Study On The Planar Shared Magnetic Field Absolute Angular Displacement Sensor

With the development of industrial society,traditional manufacturing is gradually approaching automation and intelligence.As position feedback,the displacement sensor plays a very important role in industrial processing and manufacturing.In recent years,the rapid development of industrial robots,unmanned driving and high-precision machine tools has put forward new requirements for the performance of angular displacement sensors.The angular displacement sensor not only needs to miniaturize the sensor's structural size under the premise of ensuring accuracy,but also needs to be applied to occasions where the ratio of inner and outer diameters is large.The resolver and inductive synchronizer in the angular displacement sensor are bulky and bulky.The photoelectric encoder is not suitable for dust and oily environments.In recent years,the rapid development of Zettlex and Netzer sensors have advantages in volume,quality,and reliability,but they do exist Technology monopoly.Therefore,in the industrial field,there is an increasing demand for sensors with smaller structures and large inner and outer diameter ratios.In response to this situation,this topic proposes a research on an absolute angular displacement sensor based on a shared magnetic field,which uses PCB(Printed Circuit Board)technology The stator part is designed as a structure where two groups of induction coils share the toroidal magnetic field generated by the inner and outer ring excitation coils,and the rotor part is designed as a structure with a double-layer copper foil array.The sensor can not only realize the miniaturization of the structure,but also be suitable for occasions with a large ratio of inner and outer diameters.The main research contents of this subject are as follows:(1)Through the research on the status quo of resolver,inductosyn,Zettlex Incoder sensor and time grating displacement sensor,their characteristics are analyzed,and the results show that the planar magnetic field type angular displacement sensor is used in many occasions,especially the occasions where the ratio of inner and outer diameter is large.Have strong competitiveness.(2)According to the theory of electromagnetics and the precise restraint research of the time-varying magnetic field of the coil,this project proposes a scheme in which the two sets of induction coils of the sensor share the magnetic field generated by one excitation coil,so that the output signal of the induction coil and the displacement signal between the measured angular displacement There is a sinusoidal relationship,and at the same time,the combined relationship of the two sets of sensing signals is used to achieve absolute measurement.(3)Based on the theoretical analysis of the sensor,two physical models of the sensor are designed: a single-layer copper foil structure sensor model and a double-layer copper foil structure sharing a magnetic field absolute angular displacement sensor model.Then,the two sensor models are simulated and analyzed,and the simulation results of the two sensors are analyzed and compared.The results show that the shared magnetic field absolute angular displacement sensor meets the design requirements.(4)The signal processing circuit of the sensor is designed and an experiment platform is built.The designed signal processing circuit can generate a higher frequency excitation signal,demodulate the sensor induction signal,and calculate the angular displacement of the sensor from the demodulated signal.(5)Design sensor prototypes and conduct precision experiments.In this subject,three sensor prototypes with different repetition cycles are designed,and then precision experiments are performed on them respectively.The experimental results show that under the same experimental conditions,the sensor with 5&44 repetition cycles has higher accuracy than the other two sensors.Its accuracy is within the repetition period,and the error is-46 "?+87".