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Zhang J.,Beijing Institute of Mechanical Equipment | Zhang J.,Harbin Institute of Technology | Ma K.,Harbin Institute of Technology | Meng G.,Harbin University of Science and Technology | Tian S.,Harbin Institute of Technology
IEEE Transactions on Aerospace and Electronic Systems | Year: 2015

Attitude control is investigated for a rigid spacecraft using single gimbal control moment gyros (SGCMGs) as actuators. By taking spacecraft and SGCMGs as an integrated system, the combined dynamics of SGCMGs and spacecraft are fully considered. The singularity problem of the SGCMGs is converted into the problem of state constraints and input constraints, and by so doing, the actuation capacity of the SGCMGs is fully utilized. To ensure accurate real-time computation, the Gauss pseudospectral and sequential quadratic programming methods are used to solve the attitude path planning of the system. Considering the uncertainties of the external disturbances and the estimation error of the inertia matrix, feedback control of the system is designed by using nonlinear model predictive control. Finally, dual-mode model predictive control is used to ensure the stability of the system, and the H∞ controller and the estimated hyperellipsoid region of attraction of the linearized system are given. Simulation results show good tracking performance and robustness of the designed controller. The modeling method and the control method given in the paper provide a solution to the singularity problem of the SGCMGs. © 2015 IEEE.

Wen Q.,Beijing Institute of Technology | Xia Q.,Beijing Institute of Technology | Weixia S.,Beijing Institute of Mechanical Equipment
Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering | Year: 2015

This note studies the problem of impact angle guidance by considering the seeker's field-of-view angle constraint and proposes a new guidance parameter design strategy based on the classical time-to-go weighted impact angle optimal guidance law. To this end, firstly, the analytic expression of the field-of-view angle throughout the guidance process is presented. It is demonstrated that the max field-of-view angle can be controlled by designing the correct time-to-go weighted parameter and initial guidance conditions. Then, a guidance strategy, which includes the optimal guidance law, guidance condition selection, and guidance parameter design, is given. When using the strategy, the suitable time-to-go weighted parameter is modified to ensure the seeker's field-of-view angle would not exceed the boundary value. Finally, the results of a numerical simulation based on the simple missile-target kinematics are presented; these results validate the proposed strategy. © IMechE 2015.

Qiuqiu W.,Beijing Institute of Technology | Qunli X.,Beijing Institute of Technology | Weixia S.,Beijing Institute of Mechanical Equipment
Journal of Aerospace Engineering | Year: 2016

To avoid the mathematical singularity of polar converting in bank-to-turn (BTT) guidance and to provide the specified terminal impact angle, a BTT guidance law with impact-angle constraint (BTT-GL/IA) is presented. Considering the influence of the impact-angle control and target maneuver to the miss-distance, a new form zero-effort miss-distance with impact angle (ZEM/IA) is introduced. Referring to the Lyapunov-like approach used to drive the guidance law in the prior literature, a Lyapunov function is constructed in terms of ZEM/IA. Based on the Lyapunov stability theorem, a negative definite function is designed, and the BTT-GL/IA is derived. Next, BTT-GL/IA is implemented in another form with the variables as the line-of-sight angle and its rate, which are easily measured by the seeker. When using BTT-GL/IA, the guidance law tends to maintain smooth and continuously-varied body acceleration and roll-angle commands while satisfying the impact position and angle constraints. The problem of a mathematical singularity in normal BTT polar converting logic is avoided. Finally, both the maneuverable and stationary targets with different impact-angle constraints are considered in numerical simulations. Through various simulation results, the effectiveness and practicality of the BTT-GL/IA are demonstrated. © 2015 American Society of Civil Engineers.

Zhong H.,Beijing Institute of Mechanical Equipment | Zhao W.,Second Research Institute China Arerospace Science and Industry Corporation office | Sun Y.,Second Research Institute China Arerospace Science and Industry Corporation office
Applied Mechanics and Materials | Year: 2014

The slip-judgment method of threshold value was made for all-wheel independent electric drive vehicle through the analysis of the relationship of steering kinematics, which based on detecting speed and current of wheel-motor. The speed coordinated control of motor was used as synchronous control method. Models of vehicle dynamics and synchronous control were respectively constructed in Adams and Matlab/Simulink, which composed the model of mechanical-electric collaborative simulation. The synchronous control process of vehicle that running on bisectional road was analyzed, the result shows that synchronous control based on power control strategy reduces slip-wheel motor's power consumption and increases other motors' output power and torque through reducing the motor speed to average speed of normal wheel-motor. Improves the traction performance and stability of vehicle, also reduces the wheel wear and driver's control difficulty. The method has advantages of low cost, wide applicability, good controllability, high reliability etc., provide the reference of synchronization technology for independent electric drive military vehicle. © (2014) Trans Tech Publications, Switzerland.

Chen C.,Beijing Institute of Technology | Chen C.,North China Electrical Power University | Wang Y.,Beijing Institute of Mechanical Equipment | Tian Z.,Beijing Institute of Mechanical Equipment
Chinese Control Conference, CCC | Year: 2015

Launch equipment hydraulic system plays a vital role in completion of mission due to its stability and accuracy. This paper built an effectiveness evaluation index system based on comprehensive analysis of launch equipment hydraulic system, compared weighting factor determination mechanisms, and integrated independence factor into weight determination by combining the strong coupling feature of launch equipment hydraulic system indexes. The final weight was integrated and determined in four aspects, including importance weight, information weight, independence weight and credibility weight. Then, the paper obtained the system effectiveness evaluation results by utilizing system operation data, and provided theoretical and data reference for equipment selection and effectiveness improvement. © 2015 Technical Committee on Control Theory, Chinese Association of Automation.

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