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Mechanical elastic wheel (MEW) has the advantage of explosion-proof, which helps to guarantee the safety and maneuverability of the automobile. Aiming to improve the stability of vehicles matching with MEW, this paper proposes an integrated control strategy that combines the active front steering and the active suspension systems. The integrated controller consists of feed-forward and feedback controllers. Firstly, the differential flatness system of the vehicle is constructed concerning the coupling among yaw, lateral, and roll motion. And the flatness based feed-forward control inputs of the desired front wheel angle and active roll moment are derived. At the same time, the backstepping-adaptive feedback controllers for yaw rate and roll angle are designed. Then, the feed-forward and feedback controllers are coordinated and their weight coefficients are adjusted according to the sideslip angle. Furthermore, this paper also adopts a nonlinear disturbance observer to estimate the vertical load of MEW. The influence of the vertical load is fully considered when estimating the equivalent cornering stiffness of each MEW, so as to realize the online adjustment of the controller parameters. Finally, the maneuver tests of step input steering and double lane change are simulated, respectively. The results show that the proposed control strategy yields a better control effect than the fuzzy-PID controller, and the performance of the vehicle matching with MEW has been significantly improved. [ABSTRACT FROM AUTHOR]

In this article, a pyramid-type single-gimbal control moment gyro system mounted on a space structure is employed to realize the integrated control of singularity avoidance attitude maneuver and vibration suppression. The rest-to-rest attitude maneuver is divided into three sections, in which null motion is applied to achieve the above two objects leading to a better control performance. The effectiveness of the proposed control strategy is verified using numerical simulation examples. [ABSTRACT FROM AUTHOR]

A study pointed out that the delay time of the driver’s nervous system has a significant effect on the roll stability of the vehicle. However, the existing researches on vehicle rollover prevention control rarely consider the influence of driver factors on vehicle roll stability. Aiming at this problem, a vehicle roll stability and path tracking control strategy considering driver in the loop is proposed to assist different types of drivers. It includes the supervisory decision layer and execution layer. The supervisory decision layer selects the corresponding control mode according to the driver’s steering wheel angle change rate, path tracking deviation and vehicle roll stability information. The execution layer includes three modes: human-machine shared steering, active braking and integrated chassis control. The human-machine shared steering and active braking modes assist the driver to improve the roll stability and path tracking accuracy. The integrated chassis control mode is used for the automatic driving of vehicles under emergency conditions. Simulation results show that the proposed control strategy can effectively improve the vehicle roll stability and path tracking accuracy, and reduce the driver’s operating burden.

In the optimization of mixed urban and freeway networks, most existing control strategies implement centralized controllers that are not appropriate for real-time control in large-scale traffic networks due to the huge computational complexity. In this article, a distributed control framework for the cooperative control of mixed urban and freeway traffic networks is developed. First, an integrated traffic model is presented to characterize the interactions between the urban and freeway networks. In addition, a partitioning method is proposed, and then, the mixed traffic network is divided among urban agents and freeway agents for the easy implementation of the distributed control framework. The optimization problem of the whole network can then be decomposed into a number of suboptimization problems based on the partition of the network. In the proposed distributed control strategy, each agent solves its own optimization problem independently with local information and transmitted information from neighboring agents to seek the Nash equilibrium. Finally, the computational efficiency and the effectiveness of the distributed integrated control strategy of mixed traffic networks are evaluated through a numerical example. [ABSTRACT FROM AUTHOR]

For long-pulse tokamaks, one of the main challenges in the control strategy is to simultaneously reach multiple control objectives and to robustly handle in real-time (RT) unexpected events [off-normal-events (ONEs)] with a limited set of actuators. We have developed in our previous work a generic architecture of the plasma control system to deal with these issues. Due to this generic feature, we are able to extend it with an advanced supervisor: Supervisory control and Actuator Management with ONEs (SAMONE) to deal with multiple ONEs and multiple control scenarios in this work. We first standardize the evaluation of ONEs and, thereby, simplify significantly the supervisor decision logic, as well as facilitate the modifications and extensions of ONE states in the future. Then, we present the recent developments of real-time decision-making by the supervisor to switch between different control scenarios (normal, backup, shutdown, disruption mitigation, and so on) during the discharge based on ONE states. The developed SAMONE has been implemented on the TCV tokamak, applied to disruption avoidance with density limit experiments, demonstrating the excellent capabilities of the new RT integrated strategy. [ABSTRACT FROM AUTHOR]

This article presents a Takagi–Sugeno (T–S) fuzzy-based robust H∞ integrated lane-keeping (LKS) and direct yaw moment control (DYC) system to improve the automatic driving performance of unmanned electric vehicles. First, a T–S fuzzy lateral model of unmanned electric vehicles is constructed, in which the cornering stiffness uncertainties, external disturbance, time varying look-ahead distance, and longitudinal velocity are considered. Second, an integrated LKS and DYC control system of unmanned electric vehicles is constructed to handle the time-varying features, parametric uncertainties, and overactuated actuators of unmanned electric vehicles, in which a T–S fuzzy-based robust H∞ output feedback control law is designed to produce the desired front wheel steering angle and external yaw moment, and a dynamic quadratic programming distribution law is presented to allocate the desired external yaw moment of unmanned electric vehicles. Finally, the simulation and experimental results are implemented to verify the availability of the proposed control scheme. [ABSTRACT FROM AUTHOR]

This paper investigates the front-wheel differential steering system (DSS) for a four-wheel independent-drive (4WID) electric vehicle (EV) with a steer-by-wire (SBW) system in case of the steering failure. The nonlinear dynamic model of differential steering vehicle (DSV) is established and the stability regions at different adhesion coefficients are determined based on the theory of phase plane. The traditional front-wheel steering vehicle is selected as the reference model. The direct yaw moment control (DYC) aiming to restore the vehicle to the stability region, and the DSS control aiming to achieve the normal steering function based on the theory of model reference sliding mode control, are researched and applied to the nonlinear dynamic model successively. The direct yaw moment and differential driving torque of the front-wheel needed for the vehicle stability and DSS are obtained respectively. The simulation results show that the proposed integrated control can simultaneously ensure the differential steering and vehicle stability of the nonlinear vehicle on different adhesion coefficient roads.

In this paper, the wireless power transfer (WPT) system with dynamic loads such as batteries is studied comprehensively. An integrated control technology of load estimation and power tracking of LCC compensated is proposed, which realizes load estimation, mode judgment and charging control at the transmitter, and standard load setting and decoupling control at the receiver. Based on the influence of reflection impedance on the output current of the inverter, a method of identifying coupling coefficient and equivalent load is proposed and a mathematical model is established. Receiver controller provides standard reference load for load estimation. Transmitter controller judges battery status according to the estimation of equivalent load and adopts double closed-loop control to regulate power and current. Receiver decouples control when battery charging voltage reaches the threshold, and providing mode conversion sign for transmitter controller to realize constant current (CC) and constant voltage (CV) charging of battery. The Dual-sides integrated control scheme has no data communication between transmitter and receiver, so it can control independently, which reduces the complexity of the system and is suitable for different charging modes. The proposed controller is more efficient as it maintains a track current, and dynamically alters the pick-up characteristics to suit the load demand. Finally, the simulation and experimental results validate the feasibility of proposed control method, which realizes the estimation of the load and CC/CV charging of the battery. The proposed WPT system achieved the efficiency at 91.16% while delivering 2kW to the load with a vertical air gap of 150mm.

An integrated control system developed for improving the vehicle handling and stability under critical lateral motions that includes electric-stability-controller (ESC) and rear-wheel-active-steering (RAS) systems and coordinates the ESC and RAS controllers based on the β-β̇ phase plane method is discussed in this paper. The ESC includes a fuzzy logical controller that calculates the yaw moment and an additional rear wheel steering angle based on the vehicle steering states. The RAS control system consists of two parts: a feedback controller and a feed-forward controller. When the vehicle in the normal driving situations, the RAS system provides enhanced handling performance. If the vehicle reaches its handling limits, then both ESC and RAS are integrated to ensure vehicle stability. The simulation results demonstrated that the proposed integrated controller system not only can resist external interference and reduce driver fatigue but also improves both vehicle stability and handling.

In this article, the presented work proposes a power management scheme in a dc microgrid by utilizing integrated device level control designs. Dynamics of nondispatchable energy sources, energy storage systems, and critical loads while synthesizing the control scheme are extensively studied. The presented work focuses on the integrated operation of local converter controls and power control unit during load fluctuations, environmental changes, accidental islanding, state of charge (SOC) breach, etc., without any time-critical information sharing. Low bandwidth communication (LBC) assisted control actions are enabled only in response to specific events such as battery management system (BMS) operation in autonomy, onset of peak hours, and load shedding. This article examines small signal analysis of individual interfacing converters to conduct eigenvalue studies of the closed-loop control systems. Successful control transitions are achieved in real-time digital simulator to validate the proposed management strategy under various system conditions. Hardware-in-the-loop setup validates the implement-ability of the control strategy in dc microgrids. [ABSTRACT FROM AUTHOR]

Integrated-control solutions will play a significant role in future tokamaks, in which a variety of coupled control problems will need to be solved simultaneously by means of a limited number of actuators. In this article, the problem of simultaneously regulating the global toroidal rotation, $\Omega _\phi $ , and total plasma energy, $W$ , is tackled. These two 0-D variables, $\Omega _\phi $ and $W$ , depend on the ion toroidal rotation and electron temperature profiles, respectively. Both $\Omega _\phi $ and $W$ also depend on the electron density and safety factor profiles. The actuation methods considered in this article are co-current and counter-current neutral beam injection. A nonlinear, robust controller that makes use of Lyapunov redesign techniques is synthesized based on 0-D, control-oriented models of the $\Omega _\phi $ and $W$ dynamics. In addition, an actuator management scheme is designed to handle variations in the control priorities and availability of the neutral beam injectors. The actuator manager solves an optimization problem in real time in order to find the most appropriate course of action when unexpected changes occur. The integrated control architecture is tested for a DIII-D scenario by means of the 1-D code Control-Oriented Transport Simulator (COTSIM), which predicts the time evolution of the electron temperature, electron density, ion toroidal rotation, and safety factor profiles. [ABSTRACT FROM AUTHOR]

This paper presents an integrated control strategy to achieve fast start-up and enable wide input frequency operation in a three-phase six-switch power factor correction (PFC) converter. Limiting the inrush current with simultaneously minimizing the start-up time is achieved by implementing a nonlinear compensator in the voltage control loop. In addition, the concerning issues regarding unity PFC operation with an accurate reference tracking in a system with wide input frequency variation (typical for more-electric-aircraft) are resolved by a second-order compensator integrated with a state-feedback controller in the current loop. For a proof-of-concept verification, a hardware prototype of 6 kW, three-phase six-switch PFC is developed and tested with the proposed integrated control strategy in a wide source frequency range (360–800 Hz) ac input that shows perfect unity power factor operation throughout. Both the start-up time and inrush current are reduced to < \text50\% of their values in conventional PI compensation. [ABSTRACT FROM AUTHOR]

This paper proposes an advanced position-tracking control approach, referred to as an integrated intelligent nonlinear controller, for a pneumatic artificial muscle (PAM) system. Due to the existence of uncertain, unknown, and nonlinear terms in the system dynamics, it is difficult to derive an exact mathematical model with robust control performance. To overcome this problem, the main contributions of this paper are as follows. To actively represent the behavior of the PAM system using a grey-box model, neural networks are employed as equivalent internal dynamics of the system model and optimized online by a Lyapunov-based method. To realize the control objective by effectively compensating for the estimation error, an advanced robust controller is developed from the integration of the designed networks, and improvement of the sliding mode and backstepping techniques. The convergences of both the developed model and the closed-loop control system are guaranteed by Lyapunov functions. As a result, the overall control approach is capable of ensuring the system's performance with fast response, high accuracy, and robustness. Real-time experiments are carried out in a PAM system under different conditions to validate the effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

A generalized integrated control strategy for vehicle dynamics using an optimal torque vectoring control approach is extended in this paper. The central objective of this approach is to generate optimal additional tire forces and yaw moment over the vehicle through the application of individual wheel torque to keep the vehicle on a target path. This is achieved by minimizing the error between the actual and target forces and moment at the center of gravity (CG). In this paper, this methodology is extended to a constrained optimal control approach that handles additional real-time constraints, which has several vehicle control applications. An online optimization strategy is used to solve the resulting constrained optimization problem that gives the necessary tire force adjustments at the tire level. Some typical applications are 1) differential braking on all wheels, which is applicable to both electric and conventional cars and 2) hybrid torque vectoring on the front wheels and differential braking on the rear wheels. Both simulations and experimental results show the usefulness of this approach of handling constraints with this optimal torque vectoring control. [ABSTRACT FROM PUBLISHER]

In an urban rail transit system, issues regarding headway regulation have aroused wide attention. The assurance of headway regularity can decrease train delay times and average passenger waiting times. An integrated control method is proposed to optimize train headway by adjusting the train arrival time at stations. The adjustment of train arrival time is achieved by using an analytical method, and then the speed profile for each train is calculated by a suboptimal method, which has been applied in a practical system. Through simulation, the CPU time for calculating optimal train arrival time and speed profile is analyzed, respectively. The analysis demonstrates that the proposed method satisfies the real-time requirements for solving the headway regulation problem. By adopting the proposed method, the average passenger waiting time and the energy consumption can be decreased. In particular, the proposed method has better performance when the dispatch headway is large. [ABSTRACT FROM PUBLISHER]

This paper introduces the development and implementation of a ball mill grinding circuit simulator, NEUSimMill. Compared to the existing simulators in this field which focus on process flowsheeting, NEUSimMill is designed to be used for the test and verification of grinding process control system including advanced control system such as integrated control. The simulator implements the dynamic ball mill grinding model which formulates the dynamic responses of the process variables and the product particle size distribution to disturbances and control behaviors as well. First principles models have been used in conjunction with heuristic inference tools such as fuzzy logic and artificial neural networks: giving rise to a hybrid intelligent model which is valid across a large operating range. The model building in the simulator adopts a novel modular-based approach which is made possible by the dynamic sequential solving approach. The simulator can be initiated with connection to a real controller to track the plant state and display in real-time the effect of various changes on the simulated plant. The simulation model and its implementation is verified and validated through a case of application to the design, development, and deployment of optimal setting control system. [ABSTRACT FROM AUTHOR]

Buildings account for nearly 40% of global energy consumption. About 40% and 15% of that are consumed, respectively, by HVAC and lighting. These energy uses can be reduced by integrated control of active and passive sources of heating, cooling, lighting, shading and ventilation. However, rigorous studies of such control strategies are lacking since computationally tractable models are not available. In this paper, a novel formulation capturing key interactions of the above building functions is established to minimize the total daily energy cost. To obtain effective integrated strategies in a timely manner, a methodology that combines stochastic dynamic programming (DP) and the rollout technique is developed within the price-based coordination framework. For easy implementation, DP-derived heuristic rules are developed to coordinate shading blinds and natural ventilation, with simplified optimization strategies for HVAC and lighting systems. Numerical simulation results show that these strategies are scalable, and can effectively reduce energy costs and improve human comfort. [ABSTRACT FROM AUTHOR]

In this paper, the operation principle of a multiple converter, which is composed of the traditional two-level six-switch voltage source converter and constructed in line-voltage cascaded mode, is analyzed. The equivalent switching circuit model of the multiple converter is built based on its operation characteristic. By analyzing the feature of the multiple converter control, an improved voltage–current double-loop control strategy based on the proportional–resonant (PR) controller is proposed. The control strategy, which has the merit of the integrated control, can also realize the independent control of the transmission power of each unit of the multiple converter by adding the voltage-sharing compensation control. Meanwhile, a PR controller is adopted in the current loop. By giving a suitable current reference value for the controller, the problem of ac-side line-current asymmetry can be solved, and the effect of unbalanced grid voltages on the system can be avoided as well. The availability of the proposed control strategy is verified by the experimental results. [ABSTRACT FROM PUBLISHER]

In this paper, an integrated vehicle seat and suspension control strategy for a quarter car with driver model is proposed to improve suspension performance on driver ride comfort. An integrated seat and suspension model that includes a quarter-car suspension, a seat suspension, and a 4-degree-of-freedom (DOF) driver body model is presented first. This integrated model provides a platform to evaluate ride comfort performance in terms of driver head acceleration responses under typical road disturbances and to develop an integrated control of seat and car suspensions. Based on the integrated model, an H\infty state feedback controller is designed to minimize the driver head acceleration under road disturbances. Considering that state variables for a driver body model are not measurement available in practice, a static output feedback controller, which only uses measurable state variables, is designed. Further discussion on robust multiobjective controller design, which considers driver body parameter uncertainties, suspension stroke limitation, and road-holding properties, is also provided. Last, numerical simulations are conducted to evaluate the effectiveness of the proposed control strategy. The results show that the integrated seat and suspension control can effectively improve suspension ride comfort performance compared with the passive seat suspension, active seat suspension control, and active car suspension control. [ABSTRACT FROM PUBLISHER]

The rapid development of microelectromechanical systems (MEMS) technologies in recent years has provided a high degree of spatial miniaturization and integration of electromechanical components, which enable integrated sensing and control in manufacturing. This article provides an overview of the state of the art of micromachined microsensors for the measurement of mechanical signals in the manufacturing industry for automobiles, manufacturing, medical equipment, environment, robotics, food, and other consumer products. Measurements of pressure, acceleration, and acoustic emission (AE) are the three physical quantities that are most encountered in industrial and manufacturing applications. Discussed are the major design parameters of such microsensors, such as dynamic range, sensitivity, resolution, and accuracy and provide a real-world application. Also discussed are the issues related to the spatial integration of signal processing, power supply, and wireless communication with the sensing elements, which are of direct relevance to the overall performance of the microsensors. [ABSTRACT FROM PUBLISHER]