Research On Helicopter Vortex Ring Warning Method Based On Neural Network

When the helicopter is in vertical descent or steep descent,if it is not properly controlled,it is likely to fall into a vortex ring state that seriously endangers the flight safety of the helicopter.If it can give an early warning when the helicopter enters the vortex ring and prompt a reasonable way to change,the occurrence of such accidents can be effectively avoided.This paper aims at the helicopter vortex-ring state warning method research,and the main research content includes:(1)Through the contrast analysis of the current vortex state of the current helicopter,it is determined that the ideal vortex boundary calculating method,based on the difference of the helicopter into the vortex region,is divided by the different borders,and the different state of the helicopter,the different state of the loop,and the corresponding measures are made(2)Aiming at the accurate acquisition of low airspeed,one of the key problems of vortex ring warning,a prediction model of helicopter low airspeed based on BP neural network is established.In the end,based on the Matlab simulation,and using the four-rotor drone platform for the flight test,it is fully validated that the BP neural network algorithm is used to predict the validity and accuracy of low speed(3)Based on Simulink/Stateflow,BP neural network low airspeed prediction model and vortex ring warning mode logic model were established.At first,a BP neural network low airspeed prediction model was established based on Simulink,and a vortex ring warning logic model was established based on Stateflow.Finally,the two models were integrated,and the correctness of the model was verified through simulation and test(4)A semi-physical simulation experiment based on DSP was carried out.Based on DSP controller,the low airspeed prediction algorithm of BP neural network and the logic algorithm of vortex ring warning mode are realized by using C language,and the corresponding upper computer software is developed,and the corresponding semi-physical simulation hardware system is constructed.The correctness and effectiveness of the vortex ring warning method proposed in this paper are verified by experiments.