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91.
面向应急条件的多星动态调度方法   总被引:1,自引:0,他引:1  
 针对应急条件下多星动态调度问题,建立了多目标数学规划模型,提出了应急条件多星成像任务合成策略:建立多星多轨任务合成图(MSMOTMG)模型,提出任务合成算法CP-TM。为克服合成导致任务成像机会减少的缺陷,提出了基于合成任务分解的修复技术。此外,为进一步提高调度效率,考虑了任务在等待队列中的向后移位策略,提出了综合考虑任务合成、修复和向后移位的多星动态应急调度(TMRBS-DES)算法。通过大量模拟实验,将TMRBS-DES算法同RBHA算法,以及3个baseline算法(BS-DES、TMR-DES和TMBS-DES)进行了比较。实验结果表明TMRBS-DES算法提高了调度质量,适用于应急条件下多星动态调度问题。  相似文献   
92.
航空器失事等民用运输机场突发事件具有成灾偶发、损失巨大、社会影响强烈的突出特点,高效的应急救援是减少损失、降低社会影响度的重要保障。以GIS桌面软件为平台,建立机场及其邻近区域的机场场道、集结点、道路、消防、医院等地理空间数据库,实现了救援资源的信息化管理和应急救援方案的科学决策,提高了民用机场应急救援水平。  相似文献   
93.
《中国航空学报》2020,33(12):3306-3317
The application of helicopter emergency rescue is becoming increasingly widespread, but the flight crew training in this area is still difficult due to high cost and risk. Nevertheless, with the development of Virtual Reality (VR) technology, virtual simulation has become a significant role in crew training of helicopter rescue. During the implementation of VR-based training, how to transform complex real tasks into VR scenarios and how to evaluate the performance of crew are of great importance. To address these issues, a novel VR-based R-E-A-D (Report, Evaluate, Agree, Do) evaluation model for training is proposed, which is suitable for complex missions with multiple tasks, multiple scenarios, and multiple people. Then, a mapping method of VR scenarios is put forward, which can transform the real tasks into virtual scenarios to serve the virtual simulation training. Finally, an experiment is carried out to verify the feasibility of the evaluation method and virtual scenario mapping method.  相似文献   
94.
王鑫涛  杜星 《航空学报》2020,41(2):223332-223332
多轮多支柱起落架飞机主起落架数量较多,试验机及试验设备重量大。试验应急卸载时,试验件和设备重量、以及加载过程中试验件变形所聚集能量快速释放的不协调性易对支持点结构产生较大冲击载荷,且该载荷不可控,影响试验的考核,存在安全隐患。针对多轮多支柱起落架飞机的强度试验要求,设计一种载荷限定系统。在应急卸载或者试验停试情况下,能够为非支持点起落架输出设定载荷,保证应急瞬间所产生的所有载荷按要求分配到所有起落架上,从而防止支持点起落架超载;试验过程中,能够对非支持点起落架施加试验主动载荷。利用仿真软件验证了系统原理的可行性。依据原理设计载荷限定系统,对其结构和工作性能进行应用验证,并在某型飞机全机疲劳试验中进行应用调试,结果表明,该系统完全能够满足试验要求。  相似文献   
95.
Based on the acoustic mapping, a prediction model for the ground noise radiated from an in-flight helicopter is established. For the enhancement of calculation efficiency, a high-efficiency second-level acoustic radiation model capable of taking the influence of atmosphere absorption on noise into account is first developed by the combination of the point-source idea and the rotor noise radiation characteristics. The comparison between the present model and the direct computation method of noise is done and the high efficiency of the model is validated. Rotor free-wake analysis method and Ffowcs Williams-Hawkings (FW-H) equation are applied to the aerodynamics and noise prediction in the present model. Secondly, a database of noise spheres with the characteristic parameters of advance ratio and tip-path-plane angle is established by the helicopter trim model together with a parametric modeling approach. Furthermore, based on acoustic mapping, a method of rapid simulation for the ground noise radiated from an in-flight helicopter is developed. The noise footprint for AH-1 rotor is then calculated and the influence of some parameters including advance ratio and flight path angle on ground noise is deeply analyzed using the developed model. The results suggest that with the increase of advance ratio and flight path angle, the peak noise levels on the ground first increase and then decrease, in the meantime, the maximum Sound Exposure Level (SEL) noise on the ground shifts toward the advancing side of rotor. Besides, through the analysis of the effects of longitudinal forces on miss-distance and rotor Blade-Vortex Interaction (BVI) noise in descent flight, some meaningful results for reducing the BVI noise on the ground are obtained.  相似文献   
96.
介绍了一种应用于应急搜救的网络化弹跳机器人设计方法。这种机器人采用滚动和跳跃相结合的混合运动模式,可以代替救援人员先行进入到复杂的灾害事故现场搜寻幸存者。机器人之间能够组成ZigBee移动传感器网络,将事故现场的环境状况和幸存者位置等信息通过无线多跳网络及时传回给救援人员,为抢救幸存者赢得时间。实验结果表明, 9cm高的样机以60度角起跳可以腾空30cm以上,水平位移达到70cm,具有较好的越障能力。  相似文献   
97.
载人航天器在压力应急环境下处于低压高浓度氧环境。为了分析该环境下载人航天器在太空中飞行以及地面模拟试验中的着火危险性,研制了低压高浓度氧环境着火试验装置,并进行了燃烧试验。对载人航天器压力应急环境下材料的燃烧速度和点火能量等因素进行分析研究,得到了压力应急工况的材料着火和燃烧的规律,并给出了火灾防范的建议。  相似文献   
98.
爆破切割蒙皮形成应急出口在飞机上的应用国内尚属首次,其最大优点是节省救生准备时间.从爆炸减压、结构变形、结构强度、爆炸反向冲击等方面进行了理论计算,分析了高空爆破切割形成应急出口的可行性.针对切割索弯折过框及长桁降低切割效果问题,进行了摸底试验和余度试验,试验结果表明:只要过框位置切割索弯折后与框距离控制在2~8mm,过长桁位置切割索弯折后与长桁距离不大于2mm,就可以满足切割分离要求,切割索弯折后相互之间不产生影响.通过1∶1地面验证试验,证明了爆破切割蒙皮形成应急出口的可行性,并成功安装于某型飞机上.研究成果可为其他型号采用爆破切割技术提供理论基础和试验数据支持.  相似文献   
99.
《中国航空学报》2021,34(2):554-562
Helicopters are widely used in maritime Search and Rescue (SAR) missions. To ensure the success of SAR missions, search areas need to be carefully planned. With the development of computer technology and weather forecast technology, the survivors’ drift trajectories can be predicted more precisely, which strongly supports the planning of search areas for the rescue helicopter. However, the methods used to determine the search area based on the predicted drift trajectories are mainly derived from the continuous expansion of the area with the highest Probability of Containment (POC), which may lead to local optimal solutions and a decrease in the Probability of Success (POS), especially when there are several subareas with a high POC. To address this problem, this paper proposes a method based on a Minimum Bounding Rectangle and K-means clustering (MBRK). A silhouette coefficient is adopted to analyze the distribution of the survivors’ probable locations, which are divided into multiple clusters with K-means clustering. Then, probability maps are generated based on the minimum bounding rectangle of each cluster. By adding or subtracting one row or column of cells or shifting the planned search area, 12 search methods are used to generate the optimal search area starting from the cell with the highest POC in each probability map. Taking a real case as an example, the simulation experiment results show that the POS values obtained by the MBRK method are higher than those obtained by other methods, which proves that the MBRK method can effectively support the planning of search areas and that K-means clustering improves the POS of search plans.  相似文献   
100.
《中国航空学报》2021,34(2):229-239
This study aims to provide the pilot with optimal control time histories for stabilization of a helicopter after releasing the slung load in aerial delivery missions. A model with 21 degrees of freedom (21-DOF) has been developed and validated for a helicopter slung load system. The control history is generated with detailed procedure based on trajectory optimization. Effects of the objective function formulation on the results are discussed and rules are obtained to assist in the objective function determination. We conclude that the pilot should first decrease and then increase the collective control and adjust the longitudinal control to stabilize the helicopter after the in-hover slung load release. The obtained control history is reasonable and helpful for safety and efficiency improvement. Effects of path constraints and the Flight Control System (FCS) are studied. More stringent path constraints will lead to longer time spent and more controls. Stronger stiffness and weaker damping from the FCS will cause milder control histories but sharper on-axis state histories.  相似文献   
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