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The purpose of this paper is to develop a theoretical design for the attitude control of electromagnetic formation flying (EMFF) satellites, present a nonlinear controller for the relative translational control of EMFF satellites and propose a novel method for the allocation of electromagnetic dipoles.

The feedback attitude control law, magnetic unloading algorithm and large angle manoeuvre algorithm are presented. Then, a terminal sliding mode controller for the relative translation control is put forward and the convergence is proved. Finally, the control allocation problem of electromagnetic dipoles is formulated as an optimization issue, and a hybrid particle swarm optimization (PSO) – sequential quadratic programming (SQP) algorithm to optimize the free dipoles. Three numerical simulations are carried out and results are compared.

The proposed attitude controller is effective for the sun-tracking process of EMFF satellites, and the magnetic unloading algorithm is valid. The formation-keeping scenario simulation demonstrates the effectiveness of the terminal sliding model controller and electromagnetic dipole calculation method.

The proposed method can be applied to solve the attitude and relative translation control problem of EMFF satellites in low earth orbits.

The paper analyses the attitude control problem of EMFF satellites systematically and proposes an innovative way for relative translational control and electromagnetic dipole allocation.

The HITSAT‐1 is the first small satellite developed by Harbin Institute of Technology (HIT) whose mission objective is to test several pivotal techniques. In the initial orbit period, the satellite is likely to tumble as the result of separating from the rocket. How to capture it promptly with finite magnetic torque is an important problem. In this paper, considering the restrictive conditions of the magnetic field, the variable structure control theory is used to cope with the magnetic torque. Because of using the reaction wheels and magnetorquers as the control actuators, the combination control algorithm has been adopted in the initial orbit period. The results of the computer simulation indicated that the algorithm has excellent robustness and can be designed and realized easily.

The paper presents the results of work on control systems of bearingless electric motors. Authors proposed the applications of bearingless electric machines for aircraft actuation system. Suggested solution characterizes novel concept of on-board equipment design such as More Electric Aircraft. Magnetic suspension technology allows elimination of friction force and the negative performance features of classic bearing system. However, to achieve all these purposes appropriately, dedicated control system must be also applied.

The development of a control system of bearingless electric machine is presented in detail. Mathematical model and construction of induction bearingless motor are widely discussed. Then, proportional–integral-derivative controller algorithm designing for BEM control system was presented using the well pole placement method. Simulation model of BEM control system with use of Matlab-Simulink software was shown. Finally, experimental studies on laboratory stand were introduced. The paper presents design methodology of conventional and advanced control system of bearingless motor.

The presented concept of the bearingless electric machines could be applied in the on-board actuation system. During research, full control system of bearingless electric motor was designed and tested. This system consisted of two subsystems. The first responded for rotary speed stabilization and second one was designed for position control of the rotor in the air gap.

The presented concept of the bearingless electric machines could be applied in the on-board actuation system. During research, full control system of bearingless electric motor was designed and tested. This system consisted of two subsystems. The first responded for rotary speed stabilization and second one was designed for position control of the rotor in the air gap.

The idea of active magnetic suspension system will be implemented for aviation on technology readiness level V. The paper presents unique laboratory stand with bearingless electric motor and experimental studies. The stable time responses of designed control system were presented and discussed. In addition, preliminary considerations of advanced control system with robust controller were introduced as well.

The purpose of this paper is to investigate the problem of the initial attitude detumbling and acquisition for micro‐satellite using geomagnetism with the aid of the pitch momentum bias, and the application of the feedback linearization method, H_∞ and μ‐synthesize control theory in the robust attitude acquisition controller design.

The pitch flywheels establish the momentum bias state in the beginning of the detumbling stage and keep the momentum bias state thereafter. The geomagnetic change rate feedback detumbling controller is used to detumble the micro‐satellite and the gyroscope rigidity is utilized to capture orbital negative normal orientation in the detumbling and attitude acquisition phase. Feedback linearization method is adopted to obtain the linear attitude dynamics. Based on the feedback linearization model, a quasi proportion differential (PD) controller is designed, meanwhile H_∞ and μ‐synthesis control theories are adopted to synthesis the robust attitude acquisition controllers.

The pitch momentum bias‐aided attitude detumbling and acquisition method make the capture of the orbital negative normal orientation faster and more accurate than the classical initial operation process. Quasi PD and H_∞ have greater robustness than the classical PD attitude acquisition controller in normal geomagnetic case; quasi PD and μ‐synthesis have greater robustness than the classical PD attitude acquisition controller in magnetic storm case.

Provides pitch momentum bias‐aided attitude detumbling and acquisition method for the micro‐satellite and the robust attitude acquisition controller design technology.

Recent advances in nano and picosatellite missions and future such missions require three axis attitude control system hardware for attitude control purposes. A simple, cost effective, yet an efficient devise that is used for active attitude control is magnetic torquer coil. The purpose of this paper is to describe the design and fabrication of a template to manufacture magnetic torquer coils of varying sizes and shapes.

Details about the development of the template design, analysis, and fabrication are discussed. The development status of the system is outlined and the working prototype of the device is described and some preliminary test results are given.

A fully functional prototype of the template has been developed and testing has been conducted that demonstrated the effectiveness of the device. Magnetic torquer coils of varying sizes were fabricated and tested. A finite element analysis was performed by modeling the characteristics of the fabricated coils to determine thermally induced stresses and deformations during its space operations.

The paper illustrates and demonstrates an effective application of torquer coil template in the satellite fabrication industry. The benefits from the approach are generally applicable to any future university and industry missions using picosatellite technology.

The designed template satisfied all the constraints and requirements. Furthermore, its advantages include scalability, modularity, and its capability to fabricate magnetic torquer coils of varying sizes and shapes.

The stability and input voltage saturation is a common problem associated with an active magnetic bearing (AMB) system. The purpose of this paper is to design a control scheme that stabilizes the single degree of freedom AMB system and also tackle the problem of input voltage saturation in the AMB system.

The proposed control technique is a combination of two separate control schemes. First, the Backstepping control scheme is designed to stabilize and control the AMB system and then Chebyshev neural network (CNN)-based compensator is designed to tackle the input voltage saturation when the system control action is saturated.

The mathematical and simulation results are presented to validate the effectiveness of proposed methodology for single-degree freedom AMB system.

This paper introduces a CNN-based compensator with Backstepping control strategy to stabilize and tackle the problem of input voltage saturation in the 1-DOF AMB systems.

In this paper, we present a method to take into account the feedback control in software developed from coupled field circuit models. The implementation of control loops is done in a software which is able to simulate electromagnetic devices associated with power electronic circuits having a time dependent topology. The control strategy is implemented in a discrete‐time version and can manage all controllable electronic switches by means of different electric or magnetic quantities calculated during the simulation (flux, currents, voltages, …). Electrical systems involving magnetic devices, power electronic converters and their control devices can be simulated in presence of phenomena such as eddy currents or saturation of the magnetic materials.

The purpose of this paper is to discuss a new method of iron loss estimation under pulse width modulation (PWM) converter supply. The proposed method concerns the longitudinal magnetisation.

A novel method of iron loss estimation applies values of iron losses that come from a single higher harmonic coexisting with a DC‐bias field. This method considers non‐linearity of ferromagnetic. Results of estimation are validated using experimental results.

The paper formulates that the dependence of iron losses come from harmonics, on DC‐bias field. Moreover, it formulates possibilities of their utilization to iron loss estimation in case of deformed flux. On the other hand, it discusses the influence of DC‐bias field on static hysteresis and classical eddy current losses.

Experimental verification will still be needed as to the accuracy of the proposed model and applicability to various magnetic materials.

The paper provides an easy mathematical method of iron loss estimation, under PWM voltage supply.

The paper explains how to use an analytical method and results of iron losses come from single harmonics, obtained under coexistence with DC‐bias field, to iron loss estimation in case of longitudinal magnetisation where deformed magnetic flux occurs.

The purpose of this paper is to propose an attitude determination and control scheme for a low‐cost Micro‐satellite with defective inertia. Restricted by the payload design, the z‐axis inertia of this satellite is larger than the x and y axes, which is unstable for natural attitude dynamics.

An original operation mode is designed to avoid z axis from long‐time pointing to the sun during damping, which avoids some unexpected damage. In attitude determination design, EKF and UKF algorithms are compared on estimation accuracy, convergence time and computation complexity in attitude estimation design, which is referred to determine the final estimation scheme. A DSP‐based hardware solution is achieved and a semi‐physical testing and simulation system is built.

Simulation results show the 3‐axis stable mode can be built with the proposed scheme, and the unprotected facet of the satellite can be kept away from long‐time pointing to the sun.

The proposed ADCS scheme can be a reference for the future Micro‐satellite programs which share the similar configuration.

A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of the service period of the cutting tool while machining. It is significant to provide a corresponding real-time varying damping to control this chatter, which directly influences accuracy and quality of productivity. This paper aims to review the literature related to the application of smart fluid to control vibration in metal cutting and also focused on the challenges involved in the implementation of active control system during machining process.

Smart dampers, which are used as semi-active and active dampers in metal cutting, were reviewed and the research studies carried out in the field of the magnetorheological (MR) damper were concentrated. In smart materials, MR fluids possess some disadvantages because of their sedimentation of iron particles, leakage and slow response time. To overcome these drawbacks, new MR materials such as MR foam, MR elastomers, MR gels and MR plastomers have been recommended and suggested. This review intents to throw light into available literature which exclusively deals with controlling chatter in metal cutting with the help of MR damping methods.

Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. In the past, many researchers have attempted to implement MR damper in metal cutting to control vibration and were successful. Various methods with the help of MR fluid are illustrated.

A new cutting tool is always well-defined and sharp at the onset of metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of service period of cutting tool while machining. Application of MR damper along with the working methodology in metal cutting is presented, challenges met are analyzed and a scope for development is reviewed.

This study provides corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity. Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration.

This study attempts to implement smart damper in metal cutting to control vibrations.

It is significant to provide corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity.