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The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.

A novel magnetic nutation drive is proposed, and the structure and principle of the designed magnetic nutation drive are described in this study. Three-dimensional finite element analysis is used to compute the magnetic and torque of the magnetic nutation drive. Furthermore, a prototype of this novel magnetic nutation drive device is developed with 3D printing technology and tested to verify the feasibility of the proposed structure and principle.

The simulation and experimental results indicated that the proposed magnetic nutation drive device could meet the desired specifications, and that this novel magnetic nutation drive device successfully realized the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.

This novel magnetic nutation drive is low-cost and easy to make and use, and which provides the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.

For the first time, this research applies the permanent magnet drive technology to nutation drive and puts forward a new non-contact nutation drive mode. The novel drive mode can solve some problems of the traditional mechanical contact nutation drive, such as vibration, friction loss, mechanical fatigue and necessity of lubrication. The proposed non-contact nutation drive device can achieve a high reduction ratio with compact structure and can be suitable for industry application.

MODERN turbojet engines have a shaft speed range of approximately 2 to 1 (from ground idle to take‐off) and it is necessary, therefore, to have some form of infinitely‐variable‐ratio gearbox to obtain a constant speed for accessories such as a.c. generators. Various means of doing this are available; for example, these could be mechanical, electrical, hydraulic or pneumatic, or a combination of these. The purpose of this paper is to discuss the major types of constant speed drive (C.S.D.) that have been evolved, mentioning the design problems associated with each.

This paper aims to consider main challenges of development of advanced architectures of propulsion systems, i.e. distributed propulsion systems (DPS).

This paper is a comparative analysis of different types of DPS.

Mechanical driving DPS seems as more feasible in near-term outlook, and turboelectric and full electric DPS are imagined feasible in mid- and far-term outlook.

Additional comprehensive numerical and experimental researches are needed to approve the efficiency of DPS.

Possible impact of installation of DPS on aeroplane fuel efficiency are shown.

Application of DPS on long-range aeroplanes is new a engineering solution, which may allow to meet future advanced efficiency goals.

Retracting mechanisms may be operated either manually or by power systems, according to the type and size of aircraft. Manual systems may be classified into two main groups, mechanical and hydraulic. The mechanical group may be further sub‐divided according to the form of mechanism; e.g., cable and pulley, screw and nut, worm and other gears, all of which have been used for retraction schemes at some time or another. Power systems are even more diverse, many of them being of recent birth and, therefore, still in the experimental stage. Some of the various ways in which power can be applied to drive the retracting mechanism are by: electric motor and mechanical coupling; electric motor and hydraulic pump; aero engine coupling to hydraulic pump; compressed air motor and hydraulic pump; and other pneumatic systems.

Examines the central proposition that the marketing‐purchasing of new industrial manufacturing technologies involves the development (not necessarily a planned design) of a new network of relationships within and across enterprises. Presents the results of a detailed case study on the adoption by manufacturers of a new technology, electric motor drives, to illustrate research on new‐technology network anatomy. The results include additional evidence to the work of Wim G. Biemans on the importance of research on lateral relationships in testing and gaining approval for transforming an enterprise from an old to a proven, better, new manufacturing technology.

A method for calculating the displacement of a moving armature and additional masses in an electromagnetic device is presented. The transient magnetic field is calculated numerically, considering the velocity and the nonlinearity of iron. The resulting force drives a mechanical system described by the equation of motion, which is solved by a Runge‐Kutta‐algorithm If more than one part of the device is moving, the conservation of momentum is taken into account to determine the movement. Four methods to shorten the calculation time and keep or improve the accuracy in determination of displacement and velocity are investigated. One of these methods leads, in spite of a shortened calculation time, to better results.

The purpose of this paper is to elaborate a robust model‐based protective control algorithm for multi‐mass motor drives that are subjected to physical and safety constraints on their variables.

The algorithm relies on the off‐line computed maximum robust controlled invariant set or its approximation for the given drive system and imposed constraints. It can be used to patch any existing drive control scheme with a firm constraints satisfaction guarantee. The online patch implementation is actually a simple correction of the control signal computed with the existing control scheme, with a mandatory state observer.

Performance of the patch is tested on a two‐mass drive system in combination with classical two‐mass drive speed controllers – P+I and reduced state controller. All constraints violations that exist in the presented responses obtained without the protection patch are suppressed by using the patch which shows the effectiveness of the approach. A brief implementation analysis shows that a digital signal processor could be used for online implementation of the controller with the protective patch.

Robust invariant sets theory is efficiently and effectively used in a new application area – protection of multi‐mass electrical drives.

One of the interesting characteristics of British life is the way that various groups in society view each other's roles. How often have we heard people in business described as shrewd and hard, people in the academic world described as idealistic and intellectual, and people in the arts described as aesthetic and emotional. Of course, the unrealistic impression created by such generalisations is that few have the ability to operate in the other's domain or even share in each other's work. Such a criticism is often levelled at those of us in education as if we were unaware of the need to examine other people's roles.

This paper aims to improve the meshing effect of the gear teeth. It is recommended to analyze the deformation difference between the inner and outer surfaces of the flexspline. The purpose of this paper is to modify the profile of the flexspline based on the deformation difference to improve the transmission accuracy and operating life of the harmonic drive.

In this paper, ring theory is used to calculate the deformation difference of the inner and outer surfaces of the flexspline, and the actual tooth profile of the flexspline is corrected based on the deformation difference. Then, the flexspline is divided into multiple sections along the axial direction, so that the three-dimensional tooth profile of the flexspline is modified to improve the gear tooth meshing effect.

This paper proves the effect of the deformation difference between the inner and outer surfaces of the flexspline on the tooth backlash, which affects the transmission accuracy and life of the harmonic drive. It is recommended to modify the tooth profile of the flexspline based on the deformation difference, so as to ensure the tooth meshing effect.

This paper provides a new way for the optimization of the three-dimensional tooth profile design of the harmonic drive.