A comprehensive method based on system identification theory for helicopter flight dynamics modeling with rotor degrees of freedom is developed. A fully parameterized rotor flapping equation for identification purpose...A comprehensive method based on system identification theory for helicopter flight dynamics modeling with rotor degrees of freedom is developed. A fully parameterized rotor flapping equation for identification purpose is derived without using any theoretical model, so the confidence of the identified model is increased, and then the 6 degrees of freedom rigid body model is extended to 9 degrees of freedom high-order model. Bode sensitivity function is derived to increase the accuracy of frequency spectra calculation which influences the accuracy of model parameter identification. Then a frequency domain identification algorithm is established. Acceleration technique is developed furthermore to increase calculation efficiency, and the total identification time is reduced by more than 50% using this technique. A comprehensive two-step method is established for helicopter high-order flight dynamics model identification which increases the numerical stability of model identification compared with single step algorithm. Application of the developed method to identify the flight dynamics model of BO 105 helicopter based on flight test data is implemented. A comparative study between the high-order model and rigid body model is performed at last. The results show that the developed method can be used for helicopter high-order flight dynamics model identification with high accuracy as well as efficiency, and the advantage of identified high-order model is very obvious compared with low-order model.展开更多
Polarization-based integrated navigation system(PINS)that combines the polarization sensor(PS)and the inertial navigation system(INS)has been widely recognized as an effective solution for acquiring attitude informati...Polarization-based integrated navigation system(PINS)that combines the polarization sensor(PS)and the inertial navigation system(INS)has been widely recognized as an effective solution for acquiring attitude information of unmanned aerial vehicles(UAVs).However,based on the PINS hardware configuration,the accurate acquisition of UAV position information remains a challenge.In this article,we propose an improved PS/INS integrated navigation scheme by incorporating an embedded UAV dynamic model(UDM).Compared with existing PS/INS fusion methods,the presented PINS enables the optimal estimation of the UDM thrust coefficient error along with other system state elements,thus significantly improving the UDM accuracy.On this basis,the UDM and PS are used to fuse with the INS,which improves the estimation accuracy of both the UAV attitude and position.Furthermore,we employ an adaptive fusion strategy to detect the reliability of PS data.Therefore,once the UDM is corrected using reliable PS data,it can further fuse with the INS,thereby improving the environmental adaptability of the PINS.The simulation and flight experiment results verified the effectiveness of the proposed PS/INS/UDM integrated navigation scheme.展开更多
基金the support of the Fund of Key Laboratory of Chinaa Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions of China
文摘A comprehensive method based on system identification theory for helicopter flight dynamics modeling with rotor degrees of freedom is developed. A fully parameterized rotor flapping equation for identification purpose is derived without using any theoretical model, so the confidence of the identified model is increased, and then the 6 degrees of freedom rigid body model is extended to 9 degrees of freedom high-order model. Bode sensitivity function is derived to increase the accuracy of frequency spectra calculation which influences the accuracy of model parameter identification. Then a frequency domain identification algorithm is established. Acceleration technique is developed furthermore to increase calculation efficiency, and the total identification time is reduced by more than 50% using this technique. A comprehensive two-step method is established for helicopter high-order flight dynamics model identification which increases the numerical stability of model identification compared with single step algorithm. Application of the developed method to identify the flight dynamics model of BO 105 helicopter based on flight test data is implemented. A comparative study between the high-order model and rigid body model is performed at last. The results show that the developed method can be used for helicopter high-order flight dynamics model identification with high accuracy as well as efficiency, and the advantage of identified high-order model is very obvious compared with low-order model.
基金supported by the National Natural Science Foundation of China(Grant Nos.62388101,62425302,62227813,62373033,62403024)the National Key R&D Program of China(Grant No.2020YFA0711200)。
文摘Polarization-based integrated navigation system(PINS)that combines the polarization sensor(PS)and the inertial navigation system(INS)has been widely recognized as an effective solution for acquiring attitude information of unmanned aerial vehicles(UAVs).However,based on the PINS hardware configuration,the accurate acquisition of UAV position information remains a challenge.In this article,we propose an improved PS/INS integrated navigation scheme by incorporating an embedded UAV dynamic model(UDM).Compared with existing PS/INS fusion methods,the presented PINS enables the optimal estimation of the UDM thrust coefficient error along with other system state elements,thus significantly improving the UDM accuracy.On this basis,the UDM and PS are used to fuse with the INS,which improves the estimation accuracy of both the UAV attitude and position.Furthermore,we employ an adaptive fusion strategy to detect the reliability of PS data.Therefore,once the UDM is corrected using reliable PS data,it can further fuse with the INS,thereby improving the environmental adaptability of the PINS.The simulation and flight experiment results verified the effectiveness of the proposed PS/INS/UDM integrated navigation scheme.
