不确定控制系统的设计

AbstractABSTRACTMost of the helicopters in use is lifted by one rotor,and on most of which,thetorque generated by the rotor is counterbalanced by tail rotor,which becomesincreasingly sophisticated after years of development.However,with the limitationfrom its prototype structure,the disadvantages are becoming increasingly oppressive.So the idea that the antitorque could be squeezed out from the main rotor wake by thecirculation control tail boom was provided by the Hughes Corporation,the authoralso conceived a tail boom with backward extending wing for the same use.A cantoin this paper will check these concepts for future uses.Helicopters have poorerstability than the fixed-wing airplanes,practical helicopters are equipped withautopilots or stabilizers without exception to relieve the heavy burdens on the pilotsand to gain sufficient stability and suitable maneuverability.The rest of the paper willdevote to an attempt of stabilizer design for one flight condition.The feasibility of antitorque using power in downwash will be examined by thecalculation,which was executed by a combined algorithm of momentum and bladesection,of the lifting and torque of the hovering main rotor.After improvementsderived from understanding of eigenvalue perturbation theory and the trait ofcontrolling problem,new robust pole design algorithm maintains its advantages overRobust Control theory by easy to use.The designing method of both static anddynamic state feedback controller are given,with the tools will be used.The calculation of the hovering main rotor indicates that the counter balancetorque provided by the power from main rotor wake is only a little proportion to thatof needed,which sentences the assumption impractical.New robust pole designalgorithm got some harvests,with the discussion using some criteria of the root locustheory,blindness in poles assigning are partly avoided.After the discussion about theinfluence of dynamics of actuators,the new algorithm executes the dynamic stabilizerdesign.Despite its persuasion on theory,the dynamic controller design methodexhibits poorly,partly due to the limitations from the underlying optimum algorithms.So the strives towards offering counter balance torque with special designed tailboom on single rotor helicopters may be acarpous now.Using the improved designalgorithm,better controllers can be acquired sometimes.Key Words:calculations of hovering rotor;Robust Pole Assignment;robust poledesign;root locus;dynamic of actuator;stabilizer design