Fault self-repair strategy based on evolvable hardware and reparation balance technology

In the face of harsh natural environment applications such as earth-orbiting and deep space satellites, underwater sea vehicles, strong electromagnetic interference and temperature stress,the circuits faults appear easily. Circuit faults will inevitably lead to serious losses of availability or impeded mission success without self-repair over the mission duration. Traditional fault-repair methods based on redundant fault-tolerant technique are straightforward to implement, yet their area, power and weight cost can be excessive. Moreover they utilize all plug-in or component level circuits to realize redundant backup, such that their applicability is limited. Hence, a novel selfrepair technology based on evolvable hardware（EHW） and reparation balance technology（RBT） is proposed. Its cost is low, and fault self-repair of various circuits and devices can be realized through dynamic configuration. Making full use of the fault signals, correcting circuit can be found through EHW technique to realize the balance and compensation of the fault output-signals. In this paper, the self-repair model was analyzed which based on EHW and RBT technique, the specific self-repair strategy was studied, the corresponding self-repair circuit fault system was designed, and the typical faults were simulated and analyzed which combined with the actual electronic devices. Simulation results demonstrated that the proposed fault self-repair strategy was feasible. Compared to traditional techniques, fault self-repair based on EHW consumes fewer hardware resources, and the scope of fault self-repair was expanded significantly.     

压电致动器扑翼结构动力学仿真

采用传统扑动机构的微型扑翼,气动效率低、扑动能耗大。采用压电致动器的微型扑翼通过压电材料进行致动使机翼产生上下扑动,有效地将扑动机构和机翼两个主要系统进行集成,不仅节省重量,同时它具有任务变形自适应能力强、气动效率高和扑动能耗小的特点。通过PCL语言建立采用压电致动器的扑翼有限元模型,结合同尺寸扑翼气动力试验数据,进行采用压电致动器扑翼结构仿真。利用仿真结果研制采用压电致动器扑翼原理样机,研究表明,采用压电致动器后扑翼扑动频率得到明显提高,压电片可有效控制机翼的弯扭变形,有助于提高扑翼的气动效率。     

基于Semi-Markov模型的多态系统不完全维修决策

为提高复杂多态系统的任务完成能力,降低维修资源消耗,提出了基于Semi-Markov模型的预防性维修和修复性维修相结合的多态系统不完全维修决策方法。采用Semi-Markov模型描述部件的性能衰退过程,利用通用生成函数方法对系统的可靠性指标进行分析,在不完全维修模型基础上,从"系统级维修的角度"出发,提出了预防性维修和修复性维修相结合的不完全维修决策方法,确保系统在有限的服役期内,获得最大净效益。并以某航空发动机压气机子系统的维修决策为例进行分析,该方法可以有效的结合预防性维修和修复性维修的优势,提高了系统的任务完成能力,具有很强的通用性和工程应用价值。     

复合材料用混纤纱的结构与浸渍性能研究

利用达西定律分析了混纤纱结构对其体浸渍性能的影响，并分析了增强纤维／热塑性纤维并列纱，理想混纤纱，一般混纤纱的基体浸渍特征，增强纤的膨松以及增强纤维／热塑性纤维的良好混合度有利于基体的浸渍，复合材料的弯曲性能提高。     

C/E复合材料网格缠绕结构三维建模与模具设计

通过对圆柱螺旋线和圆锥螺旋线参数方程的推导,实现了网格结构及模具的三维建模。三维模型的建立,可实现结构空间协调,缩短设计周期,节省研制经费,提高生产效率。在此基础上提出了可行的金属模具设计方案,找到了切实可行的模具加工方法,并在工程中加以应用,取得了较好效果。     

View-dependent progressive transmission and rendering for lunar model based on bicubic subdivision-surface wavelet

Given the fact that the back of the digital lunar model is invisible from any viewpoint, a view-dependent progressive transmission and rendering method for lunar model is proposed and a client-server browsing system is implemented. On the server side, the semi-regular lunar surface is partitioned into dozens of segments, and each segment is compressed independently using bicubic subdivision-surface wavelet and SPIHT. For any viewpoint, only the data of the visible segments are transmitted to the client side progressively, then decoded and locally reconstructed there. This approach not only improves the efficiency of transmission, but also reduces the reconstruction time greatly. We can browse the lunar model on the client almost in realtime.     

近程反导舰炮拦截掠海目标供靶需求分析

针对舰炮武器系统设计定性试验供靶飞行速度低、飞行高度降不下来,且小航路捷径供靶实现难度大风险高,因此考核标准低,难以对舰炮武器系统进行有效充分考核等问题,从舰炮武器系统试验靶标供靶的速度、高度、航路捷径等方面分析了影响目标毁伤概率的因素,建立了毁伤概率计算模型。通过实际验算论证了近程反导舰炮拦截掠海导弹类目标时,如果目标速度低、飞行高度高、航路捷径大,对此类目标的毁伤概率将明显增大,导致武器系统考核标准降低。提出了为真实考核武器装备的作战效能,要采用速度高、掠海飞行、航路捷径小的靶弹类目标进行拦截试验,以解决试验的充分性、边界条件问题,实现从严考核之目的。     

航空拖曳诱饵系统的动态特性研究简

 为准确预测航空拖曳诱饵系统能否干扰成功,建立了系统的物理数学模型并对其动态特性进行了仿真研究。应用集中质量法,将柔性拖曳缆绳离散为一系列由阻尼弹簧连接的节点,建立了缆绳的动态模型;对诱饵进行受力分析,建立了诱饵的六自由度模型;提出了缆绳与诱饵的耦合条件,使模型更加精确。分别对诱饵释放过程中,以及释放完成后载机机动时系统的动态特性进行了仿真研究,给出并分析了缆绳的形状、张力和诱饵的姿态角等参数的变化规律。结果表明：为避免出现“鱼钩”现象,应尽可能减小释放诱饵的初速度与载机空速的夹角;应按梯形速度释放诱饵,以使缆绳中拉力的最大值较小。释放完成后,应控制载机最大飞行速度,以避免缆绳进入载机的高温尾喷流区;载机作盘旋时,缆绳在载机的圆形轨迹之外,且载机飞行速率一定时,角速度越大,缆绳向外趋势越大,越有利于避开载机的尾喷流区。     

航空拖曳诱饵系统的动态特性研究

为准确预测航空拖曳诱饵系统能否干扰成功,建立了系统的物理数学模型并对其动态特性进行了仿真研究。应用集中质量法,将柔性拖曳缆绳离散为一系列由阻尼弹簧连接的节点,建立了缆绳的动态模型;对诱饵进行受力分析,建立了诱饵的六自由度模型;提出了缆绳与诱饵的耦合条件,使模型更加精确。分别对诱饵释放过程中,以及释放完成后载机机动时系统的动态特性进行了仿真研究,给出并分析了缆绳的形状、张力和诱饵的姿态角等参数的变化规律。结果表明：为避免出现“鱼钩”现象,应尽可能减小释放诱饵的初速度与载机空速的夹角;应按梯形速度释放诱饵,以使缆绳中拉力的最大值较小。释放完成后,应控制载机最大飞行速度,以避免缆绳进入载机的高温尾喷流区;载机作盘旋时,缆绳在载机的圆形轨迹之外,且载机飞行速率一定时,角速度越大,缆绳向外趋势越大,越有利于避开载机的尾喷流区。