Research On Lateral Control Technology In Forward Flight Of Unmanned Helicopter

The unmanned helicopter forward flight mode is similar with fixed wing aircraft flying at high speed in the term of the aerodynamic characteristics,so control mode is also close,that the strategy control system dealing with side wind disturbance consists of sideslip way and crab way.The unmanned helicopter flight control research in China is only application of sideslip way in flight.In addition,the unmanned helicopter flight trim equilibrium nominal value is very easy to change,and the control system is difficult to follow,so there is a trim problem.The former shows that the system of unmanned helicopter forward flight response to side wind missing crab way,the latter shows that constant trim can not be measured for control system.In this dissertation,we give solutions to the two problems in the lateral forward flight.In response to side wind disturbance problem,this dissertation demonstrates irrationality and insecurity in the application of sideslip way in flight.Then take the heading stability as the starting point of two control strategies are given,one is the heading open loop anti slip control with compensation using heading stability,the other is anti slip control based on feedback mothed with strengthening heading stability.In the second strategy,the author first designs control law that sideslip angle is feedbacked directly to prove the feasibility of the method.And then according to the overload and the sideslip angle lateral equivalence principle,feedback it to the control system.Finally,we get two engineering oriented crab way realization.In trim problem,this dissertation starts from the track control,finding corresponding relation of lateral offset and the trim of lateral cyclic pitch in the steady state.Then according to the relationship between trim and increment control in the control system,to design automatic trim control in the way that feedforward match feedback.The control law can realize the function that component,lateral offset reflecting change of constant trim,transferred to trim systim.At the end of this dissertation,the author introduces the development process of the nonlinear helicopter model program,YASim.And the results will fill the vacancy of the embedded simulation system lack of high confidence level and configurable helicopter model in the laboratory.