectric encoder,but also improves the problem of the traditional multi-turn complex transmission chain.First,the principle of the encoder is introduced in detail,including the principle of differential transmission,the principle of time grating angle displacement sensor,and the principle of single-turn absolute position measurement,and the principle of multi-turn absolute position measurement.Then the device is tested through simulation and experiment,and The data is analyzed and processed to get the error,and it is judged that the device can measure the absolute position of multi-turns.Finally,the error brought by the transmission chain to the experiment and the calibration of the transmission error are analyzed.In summary,this article verifies the absolute measurement of the position within 4096 circles through the derivation and analysis of the theoretical model,structural design,simulation and experimental research,and analyzes the main source of error,which is the follow-up study of the absolute encoder Provide a basis.