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The purpose of the control method proposed in this paper is to address the problem of the poor anti-interference of the suspension winding current in the traditional bearingless induction motor (BL-IM) direct suspension force control process.

A model predictive direct suspension force control of a BL-IM based on sliding mode observer is proposed in this paper. The model predictive control (MPC) is introduced to the traditional direct suspension force control to improve the anti-interference of the suspension current. A sliding mode flux linkage observer is designed and applied to the MPC system, which reduces the error of the parameter observation and improves the robustness of the system. The strategy is designed and implemented in the MATLAB/Simulink and the two-level AC speed regulation platform.

The simulation and experimental results show that the performance of the BL-IM under the control method proposed in this paper is better than that under the traditional direct suspension force control, and the suspension performance of the motor and the anti-interference of the control system are improved.

This study helps to improve the suspension performance of the motor and the anti-interference of the control system.

The object of this research is the reconstruction of the existing legal response by European Union states to the phenomenon of immigration. It seeks to analyse the process of conferral of protection.

One main dimension is selected and discussed: the case law of the national courts. The study focuses on the legal status of immigrants resulting from the intervention of these national courts.

The research shows that although the courts have conferred an increasing protection on immigrants, this has not challenged the fundamental principle of the sovereignty of the states to decide, according to their discretionary prerogatives, which immigrants are allowed to enter and stay in their territories. Notwithstanding the differences in the general constitutional and legal structures, the research also shows that the courts of the three countries considered – France, Germany and Spain – have progressively moved towards converging solutions in protecting immigrants.

The research contributes to a better understanding of the different legal orders analysed.

Knight's Industrial Law Reports goes into a new style and format as Managerial Law This issue of KILR is restyled Managerial Law and it now appears on a continuous updating basis rather than as a monthly routine affair.

The Equal Pay Act 1970 (which came into operation on 29 December 1975) provides for an “equality clause” to be written into all contracts of employment. S.1(2) (a) of the 1970 Act (which has been amended by the Sex Discrimination Act 1975) provides:

The Howard Shuttering Contractors case throws considerable light on the importance which the tribunals attach to warnings before dismissing an employee. In this case the tribunal took great pains to interpret the intention of the parties to the different site agreements, and it came to the conclusion that the agreed procedure was not followed. One other matter, which must be particularly noted by employers, is that where a final warning is required, this final warning must be “a warning”, and not the actual dismissal. So that where, for example, three warnings are to be given, the third must be a “warning”. It is after the employee has misconducted himself thereafter that the employer may dismiss.

Presents the manipulation methods of a low powered direct‐drive robot‐arm for heavy object manipulation using a suspension device. Considers manipulation of a suspended tool in the horizontal plane. Presents the algorithm of the hybrid position/force tracking scheme with respect to the dynamic behavior of suspended tools in the horizontal plane. To manipulate the suspended robot‐arm vertically, the hybrid position/force dynamic model has been developed by considering the gravity compensation of the spring balancer. In order to show the possible industrial applications chamfering operations have been carried out. Simulations and experiments demonstrate the feasibility of the proposed systems.

This paper aims to design a PD controller for an active suspension system to improve the car’s moving smoothness.

The controller parameters are optimized by an in-loop genetic algorithm (iL-GA). Unlike previous studies that only used conventional GAs to tune coefficients for the controller, the iL-GA designed in this paper provides outstanding efficiency when determining the optimal value range for the system. The optimal value range of parameters is determined by the in-loop algorithm based on criteria related to systematic errors. The optimal values are then calculated by the GA based on this range instead of an uncertain one.

Simulation results show that vehicle body acceleration and displacement values are significantly reduced when using the active suspension system compared to the conventional passive suspension system. The phase difference phenomenon does not occur in the iL-GA situation. In addition, the frequency domain investigation also shows the system’s stability when using iL-GA instead of conventional GA.

To the best of the authors’ knowledge, this is a new application that provides positive effects to the suspension controller. This algorithm can be applied to tune coefficients for direct controllers in the future.

Series elastic actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series elastic actuators employ a novel mechanical design architecture which goes against the common machine design principal of “stiffer is better”. A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke’s Law (F = Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions.

The purpose of this paper is to evaluate the locomotion performance of all‐terrain rovers employing rocker‐type suspension system.

In this paper, a robot with advanced mobility features is presented and its locomotion performance is evaluated, following an analytical approach via extensive simulations. The vehicle features an independently controlled four‐wheel‐drive/4‐wheel‐steer architecture and it also employs a passive rocker‐type suspension system that improves the ability to traverse uneven terrain. An overview of modeling techniques for rover‐like vehicles is introduced. First, a method for formulating a kinematic model of an articulated vehicle is presented. Next, a method for expressing a quasi‐static model of forces acting on the robot is described. A modified rocker‐type suspension is also proposed that enables wheel camber change, allowing each wheel to keep an upright posture as the suspension conforms to ground unevenness.

The proposed models can be used to assess the locomotion performance of a mobile robot on rough‐terrain for design, control and path planning purposes. The advantage of the rocker‐type suspension over conventional spring‐type counterparts is demonstrated. The variable camber suspension is shown to be effective in improving a robot's traction and climbing ability.

The paper can be of great value when studying and optimizing the locomotion performance of mobile robots on rough terrain. These models can be used as a basis for advanced design, control and motion planning.

The paper describes an analytical approach for the study of the mobility characteristics of vehicles endowed with articulated suspension systems. A variable camber mechanism is also presented.