Research On Reconfigurable Control System Design Of Heavy Launch Vehicle

To improve the ability of entering the space, expand the space for developmentof aerospace industry and boost the level of aerospace technology, significantstrategic meaning lies in the development of new generation heavy launch vehicle.In the powered phase of new generation of heavy launch vehicle, attitude control isexecuted by the joint swing of both core and booster engines. Increased number ofactuators enhanced the capability of control system, but also increased itscomplexity and the odds of failure. This paper studied the control technique of coreand booster engines’ joint swing, the reconfigurable control of heavy launch vehiclefor higher reliability. The specific contents include:The current development situation of heavy launch vehicle of differentcountries is surveyed in detail. The problems in the design of new generation ofheavy launch vehicle are discussed. The development and its trend ofreconfigurable control are analyzed.The dynamical model of heavy launch vehicle in first-stage phase flight isestablished. Then different kinds of actuators failure are analyzed and thecorresponding mathematical modeling is completed.Considering the redundant control of multiple actuators and the advantage ofredundant control system design using allocation, the approach to design the controlsystem of heavy launch vehicle based on allocation and the algorithm of allocationare studied. A hybrid allocation control strategy, based on pseudo-inverse andfixed-point method, with minor calculation and consideration of the restraints ofactuators is proposed.According to the nonlinearity, coupling and other characteristics of heavylaunch vehicle, based on singular perturbation theory and principle of time-scaleseparation, controller divided into fast and slow loops is design based on nonlineardynamical inversion. The results of simulation proved the good performance ofnonlinear dynamical decoupling control law.In the end, the structure of reconfigurable control system based on allocation isproposed. The strategies of allocation under different fault scenarios are proposed.Results of6DOF simulation show that reconfigurable control system based on allocation can comparatively solve the allocation of redundant control of multipleactuators, effectively improve the safety and reliability of heavy launch vehiclewhen faults occur. The pseudo-inverse method and the hybrid allocation controlstrategy have quite well real time performance.