A new approach to gain-scheduling of H∞controllers is proposed for a cruise missile with variableswept wings( VSW) in bank-to-turn( BTT) mode. A nonlinear dynamic model is established and anticipant performance crite...A new approach to gain-scheduling of H∞controllers is proposed for a cruise missile with variableswept wings( VSW) in bank-to-turn( BTT) mode. A nonlinear dynamic model is established and anticipant performance criterions are given at first. For the selected operating points,feedback robust controllers of threechannels are designed independently to restrain cross-channel couple disturbances and aerodynamic perturbations. Then,the sweepback and Ma number are selected to schedule controller gains iteratively to ensure all closed-loop poles locating inside the desired region. The proposed method here attempts to extend the performance of initial design obtained for a single arbitrary point to the whole linearized domain while maintaining the expected stability over the entire range of sweepback and full flight envelope. Some time-domain analysis procedures based on the proposed method are carried out and assessed,while the performance of tracking and robustness to aerodynamic perturbations in different situations are contrasted by some nonlinear simulations. Finally,the numerical simulations demonstrate that the proposed autopilot design method has better tracking performance and is robust,effective and feasible.展开更多
随着对于大规模人群聚集活动的监控需求日益凸显,基于Wi-Fi的人群密度监测技术逐渐应用于公共安全管理,但其受限于RSSI(received signal strength indicator)的显著波动性与MAC地址匿名化造成的个体识别困难,特别在高密度场景下,其估计...随着对于大规模人群聚集活动的监控需求日益凸显,基于Wi-Fi的人群密度监测技术逐渐应用于公共安全管理,但其受限于RSSI(received signal strength indicator)的显著波动性与MAC地址匿名化造成的个体识别困难,特别在高密度场景下,其估计精度与稳定性仍难以保障。对此,提出一种抗随机性的Wi-Fi探针数据人群密度估计方法,通过设计一种基于时间窗的累计RSSI计算策略,利用局部建模构建区域密度映射关系,捕捉区域人群的动态变化,实现了复杂环境下稳定人群密度估计。所提方法在米级精度上分别取得了0.9723的整体准确率和0.8974的高密度场景准确率,实验结果表明其性能良好,具备跨场景推广的理论潜力与良好的泛用性。展开更多
基金Sponsored by Armament Department Pre-Research Foundation of China(Grant No.9140A31010114JB25465)Natural Science Foundation of Jiangsu Province(Grant No.BK20140795)Chinese Aerospace CAST Innovation Foundation(Grant No.CAST2014-27)
文摘A new approach to gain-scheduling of H∞controllers is proposed for a cruise missile with variableswept wings( VSW) in bank-to-turn( BTT) mode. A nonlinear dynamic model is established and anticipant performance criterions are given at first. For the selected operating points,feedback robust controllers of threechannels are designed independently to restrain cross-channel couple disturbances and aerodynamic perturbations. Then,the sweepback and Ma number are selected to schedule controller gains iteratively to ensure all closed-loop poles locating inside the desired region. The proposed method here attempts to extend the performance of initial design obtained for a single arbitrary point to the whole linearized domain while maintaining the expected stability over the entire range of sweepback and full flight envelope. Some time-domain analysis procedures based on the proposed method are carried out and assessed,while the performance of tracking and robustness to aerodynamic perturbations in different situations are contrasted by some nonlinear simulations. Finally,the numerical simulations demonstrate that the proposed autopilot design method has better tracking performance and is robust,effective and feasible.
文摘随着对于大规模人群聚集活动的监控需求日益凸显,基于Wi-Fi的人群密度监测技术逐渐应用于公共安全管理,但其受限于RSSI(received signal strength indicator)的显著波动性与MAC地址匿名化造成的个体识别困难,特别在高密度场景下,其估计精度与稳定性仍难以保障。对此,提出一种抗随机性的Wi-Fi探针数据人群密度估计方法,通过设计一种基于时间窗的累计RSSI计算策略,利用局部建模构建区域密度映射关系,捕捉区域人群的动态变化,实现了复杂环境下稳定人群密度估计。所提方法在米级精度上分别取得了0.9723的整体准确率和0.8974的高密度场景准确率,实验结果表明其性能良好,具备跨场景推广的理论潜力与良好的泛用性。
