Design and research of a novel non-contact vertical inductive torque sensor

This paper deals with modal analysis through 3 different approaches, namely: analytically, numerically and experimentally. The investigated mechanical structure in this case will be a beam, which is characterized by three parameters, one of which is significantly larger than the other two. The beam is a structural element designed to transmit forces, mostly external ones. Modal analysis of the beam will be performed in 2 versions of its fixation, as a free structure and a one-sided embedded fixation. Modal parameters obtained by 3 different approaches will be compared with each other, which will determine whether the method of calculation was chosen correctly or whether the experiment was performed correctly.

/pdf/modal-analysis-of-beam-oscillation-3scnopg9z0.pdf

Modal Analysis of Beam Oscillation

A sensor for measuring the crankshaft angle of the main engine in ships is designed. Compared with the existing crankshaft angle encoder, this design’s advantage is that there is no need to add a gear system at the free end of the crankshaft, reducing machining complexity. The purpose of providing high angle resolution over a wide speed range is achieved. Inductive angular displacement sensors (IADSs) require an eddy current magnetic field as a medium to generate the induced voltage. The induced voltage also requires a complex linearization calculation to obtain a linear relationship between angle and voltage. Therefore, a model of the inductive angular displacement sensor based on magnetic focusing (IADSMF) is proposed. Magnetic focusing is introduced into the IADS to replace the eddy current magnetic field with a focusing magnetic field. The main disadvantage of traditional IADSs, which is that they cannot reduce the eddy current magnetic field, is mitigated. An approximate square−shaped focusing magnetic field (12.4 × 12.4 mm2) is formed using the magnetic field constraint of the magnetic conductor. When the receiving coil undergoes a position change relative to the square−shaped focusing magnetic field, the voltage generated via the receiving coil is measured using the electromagnetic induction principle to achieve angular displacement measurement. A mathematical model of the IADSMF is derived. Induced voltages at different frequencies and rotational speeds are simulated and analyzed via MATLAB. The results show that frequency is the main factor affecting the induced voltage amplitude. The sensitivity of the IADSMF is 0.2023 mV/°. The resolution and measurement of the IADSMF range from 0.06° and 0–360°. Compared with a conventional planar coil−based IADS, the eddy current loss is reduced from 2.1304 to 0.3625 W. Direct linearization of the angular displacement with the induced voltage is achieved through designing a square−shaped focusing field and receiving coil. After optimizing the sensor structure with the optimization algorithm, the linearity error is 0.6012%. Finally, this sensor provides a theoretical basis and research ideas for IADS development in ships and navigation.

/pdf/modelling-linearity-analysis-and-optimization-of-an-1p69r686.pdf

Modelling, Linearity Analysis and Optimization of an Inductive Angular Displacement Sensor Based on Magnetic Focusing in Ships

In the post-epidemic era, there is an endless supply of epidemic prevention products that cover a wide range of public areas. The introduction of such products has eased the tense pattern of virus proliferation in the context of the epidemic, and effectively demonstrated the initiatives implemented by the Chinese people in response to the outbreak. This paper therefore begins with the study of contactless epidemic prevention products, which appear in a form that meets the needs of contemporary society and offers a new mode of living to it. It enriches the measures for epidemic prevention and control. By obtaining satisfaction ratings from the user community, the performance of such products can be understood in time to provide a substantial basis for the subsequent upgrading and optimization or transformation of such products. This study uses the KJ method and questionnaires to construct an index system for contactless epidemic prevention products, grasp users’ needs for epidemic prevention products in real time, classify and identify such products, and select such products as epidemic prevention smart security gates, medical delivery robots, infrared handheld thermometers, thermographic body temperature screening, contactless inductive lift buttons, and contactless medical vending machines. The questionnaire was designed with four dimensions: safety, intelligence, aesthetics and economy. A sample size of 262 was collected through the distribution of questionnaires. We used AHP and entropy weighting methods for the comprehensive evaluation; AHP basically tells us how satisfied most users are with this type of product. The use of the entropy weighting method can achieve objectivity in the weighting process. Combining the two approaches helps to improve the scientific nature of the weighting of the evaluation indexes for contactless and epidemic-proof products. It is clear from the AHP analysis that, firstly, there are differences in the perceptions of the performance of this type of product between different age groups. Secondly, the user group rated the perceived performance of the product presented as high (Bn>0.200), which users can subjectively and directly perceive. Next, the perceived future sustainable economic development of this product category is low (Bn≤0.200), and users place low importance on its economic aspects as an objective additional condition. The entropy method of analysis shows that, under reasonable government control of the market for intelligent products, the safety, intelligence and aesthetic effects of these products are significant (Cm≤0.100); further, the economic presentation of these products has yet to be optimized and upgraded (Cm>0.100).

/pdf/evaluation-study-on-the-use-of-non-contact-prevention-and-1ug5d0s2.pdf

Evaluation Study on the Use of Non-Contact Prevention and Protection Products in the Context of COVID-19: A Comprehensive Evaluation Method from AHP and Entropy Weight Method

This article presents a theoretical study of an absolute, ratiometric inductive position sensor (IPS) based on eddy currents. The aim is to describe the working principle of the sensor, having as key components a transmitting coil, the receiving coils, and the conductive target, by introducing area-of-overlap functions. We show that each target–receiver pair needs the adoption of a different reconstruction formula for the identification of the target position, whereas in the literature the usual inverse tangent function is applied for every possible pair. Then, we seek the target–receiver pair that maximizes the amplitude of the induced voltages on the receivers. The results show that to achieve the maximum value of the induced voltages, the best choice is to have a rectangular target and rectangular receivers. To verify the theory, a simulation and optimization method has been applied to the rectangular receiver coils on two rotary IPS realized with printed circuit board (PCB) technology. Measurements performed on the prototypes have shown an increment of the induced voltage of more than 57% with respect to the commonly used sinusoidal receivers. However, a linearity error of 1.5%FS is obtained by using the inverse tangent reconstruction formula. When using the formula provided by the theory, the linearity error becomes 0.6%FS for the nonoptimized prototype and below 0.15%FS for the optimized one.

Study and Design of Ratiometric Inductive Position Sensors Using Area-of- Overlap Functions

Design and parameter optimization of contactless vertical inductive angle sensor

The invention provides a magnetically-focused split integrated sensor and a rotating speed, torque and angle calculation method, belongs to the technical field of sensors and solves the problem that existing sensors for measuring rotating speed, torque and angle of shafts have high size requirements on the shafts, poor matchability and difficulty in zero point finding. The sensor comprises a to-be-measured shaft and collection mechanisms, two ends of the to-be-measured shaft serve as a shaft input end and a shaft output end respectively, the collection mechanisms are arranged at the shaft input end and the shaft output end respectively, each collection mechanism comprises a rotor circuit board, a receiving coil, a shell and an exciting coil, each rotor circuit board and the corresponding receiving coil are printed on a receiving coil flexible circuit board, and a signal processing circuit is printed on each receiving coil. The sensor is mainly used for measuring and calculating rotating speed, torque and angle of a shaft.

Magnetically-focused split integrated sensor and rotating speed, torque and angle calculation method

The invention discloses a measuring system and a measuring method for measuring static torque based on a magnetic focusing mode A static torque sensor comprises a rotating shaft, a first magnetic conductance unit and a second magnetic conductance unit The first magnetic conductance unit comprises an excitation device A and a receiving coil A, the excitation device A comprises a magnetic guidingapparatus A and a group of excitation coils A, one end of the rotating shaft is externally sleeved with the receiving coil A, three magnetic guiding apparatuses A are evenly distributed at the outer end of the receiving coil A, a group of excitation coils A is arranged outside each magnetic guiding apparatus A, a housing A-1 and a housing A-2 are arranged outside the three excitation coils A in acovering mode, the housing A-1 and the housing A-2 are used in cooperation to form an annular housing A, and the second magnetic conductance unit and the first magnetic conductance unit are the same in structure When the rotating shaft receives a starting signal, an actual rotating stage is started, and the moment of the system resistance and other frictional resistances needing to be overcome inthe process can be measured by the sensor

Wang Bonan

Papers

Design and parameter optimization of contactless vertical inductive angle sensor

Magnetically-focused split integrated sensor and rotating speed, torque and angle calculation method

Measuring system and measuring method for measuring static torque based on magnetic focusing mode