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An electromechanical converter supplied with the special feed systems which accelerate its operation in transient states is investigated. To solve the problem the field‐circuit procedure is applied. The transients in an axisymmetric plunger‐type actuator with conducting core, after the application of supply voltage, taking the movement of some core parts into account are considered. The converter winding is composed of two coils connected with a system of external elements: resistors, capacitors and transistors.

The purpose of this paper is to elaborate algorithm and software for the optimization of the actuator–capacitor system taking the dynamics parameters into account. The system is applied for driving the valve of plasma gun. Two optimization strategies are proposed and pondered. The penalty function approach has been expanded in detail.

The field-circuit mathematical model of the dynamics operation consists of the strongly coupled equations of the transient electromagnetic fields and the equations of the electric circuit. The numerical implementation is based on finite element method and step-by-step Cranck–Nicholson procedure. The genetic algorithm has been used in the optimization procedure. The sigmoidal transformation has been applied to adjust the classical external penalty function method to the genetic algorithm.

The modification consists in adaptation of the penalty function to the genetic algorithm. In the proposed approach, operations involving successive iterations of increasing penalty function and operations containing genetic iterations are intertwined with each other. The differences between these two procedures are getting blurred. The proposed approach is very effective. It is possible to achieve optimal solution even more than ten times faster than using the classical method.

The proposed approach can be successfully applied to designing and optimization of different electromagnetic devices, including functional constraints.

The fast and flexible development of fast switching electromagnetic valves as used in modern gasoline engine demands the availability of efficient and accurate simulation tools. The purpose of this paper is to provide an enhanced computational scheme of these actuators including all relevant physical effects of magneto‐mechanical systems and including contact mechanics.

The finite element (FE) method is applied to efficiently solve the arising coupled system of partial differential equations describing magneto‐mechanical systems. The algorithm for contact mechanics is based on the cross‐constraint method using an energy‐ and momentum‐conserving time‐discretisation scheme. Although solving separately for the electromagnetic and mechanical system, a strong coupling is ensured within each time step by an iterative process with stopping criterion.

The numerical simulations of the full switching cycle of an electromagnetic direct injection valve, including the bouncing during the closing state, are just feasible with an enhanced and robust mechanical contact algorithm. Furthermore, the solution of the nonlinear electromagnetic and mechanical equations needs a Newton scheme with a line search scheme for the relaxation of the step size.

The paper provides a numerical simulation scheme based on the FE method, which includes all relevant physical effects in magneto‐mechanical systems, and which is robust even for long‐term contact periods with multitude re‐opening phases.

There are two commercially accepted methods of force control used in automated surface finishing today. The first method, “through‐the‐arm” force control, applies force using the position of all the robot axes in unison. The second method, “around‐the‐arm” force control, uses the robot for positioning motion only, and applies a controlled force through an auxiliary‐compliant end‐of‐arm tool. Discusses the theory, applicability and features of each of these two technologies.

This paper aims to design and control of a novel compact transportation system called the “wearable vehicle”. The wearable vehicle allows for traversing all types of terrains while transporting one's luggage in a comfortable and efficient manner.

The proposed design consists of a lower limb exoskeleton carrying two motorized wheels and two free wheels installed alongside its feet. This paper presents a detailed description of the system with its preliminary design and finite element analysis. Moreover, the system has been optimally designed to decrease wearable vehicle’s total weight, consequently leading to a reduction in motor size. Finally, two controllers have been designed to achieve stable operation of the wearable vehicle while walking. A PD controller with gravity compensation has been designed to ensure that the wearable vehicle tracks human motion, while a PID controller has been designed to ensure that the zero moment point is close to the center of the system’s support polygon.

Experimental tests were carried out to check the wearable vehicle concept. The obtained results prove the feasibility of the proposed wearable vehicle from the design, dynamics and control viewpoints.

This proposed wearable vehicle’s purpose is for traveling faster with less effort than normal walking. When a human comes across a flat open ground, the wearable vehicle can be used as a vehicle. However, when a human enters crowded traffic, an unstructured area or other obstacles like stairs, the vehicle can be switched into walking mode.

The wearable vehicle has seven DOFs exoskeletons, two motorized wheels, two free wheels and a foldable seat. It is used as a vehicle via its motorized and free wheels to travel fast with minimal effort. In addition, the human can switch easily into walking mode, if there is unstructured terrain to be traversed. Furthermore, an illustration of system's mechanisms and main feature parameters are presented to become acquainted with the ultimate benefits of the new system.

A new, non‐explosive actuator (NEA) developed by G&H Technology holds tensile loads of up to 12,500lb and quickly releases them when electronically activated. The Model 1203 actuator is stated to be safe, fast‐acting and highly reliable, and release occurs with minimum shock. The actuator is ideal for a wide range of remote actuation requirements such as those found in space, launch vehicle, downhole drilling, undersea and nuclear power applications.

This paper presents a 2D nonlinear magnetomechanical analysis of an electromagnetic actuator based on finite elements. An impact mechanical problem with its inherent convergence problems has to be solved inside the magnetic field region. Beside material and geometric nonlinearities also dynamic effects like eddy currents are considered.

This paper aims to present a state-of-the-art review in various fields of interest, leading to a new concept of bio-inspired control of small aircraft. The main goal is to improve controllability and safety in flying at low speeds.

The review part of the paper gives an overview of artificial and natural flow sensors and haptic feedback actuators and applications. This background leads to a discussion part where the topics are synthesized and the trend in control of small aircraft is estimated.

The gap in recent aircraft control is identified in the pilot–aircraft interaction. A pilot’s sensory load is discussed and several recommendations for improved control system architecture are laid out in the paper.

The paper points out an opportunity for a following research of suggested bio-inspired aircraft control. The control is based on the artificial feeling of aerodynamic forces acting on a wing by means of haptic feedback.

The paper merges two research fields – aircraft control and human–machine interaction. This combination reveals new possibilities of aircraft control.

An overview is given on design features, numerical modelling and testing of a novel electromagnetic actuator to achieve a controllable stiffness to be used as a device for parametric stiffness excitation.

In principle, the actuator consists of a current driven coil placed between two permanent magnets. Repellent forces are generated between the coil and the magnets, centering the coil between the two magnets. The 2D finite element analyses are carried out to predict the forces generated by this arrangement depending on coil current and coil position. Force measurements are also made using the actual device.

Actuator forces as predicted by the finite element analyses are in excellent agreement with the measured data, confirming the validity of the numerical model. Stiffness of the actuator is defined as the increase of force per unit of coil displacement. Actuator stiffness depends linearly on the coil current but in a nonlinear manner on the coil displacement. The performance of the actuator is sufficient to demonstrate the effect of a so‐called parametric anti‐resonance on a test stand.

Although the performance of the actuator is satisfactory, there is potential for further improvement of the actuator design.

This paper reports for the first time on an electromechanical device to create a time‐periodic stiffness variation to be used for research in the field of parametrically excited mechanical systems. The device is used to prove experimentally an effect to suppress mechanical vibrations which has been studied so far only in theoretical studies.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.