A bridgeless buck-boost power-factor-correction (PFC) rectifier with positive output voltage is proposed herein. This PFC rectifier operates in the discontinuous conduction mode (DCM). Owing to the DCM, a good performance on PF is easily achieved as well as no reverse recovery currents being generated from the diodes. By means of output voltage sensing along with the traditional voltage-follower control, a proper control force is created to drive the switches. By doing so, not only the output voltage is stably controlled at a given value, but also the input current tracks the input voltage as tightly as possible. In addition, the accompanying harmonic distortion meets the requirements of the IEC6100-3-2 Class C harmonics standard, and accordingly, the proposed rectifier is suitable for the AC-DC LED driver. Finally, via mathematical deductions and experimental results, the effectiveness of the proposed bridgeless buck-boost PFC rectifier is verified.

In this paper, the attitude control of aircraft with multiple inertial measurement units under the influence of unknown gyro zero drift and external disturbance is studied. First of all, the observers are designed to estimate the zero drift biases based on the consensus algorithm. The angular velocity used for aircraft control is obtained by compensating the biases. Then, considering the external disturbance in the aircraft motion, this paper introduces a super-twisting sliding-mode algorithm to design the observer in order to compensate the disturbance. In addition, based on the proposed observers, a controller is designed to realize attitude control of the aircraft with the gyro zero drift and the external disturbance. Finally, the simulation results are given to verify the effectiveness of the proposed control law.

This article mainly considers the problem of trajectory tracking control problem of quad-rotor system with velocity constrain under the consideration of safety. A model-based nonlinear controller is proposed which can guarantee not only the asymptotical stability for control system but also the velocity under a safe range. Firstly, based on backstepping design, a position tracking controller with velocity constraint is proposed to ensure that the desired position can be tracked with velocity constrains. At the second step, considering attitude subsystem, an attitude controller is proposed to improve the attitude dynamic response performance. Finally, the validity and superiority of the design has been verified in simulation results.

To improve the path-tracking ability and road adaptability for articulated vehicle with a trailer, this paper proposes an advanced path-tracking strategy, which is designed using the model predictive control method and an optimal curvature preview control technique. Firstly, a linear vehicle model was generated and its fidelity was verified. Then the model predictive controller was designed and used to reduce the lateral tracking error in curved path negotiations, and the optimal curvature preview control strategy was designed to improve the driving stability in straight road operation. Finally, a co-simulation platform based on Trucksim and Simulink software was built, and cosimulations were carried out under the double lane change and the single lane change maneuvers at different vehicle speeds. Simulation results show that the proposed path-tracking controller exhibits better performance than the optimal preview controller. The path-tracking ability and the driving stability are also excellent in the whole driving process for the single-trailer articulated vehicle.

This paper presents a design synthesis approach for the development of autonomous steering control schemes for articulated vehicles. To design the autonomous steering controller, a 3 degrees of freedom (DOF) yaw-plane model is generated to represent a car-trailer combination, and a model predictive control (MPC) algorithm is used for lateral position and yaw motion control of the articulated vehicle. For enhancing the performance of the self-steering articulated vehicle, the design synthesis of the autonomous driving control schemes is formulated as a design optimization problem. Two optimization algorithms, namely Particle Swarm Optimization (PSO) and Differential Evolution (DE), are introduced and tested for the design optimization. In the design synthesis, the design variables may include passive vehicle design variables, e.g., geometric. To demonstrate the effectiveness of the proposed design synthesis approach, selected simulation results are presented and analyzed. The insightful findings attained from the study may be used as guidelines for developing autonomous driving control systems of articulated vehicles.