针对直升机飞行动力学建模参数优化问题,提出了一种基于粒子群的线性变参数模型预测控制(Linear parameter variable and model predictive control,LPV-MPC)优化设计,通过优化建模参数,提高直升机飞行动力学建模精度。基于经过滤波加...针对直升机飞行动力学建模参数优化问题,提出了一种基于粒子群的线性变参数模型预测控制(Linear parameter variable and model predictive control,LPV-MPC)优化设计,通过优化建模参数,提高直升机飞行动力学建模精度。基于经过滤波加权的前飞速度和横向速度对操纵量、姿态角、气动导数和操纵导数进行三维插值,对气动力进行实时计算,完成了UH-60直升机的LPV-MPC系统建模。采用粒子群优化算法,针对前飞速度插值间隔、横向速度插值间隔和滤波常数等三个建模参数进行优化。利用UH-60直升机非线性模型生成一系列用于优化的线性状态空间模型,对直升机纵向通道、横向通道同时给定激励进行仿真试验。仿真结果表明:在一定范围内任意选取的优化参数,经过粒子群寻优后,建立的LPV-MPV模型精度更高。展开更多
A new geometric model of Multiaxial Warp-Knitted (MWK) performs, which is based on the experimental observations and analysis of basic stitch, is developed to relate the geometric parameters and process variables. The...A new geometric model of Multiaxial Warp-Knitted (MWK) performs, which is based on the experimental observations and analysis of basic stitch, is developed to relate the geometric parameters and process variables. The fiber volume fraction and fibre orientation of MWK reinforced composites are described in terms of structural and processing parameters in the model. And this model provides a basis for the prediction of mechanical behavior of the MWK reinforced composites.展开更多
The grey system theory and the artificial neural network technology were applied to predict the sewing technical condition. The representative parameters, such as needle, stitch, were selected. Prediction model was es...The grey system theory and the artificial neural network technology were applied to predict the sewing technical condition. The representative parameters, such as needle, stitch, were selected. Prediction model was established based on the different fabrics’ mechanical properties that measured by KES instrument. Grey relevant degree analysis was applied to choose the input parameters of the neural network. The result showed that prediction model has good precision. The average relative error was 4.08% for needle and 4.25% for stitch.展开更多
文摘针对直升机飞行动力学建模参数优化问题,提出了一种基于粒子群的线性变参数模型预测控制(Linear parameter variable and model predictive control,LPV-MPC)优化设计,通过优化建模参数,提高直升机飞行动力学建模精度。基于经过滤波加权的前飞速度和横向速度对操纵量、姿态角、气动导数和操纵导数进行三维插值,对气动力进行实时计算,完成了UH-60直升机的LPV-MPC系统建模。采用粒子群优化算法,针对前飞速度插值间隔、横向速度插值间隔和滤波常数等三个建模参数进行优化。利用UH-60直升机非线性模型生成一系列用于优化的线性状态空间模型,对直升机纵向通道、横向通道同时给定激励进行仿真试验。仿真结果表明:在一定范围内任意选取的优化参数,经过粒子群寻优后,建立的LPV-MPV模型精度更高。
文摘A new geometric model of Multiaxial Warp-Knitted (MWK) performs, which is based on the experimental observations and analysis of basic stitch, is developed to relate the geometric parameters and process variables. The fiber volume fraction and fibre orientation of MWK reinforced composites are described in terms of structural and processing parameters in the model. And this model provides a basis for the prediction of mechanical behavior of the MWK reinforced composites.
文摘The grey system theory and the artificial neural network technology were applied to predict the sewing technical condition. The representative parameters, such as needle, stitch, were selected. Prediction model was established based on the different fabrics’ mechanical properties that measured by KES instrument. Grey relevant degree analysis was applied to choose the input parameters of the neural network. The result showed that prediction model has good precision. The average relative error was 4.08% for needle and 4.25% for stitch.
