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The electromechanical planetary transmission system has the advantages of high transmission power and fast running speed, which is one of the important development directions in the future. However, during the operation of the electromechanical planetary transmission system, friction and other factors will lead to an increase in gear temperature and thermal deformation, which will affect the transmission performance of the system, and it is of great significance to study the influence of the temperature effect on the nonlinear dynamics of the electromechanical planetary system.

The effects of temperature change, motor speed, time-varying meshing stiffness, meshing damping ratio and error amplitude on the nonlinear dynamic characteristics of electromechanical planetary systems are studied by using bifurcation diagrams, time-domain diagrams, phase diagrams, Poincaré cross-sectional diagrams, spectra, etc.

The results show that when the temperature rise is less than 70 °C, the system will exhibit chaotic motion. When the motor speed is greater than 900r/min, the system enters a chaotic state. The changes in time-varying meshing stiffness, meshing damping ratio, and error amplitude will also make the system exhibit abundant bifurcation characteristics.

Based on the principle of thermal deformation, taking into account the temperature effect and nonlinear parameters, including time-varying meshing stiffness and tooth side clearance as well as comprehensive errors, a dynamic model of the electromechanical planetary gear system was established.

This paper aims to address some of the needs of present and upcoming rover designs, and introduces novel concepts incorporated in a planetary surface exploration rover design that is currently under development.

The Multitasking Rover (MTR) is a highly re‐configurable system that aims to demonstrate functionality that will cover many of the current and future needs such as rough‐terrain mobility, modularity and upgradeability. lt comprises a surface mobility platform which is highly re‐configurable, which offers centre of mass re‐allocation and rough terrain stability, and also a set of science/tool packs – individual sub‐systems encapsulated in packs which the rover picks up, transports and deploys.

Early testing of the suspension system suggests exceptional performance characteristics.

Principles employed in the design of the MTR can be used in future rover systems to reduce associated mission costs and at the same time provide multiples the functionality.

The electric motor and multi-speed transmission hub are essential components for an electric bicycle. Traditionally, these two devices have been designed and manufactured independently. The purpose of this study is to propose a novel electromechanical device that artfully integrates an exterior-rotor brushless permanent-magnet (BLPM) motor into a transmission hub to become a compact structural assembly.

A novel design that integrates a three-phase, 20-pole/18-slot exterior-rotor BLPM motor with a multi-speed transmission hub composed of a six-link, two-degrees-of-freedom (2-DOF) compound planetary gear train (PGT) is presented in this study to overcome inherent drawbacks of existing designs. An analytical approach, based on fundamental circuits, is developed to synthesize the clutching sequences and numbers of teeth of all gears of the PGT.

The integrated device provides six forward speeds, including two underdrives, two direct drives, and two overdrives, as well as two drive modes: the motor-drive mode and the human-drive mode, for electric bicycles. The main feature of the proposed design is the spur gear teeth merged with the pole shoes of the stator to dramatically minimize the detent torque, which is an oscillatory torque that always induces vibration and acoustic noise of the BLPM motor.

The gear teeth on the pole shoes of the stator provide functions not only for transmission, but also act as dummy slots for adjusting the magnetostatic field of the BLPM motor to effectively reduce the detent torque. The peak value of the detent torque of the integrated design is only 9 percent of the original BLPM motor with identical magnet properties and motor dimensions. Such a feature is contributive in suppressing the vibration and acoustic noise of the electric bicycle's BLPM motor. A BLPM motor rated at 310 W and 250 r/min for the integrated device is presented and analyzed by using the commercial finite-element package Ansoft/Maxwell 2D Field Simulator.

The purpose of this paper is to present a developed modelling method of a car starter with permanent magnet commutator motor.

Mathematical model, algorithm and computational program of electrical and mechanical quantities transients in the system: battery – car starter with permanent magnet commutator motor and planetary gear – combustion engine were developed. Circuit‐field method was applied. Magnetic quantities determined using time‐stepped finite‐element method (with the help of Maxwell software) were used as the parameters of mathematical model equations in circuital part. Program was developed in the Matlab environment.

The developed mathematical model, the algorithm and the program enable the computations of transients of electrical and mechanical quantities at different ambient temperature, by different swept capacity of the combustion engine as well as by different battery capacity and different charge ratio.

The analysis was carried out on an example of four‐cylinder combustion engine. However, the developed modelling method can be used for analysis of different combustion engines start‐up.

The proposed modelling method is useful for analysis of car starters at the stage of design.

The originality of the work consist in the fact that in the developed model variation of the car starter load torque as well as the variations of the entire mechanical system moment of inertia were taken into account.

The purpose of this paper is to resolve the problem of the dynamic response performance of the driving control system for a six-wheeled planetary rover. An adaptive sliding mode controller based on an improved genetic algorithm (IGA) to tune PID sliding surface parameters was used in the driving control system of the planetary rover.

First, the mathematical model of planetary rover driving control is established. Second, according to sliding mode variable structure control, an equivalent controller and a disturbance controller are constructed to solve the problem of a multi-disturbance nonlinear driving control system of planetary rovers and an IGA is used to tune PID parameters.

Simulation results show that the proposed control algorithm improves the accuracy of the driving control system and optimizes the smoothness of rover motion control.

The controller based on the IGA to tune PID sliding surface parameters has good self-adaptability and real-time controllability for the control object which is difficult to present a precise mathematical model.

The advanced control method is adopted to solve the uncertainty and external interference of planetary rovers in a complex environment. The mathematical model of the six-wheeled rover is established as the control object and the uncertainty and external disturbance of the model are considered. The controller based on IGA has good adaptability and real-time performance and the control algorithm can be used to drive robots in complex environments.

The purpose of this paper is to give an overview of the design issues of permanent magnet machines for the hybrid electric and plug‐in electric vehicles, including railway traction and naval propulsion.

Focus is given on both synchronous permanent magnet and reluctance machines. An overview of the design rules are provided, covering the topics of: fractional‐slot windings, fault‐tolerant configurations, flux‐weakening capability, and torque quality.

The peculiarities of these machines and the advanced design considerations to fit the automotive requirements are analyzed.

The paper includes a wide description of innovative electrical machines for electric vehicles, including not only the traction capability, but also analysis of features as weight reduction, torque ripple reduction, increase of fault tolerance, and so on.

Global entrepreneurship may be defined to be the creation of new, value-adding transactions or transaction streams anywhere on the globe. The objective of this chapter is to present and examine a theory of global entrepreneurship. At the World Economic Forum held in Davos, Switzerland, in January 1999, UN Secretary General Kofi Annan called for global entrepreneurship to meet the needs of the disadvantaged and the requirements of future generations. This chapter first presents a transaction cognition theory of global entrepreneurship that is intended as a path for research that responds to this call. Second, this chapter examines the theory from three critical viewpoints: (1) capability for explanation; (2) theoretical and operational utility; and (3) verifiability through the logic of scientific inference, and presents likely propositions that are surfaced by the analysis. Finally in this chapter, some of the likely implications of this theory within the context of globalization are discussed.

The purpose of this paper is to propose an improved method which can shorten the calculation time and improve the calculation efficiency under the premise of ensuring the calculation accuracy for calculating the response of dynamic systems with periodic time-varying characteristics.

An improved method is proposed based on Runge–Kutta method according to the composition characteristics of the state space matrix and the external load vector formed by the reduction of the dynamic equation of the periodic time-varying system. The recursive scheme of the holistic matrix of the system using the Runge–Kutta method is improved to be the sub-block matrix that is divided into the upper and lower parts to reduce the calculation steps and the occupied computer memory.

The calculation time consumption is reduced to a certain extent about 10–35% by changing the synthesis method of the time-varying matrix of the dynamics system, and the method proposed of paper consumes 43–75% less calculation time in total than the original Runge–Kutta method without affecting the calculation accuracy. When the ode45 command that implements the Runge–Kutta method in the MATLAB software used to solve the system dynamics equation include the time variable which cannot provide its specific analytic function form, so the time variable value corresponding to the solution time needs to be determined by the interpolation method, which causes the calculation efficiency of the ode45 command to be substantially reduced.

The proposed method can be applied to solve dynamic systems with periodic time-varying characteristics, and can consume less calculation time than the original Runge–Kutta method without affecting the calculation accuracy, especially the superiority of the improved method of this paper can be better demonstrated when the degree of freedom of the periodic time-varying dynamics system is greater.

This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.

Standardized systems for feeding, gripping, and joining are needed to realize the potential of microsystem and nano‐system technology. This paper describes many several systems that are operating in this area and the applications for the new technology and the parts that can currently be manufactured. These include miniature pneumatic valves, matchstick sized motors and fluidic pumps.