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This paper is designed to encourage electronic device designers to take a new look at a recent technology, Hall‐effect sensing, that has seen exceptional growth in certain areas, but could find much wider application and acceptance due to new supporting technologies.

The paper introduces Hall‐effect technology, and then explores how it has been applied, in particular, differentiating between the primary types of Hall sensors, and the highly differentiated range of sensing behaviors they can provide. In addition, it explores some of the enabling technologies, such as advances in signal processing, that have made this technology so much more robust than in its earliest days. This allows the application of the extreme high‐reliability benefit of contactless Hall sensing to a broader range of applications than ever before.

In addition to the advances that have made Hall‐effect sensing more practical, there are additional contributions to the designs of complete solutions. These advances include power and space reduction, as well as integration of diagnostic and protection functions that allow Hall sensor ICs to provide the advanced data‐driven features that are becoming more in demand in miniaturized portable consumer electronics, automobiles, and other growing industries.

The research is intended as a general introduction to an emerging, yet complex technology. It is limited to standard configurations, and simplified explanations of magnetic effects.

This paper can be of great value to application designers who specialize in either the mechanical or electrical engineering disciplines, and who would like a cross‐disciplinary introduction to this technology, which requires a foundation in both areas simultaneously. In addition, the somewhat mysterious realm of electromagnetics is presented in a practical way, allowing the reader to gain enough confidence to begin experimenting with this innovative technology.

This study aims to fabricate and manipulate ensemble spin of negative nitrogen-vacancy (NV⁻) centres optimally for future solid atomic magnetometers/gyroscope. Parameters for sample preparation most related to magnetometers/gyroscope are, in particular, the concentration and homogeneity of the NV⁻ centres, the parameters’ microwave antenna of resonance frequency and the strength of the microwave on NV⁻ centres. Besides, the abundance of other impurities such as neutral NV centres (NV⁰) and substitutional nitrogen in the lattice also plays a critical role in magnetic sensing.

The authors succeeded in fabricating the assembly of NV centres in diamond and they determined its concentration of (2-3) × 10¹⁶ cm⁻³ with irradiation followed by annealing under a high temperature condition. They explored a novel magnetic resonance approach to detect the weak magnetic fields that takes advantage of the solid-state electron ensemble spin of NV⁻ centres in diamond. In particular, the authors set up a magnetic sensor on the basis of the assembly of NV centres. They succeeded in fabricating the assembly of NV centres in diamond and determined its concentration. They also clarified the magnetic field intensity measured at different positions along the antenna with different lengths, and they found the optimal position where the signal of the magnetic field reaches the maximum.

The authors mainly reported preparation, initialization, manipulation and measurement of the ensemble spin of the NV centres in diamond using optical excitation and microwave radiation methods with variation of the external magnetic field. They determined the optimal parameters of irradiation and annealing to generate the ensemble NV centres, and a concentration of NV⁻ centres as high as 10¹⁶ cm⁻³ in diamond was obtained. In addition, they found that sensitivity of the magnetometer using this method can reach as low as 5.22 µT/Hz currently.

This research can shed light on the development of an atomic magnetometer and a gyroscope on the basis of the ensemble spin of NV centres in diamond.

High concentration spin of NV⁻ in diamond is one of the advantages compared with that of the atomic vapor cells, because it can obtain a higher concentration. When increasing the spin concentration, the spin signal is easy to detect, and macro-atomic spin magnetometer become possible. This research is the first step for solid atomic magnetometers with high spin density and high sensitivity potentially with further optimization. It has a wide range of applications from fundamental physics tests, sensor applications and navigation to detection of NMR signals.

As has been pointed out, in this research, the authors mainly worked on fabricating NV⁻ centres with high concentration (10¹⁵-10¹⁶ cm⁻³) in diamond by using optimal irradiation and annealing processes, and they quantitatively defined the NV⁻ concentration, which is important for the design of higher concentration processes in the magnetometer and gyroscope. Until now, few groups can directly define the NV⁻ concentration. Besides, the authors optimized the microwave antenna parameters experimentally and explored the dependence between the splitting of the magnetic resonance and the magnetic fields, which dictated the minimum detectable magnetic field.

Advantages claimed by the authors for this type of magnetic sensor for embedding in robot fingers are that it is independent of the rate of approach, it is reliable in hostile environments, and it yields output easily processed by digital electronics.

This paper aims to develop a comprehensive model of a magnetic sensor array that will be operational for a multitude of electric components in continuous and nonintrusive condition monitoring (CM) or in readiness assessment (RA) applications.

A universal nonintrusive model of a flexible antenna array is introduced to monitor and identify failures in electric machine drives. An adjustable sensor is designed to serve as a RA for a vast range of electrical elements in a typical power system by capturing the low-frequency radiated magnetic fields.

The optimal placement of the most sensitive radiated fields from several components has been discovered in this case study, enabling the detection of healthy current flow throughout. Thereafter, the short-circuit investigation, representing faulty situations, is implemented and compared with healthy cases.

This sensing technique can be used for nonintrusive CM of components that are out of reach and cannot have the sensor to be held around it such as components in offshore winds, wind energy generation and power and chemical plants.

The results are provided for three commonly used machines with a single sensor array with numerous settings. The three dimensional (3 D) finite element analysis is applied in the structuring of the sensor, detection of the optimum location and recognition of faults in the machines. Finally, based on the setup design, 3 D printing is used for the construction of the sensor array. Thus, the sensor array with fault detection avoids major component failures and increases system reliability/resiliency.

The purpose of this paper is to discuss results of laboratory tests performed on a point type Faraday magnetic field scanner device designed for monitoring applications.

Automated laboratory setup using a reference magnetic induction source was used to test key parameters such as spatial resolution and signal to noise ratio.

Volume scans of magnitude of the magnetic field induction vector prove applicability of the sensor and demonstrate its advantages.

Sensor is applicable for safe and accurate scanning of the magnetic induction spatial distribution.

The paper presents a novel test setup.

A large number of fastener holes have to be drilled with high quality in the circumferential splice region during the assembly of aircraft fuselage. The purpose of this paper is to design an automatic stepping mechanism for a circumferential splice drilling machine, to meet the requirements of large workspace and high accuracy in drilling at the same time.

A docking position detection method based on magnetic proximity sensors is proposed for the positioning of the arc-shaped rail with respect to the circumferential rails, which significantly improves the accuracy and reliability of automatic stepping. The slipping phenomenon of the end-effector is analyzed, and the optimized counter weights are used to eliminate the slipping and improve the working stability of the stepping mechanism.

An automatic stepping mechanism is developed for the circumferential splice drilling machine, which comprises the docking position detection method and the elimination/suppression method of the end-effector’s slipping.

The proposed automatic stepping mechanism has been integrated into the circumferential splice drilling machine for the fuselage assembly in an aircraft company in China.

An automatic stepping scheme for the circumferential splice drilling machine is proposed, which enhances the efficiency in circumferential splice drilling in aircraft fuselage assembly.

The purpose of this paper is to highlight the increasing use of rotary or angle encoders and examine two distinct types of non‐contact encoders that employ novel technologies to meet the demands of very different applications.

Firstly, examines the design characteristics of optical angle encoders which are used for precision applications such as rotary format computer‐to‐plate pre‐press machines, machine tool A, B and C axes, and surface mount machines. Then considers magnetic encoder design, including the latest OnAxis™ technology for lower cost applications which require less precision, but are often more physically demanding.

Different rotary motion applications demand different combinations of performance and features to optimise their function – some require accuracy, others repeatability, high‐resolution or low‐cyclic error for velocity loop control, plus cost can also be a key consideration.

There is an increasing need to control rotary motion. An appreciation of the design principles of optical angle and rotary magnetic encoders is necessary to ensure that the correct choice of encoder is made for each application. For an angle encoder system, trade‐offs should be made to determine a realistic specification, and whilst many factors can limit achievable accuracy, techniques are available for reducing any shortfall. For applications where cost constraints and lower accuracy specifications demand a magnetic encoder, robust OnAxis™ sensor technology is gaining acceptance amongst designers, and whilst many of the basic design principles of optical encoders still apply, other specific technical aspects, such as much lower resolution and accuracy must be understood before using these devices. Hidden design costs should also be understood such as installation timings and the environmental suitability of magnets.

Will aid designers of rotary motion systems to make a well‐informed selection of encoder type, based on the detailed needs of their applications, including accuracy and cost budgets.

An important segment of the life‐saving functions of higher organisms consists of a distress‐signalling complex. Presents a hypothesis concerning the generic existence of these. Discusses the qualities, activation and function of the signals in connection with different senses and channels against the background of systems theory. Examines a complex of formalized distress signals among animals and analyses various aspects of their reception. Also examines a corresponding man‐made complex with electronic channel augmentation from a national as well as an international point of view. Finally, notes the development of electronic distress signals, incomprehensible to humans.