新机研制中的复合材料结构装配关键技术

复合材料的特点决定了其结构的装配连接难度大、技术要求高.与国外飞机制造公司相比,我国复合材料结构制造装配方面的基础差、技术水平低.     

无人机飞行控制系统先进设计技术评述

首先简要回顾了无人机飞行控制系统经典设计方法,然后着重论述了目前国外在无人机飞行控制系统设计领域的最新研究成果,包括动态逆技术、BACKSTEPPING自适应技术及综合制导与控制技术。     

无人自转旋翼机建模与控制方法研究

以500kg级无人自转旋翼机为研究对象,研究了样例无人旋翼机的建模和自动飞行控制技术.首先,基于解析形式叶素积分法给出自转旋翼机的建模方法,并给出了样例旋翼无人机的数学模型;然后,设计了无人旋翼机的俯仰和滚转控制律,并在此基础上设计了速度、高度及侧偏控制律.最后,通过飞行试验验证了模型的准确性及控制律的有效性.     

可靠性设计优化的球空间设计法

可靠性设计优化（RBDO）在航空航天等领域已经被广泛应用，具有显著提高可靠性的效果；然而它包含两个迭代循环-总体优化循环和可靠性分析循环，双循环求解方法效率低下甚至难以承受。本文提出一种可以提高可靠性设计优化求解效率的方法-球空间设计法，该方法可以方便地表达搜索区域，最大可能失效点可以从极值点处精确获取；同时，该方法可以将总体优化以及可靠性分析同步进行。本文所提出的球空间法的有效性将通过2个算例进行测试，测试结果表明该方法不仅精度与同类方法持平，求解效率有明显提升，它将会对提高航空航天装备如卫星、火箭、飞行器等产品的可靠性提供更为有效的方法和技术支持。     

Event-triggered attitude control of spacecraft

The problem of spacecraft attitude stabilization control system with limited communication and external disturbances is investigated based on an event-triggered control scheme. In the proposed scheme, information of attitude and control torque only need to be transmitted at some discrete triggered times when a defined measurement error exceeds a state-dependent threshold. The proposed control scheme not only guarantees that spacecraft attitude control errors converge toward a small invariant set containing the origin, but also ensures that there is no accumulation of triggering instants. The performance of the proposed control scheme is demonstrated through numerical simulation.     

Orbit determination and prediction of GEO satellite of BeiDou during repositioning maneuver

In order to establish a continuous GEO satellite orbit during repositioning maneuvers, a suitable maneuver force model has been established associated with an optimal orbit determination method and strategy. A continuous increasing acceleration is established by constructing a constant force that is equivalent to the pulse force, with the mass of the satellite decreasing throughout maneuver. This acceleration can be added to other accelerations, such as solar radiation, to obtain the continuous acceleration of the satellite. The orbit determination method and strategy are illuminated, with subsequent assessment of the orbit being determined and predicted accordingly. The orbit of the GEO satellite during repositioning maneuver can be determined and predicted by using C-Band pseudo-range observations of the BeiDou GEO satellite with COSPAR ID 2010-001A in 2011 and 2012. The results indicate that observations before maneuver do affect orbit determination and prediction, and should therefore be selected appropriately. A more precise orbit and prediction can be obtained compared to common short arc methods when observations starting 1 day prior the maneuver and 2 h after the maneuver are adopted in POD (Precise Orbit Determination). The achieved URE (User Range Error) under non-consideration of satellite clock errors is better than 2 m within the first 2 h after maneuver, and less than 3 m for further 2 h of orbit prediction.     

一种手持式太赫兹探测系统的光学及结构设计*

随着现代安检技术与健康、隐私问题之间的矛盾愈加突出,人们迫切需要高效、便捷、安全的安检技术。首先介绍太赫兹非成像光谱探测技术的原理,提出适合于安检应用的太赫兹光谱探测系统技术指标,然后基于ZEMAX设计出配合该技术指标的光学系统,采用非序列模式对其进行仿真和评价,最后基于ProE设计完成了配合上述光学系统的紧凑型探测系统结构,实现了探测系统的手持式应用。     

民用飞机副翼舱结构振动疲劳寿命预计

副翼舱是民用飞机重要部件之一,主要作用为连接副翼并对安装副翼提供支持,将副翼的气动载荷传递到主翼盒上。当受到气动力及其他激励时副翼舱结构产生结构振动响应。副翼舱结构振动疲劳寿命需满足民用飞机适航条款要求,为表明满足适航条款符合性,对随机动载荷激励下副翼舱结构进行振动疲劳寿命预计具有重要意义。以民用飞机副翼舱结构为研究对象,基于试飞实测应变数据、金属材料的随机振动S-N曲线和改进声疲劳寿命估算法,提出了一种适用于振动疲劳寿命预计的工程处理方法。通过飞行试验、有限元仿真、数据分析等相结合的方法进行副翼舱结构优化前后的振动疲劳寿命预计。副翼舱结构优化前损伤位置预测寿命最低为59飞行小时,符合实际损伤位置寿命情况。副翼舱结构优化后应力水平明显降低,寿命满足要求。结果表明：基于实测数据的副翼舱结构振动疲劳寿命预计方法有效,可作为振动疲劳寿命预计的工程处理方法。     

某Ⅰ级涡轮盘低循环疲劳寿命试验研究

为了确定某Ⅰ级涡轮盘的技术寿命,根据该盘的标准循环载荷谱,对该盘进行了应力分析,确定在标准循环时该盘中心孔与径向销孔相交处为考核部位。为模拟标准循环时该盘在其考核部位的应力谱,专门设计了该Ⅰ级涡轮盘的试验转子及试验参数,在轮盘低循环疲劳试验器上,对该Ⅰ级涡轮盘的一个旧盘进行了高温低循环疲劳试验。试验结果表明：该旧盘低循环疲劳试验至第６０４７ 次循环时,有５ 个销孔考核部位出现了裂纹。断口分析表明：该旧盘剩余的试验低循环疲劳失效寿命为６０４７ 周