Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch

With the aid of multi-agent based modeling approach to complex systems, the hierarchy simulation models of carrier-based aircraft catapult launch are developed. Ocean, carrier, aircraft, and atmosphere are treated as aggregation agents, the detailed components like catapult, landing gears, and disturbances are considered as meta-agents, which belong to their aggregation agent. Thus, the model with two layers is formed i.e. the aggregation agent layer and the meta-agent layer. The information communication among all agents is described. The meta-agents within one aggregation agent communicate with each other directly by information sharing, but the meta-agents, which belong to different aggregation agents exchange their information through the aggregation layer first, and then perceive it from the sharing environment, that is the aggregation agent. Thus, not only the hierarchy model is built, but also the environment perceived by each agent is specified. Meanwhile, the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system （MAS） is resolved. Each agent involved in carrier-based aircraft catapult launch is depicted, with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier, aircraft, and landing gears. The models of reactive agents among them are derived based on tensors, and the perceived messages and inner frameworks of each agent are characterized. Finally, some results of a simulation instance are given. The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely. The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system. This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent, and it is convenient to expand, maintain, and reuse the program codes.

创新战略下的英国研发组织创新--Catapults的组织管理模式研究

Catapults(弹射中心)作为一种新型研发组织形式,在英国创新发展战略的实施中扮演着重要角色。精准的组织功能定位、高效的组织管理运作模式和紧密的网络化组织关系,是Catapults组织管理模式创新的重要三大重要内容。为我国新型研发机构的培育和发展提供了良好的参考样本。

基于CatapultC高层次综合工具平台优化运动检测算法的研究

以视频监控设备作为应用背景,针对全自动视频监控装置能耗高的问题,在硬件So C设计层面,通过利用Catapult C高层次综合工具优化视频算法Sigma-Delta(ΣΔ)的方法以改善电路能耗。即在视频图像中提取有效背景与基准背景进行差分运算,找出运动目标区域并二值处理,使用形态学开运算先腐蚀后膨胀操作以消除区域噪音。实验结果表明,在高层次综合工具平台上同时优化硬件资源与软件算法的方法,能使电路的性能提高9倍,能耗降低9.15倍,达到国际领先水平,满足高性能、低能耗的视频监控电路设计要求。

基于Catapult C的数字滤波算法快速实现

随着光学遥感相机视频数据实时处理算法复杂度的不断增加,直接使用硬件描述语言进行设计难度越来越大,急需引入一种新流程——通过EDA工具直接将高级语言描述转化为HDL语言描述的RTL代码。本设计选择Catapult C工具完成数字滤波算法从C语言到RTL的设计,最后验证经Catapult设计的RTL代码与C、MATLAB功能一致,经硬件实现后性能相当,设计速度比直接使用硬件描述语言快几倍到几十倍。

基于Catapult C的Dsppool设计

在此使用高级语言进行运算加速模块Dsppool描述,再使用Mentor公司的Catapult C工具完成RTL设计,并为Dsppool模块进行满足APB接口的封装,使之能够作为一个AMBA总线上的Slave模块。实验结果显示,使用硬件描述语言手动设计的Dsppool模块与Catapult C设计的RTL代码功能完全一致,并且综合后性能相当,因为高级语言忽略了硬件设计中的细节,设计速度比直接使用硬件描述语言快几倍到几十倍。

基于Catapult C Synthesis的图像校正算法设计

为解决遥感相机在运动过程中的抖动造成的图像位置偏移问题,提出了一种实时图像校正算法。由于在FPGA中采用HDL进行算法设计难度大、开发周期长,故设计中采用了C语言进行算法设计,然后借助Calypto公司的Catapult C Synthesis工具将抽象的C设计转换成硬件RTL代码。在Catapult C Synthesis中对设计的算法进行了C/C++、RLT协同仿真测试,并在Xilinx XC5VLX110T型FPGA上进行了验证。仿真测试及硬件验证结果表明,采用Catapult C Synthesis设计的算法在时序、性能方面均满足设计要求,能够对偏移的图像进行实时校正。

基于Catapult C的DCT算法设计

以DCT(Discrete Cosine Transform)的实现为例,利用Catapult C探索不同的设计架构,快速设计出性能、面积和功耗之间折衷的最佳实现方案,并与传统的手工编写VHDL代码实现方式进行比较。

Dynamics Analysis of Carrier-Based Aircraft with Off-Center Catapult Launch

In order to enhance the safety of the catapult launch of the carrier-based aircraft,the catapult launch multibody dynamic model is established aiming at the problem of off center catapult launch.The whole catapult process including four stages which are buffering,tensioning,releasing and taxiing is taken into consideration and the body dynamics of the off-center catapult during each stage is analyzed.The catapult launch dynamic differences between the conditions only considering taxiing and that considering four stages are compared,and the effects of the different initial off center distances considering four stages on the attitude,landing gear load and acceleration of the carrier based aircraft during catapult launch are discussed.The results show that only considering taxiing may underestimate the dynamics of the carrier-based aircraft substantially.When taking four stages into consideration,the initial off-center distance has small influence on the aircraft dynamic characteristics during buffering and tensioning but has larger influence on that during releasing and taxiing.The increase of the off-center distance will cause the enhancement of the aircraft rolling and yawing,which may lead to the load difference between the left and right landing gears and the increase of the aircraft lateral acceleration.The establishment and simulation of the catapult launch multi body dynamic model founded on buffering,tensioning,releasing and taxiing provide reference for the carrier-based aircraft design and analysis of the catapult launch dynamics.

利用Mentor高层次综合技术(Catapult Synthesis)快速实现复杂DSP算法

为了满足产品上市时间和功能丰富性的要求,越来越多的先进设计公司开始提高设计的抽象层次进行复杂的DSP硬件设计,从RTL级提高到C/C++,以保持产品的持续领先地位。Mentor Graphics的高层次综合工具(Catapult Synthesis)是第一个综合标准的ANSI C++的产品,它可无误地生成针对ASIC/FPGA的高质量RTL代码,且速度比手工编码的快10-20倍。本文以FIR的实现为例,利用Catapult Synthesis快速探索不同的设计架构,快速地找到性能、面积和功耗之间折衷的最佳实现方案,使得真正的IP复用成为可能,并以图表方式给出不同约束下的面积、延迟和吞吐率(36、3、1时钟周期)的性能,同时提供了集成的验证和综合流程,极大地提高了设计效率。

An architecture decomposition method of pneumatic catapult system based on OPM and DSM

The architecture strategy of the Unmanned Aerial Vehicle(UAV)pneumatic launch system should continue to evolve to adapt to complex and variable operating environments.Architecture representation,decomposition perspective,and cluster analysis play a vital role in the early phase of system architecture development.In order for the system to emerge anticipated and desirable intrinsic functional properties,an architecture decomposition method based on the ObjectProcess Methodology(OPM)and Design Structure Matrix(DSM)is put forward in this paper.The OPM is proposed to model the UAV launch process formally,and the matrix representation of the architecture of the pneumatic launch system is established.After the extension of the definition and operations of DSM,with the Idicula-Gutierrez-Thebeau Algorithm plus(IGTA+)clustering algorithm,the transformation of the pneumatic launch system architecture from process decomposition to function decomposition is demonstrated in this paper.The analysis shows that the architecture decomposition of the pneumatic launch system meets the functional requirements of stakeholders.

赋能文化科技融合:战略愿景驱动的公共服务平台建设--英国数字弹射器的运营启示

如何进一步推动文化与科技的深度融合,关系到我国文化产业的高质量发展与文化产业国际竞争力的持续提升。近年来,在税收减免等常规措施之外,公共服务平台作为文化科技深度融合的新型促进手段日益受到各级政府的关注。然而,现有国内相关平台还存在服务体系不完善、创新成果不显著等缺失,以致未能充分发挥出公共服务平台的赋能作用。通过深入考察英国数字弹射器的运营体系,细致阐述其战略愿景、服务体系、运营队伍之“效能三角结构”的内在契合关系,从而为推进国内同类平台的发展提出了针对性的完善建议,丰富了学界对文化科技融合公共服务平台的运营机制探讨。

An optimization model of parameter matching for aircraft catapult launch

To efficiently and fully utilize aircraft carrier resources,an optimization model is presented to deal with parameter matching between aircraft and carrier in the process of aircraft catapult launch.Based on carrier aircraft longitudinal dynamic equations and theorem of kinetic energy in catapult launch course,the work characteristics of different forces are learned and a theory model of parameter matching is deduced.In view of the uncertainty of the model parameters of the theory model and the low matching accuracy of the approximate model,an optimization model of parameter matching is introduced in line with the structure of theory model and the approximate model and is generated by the proposed immune genetic algorithm.Compared with the original genetic algorithm and immune algorithm,the proposed algorithm has better calculation accuracy and convergence.The calculation results show that the optimization model occupies certain application value of engineering estimation from the comparison with the relevant literature data and has higher precision than the approximate models.The validity of the proposed approach is verified with numerical case study on a carrier based aircraft.

基于动力源分类的无人机起飞方式综述

无人机的起飞方式在作战中是个关键因素,决定了无人机作战的灵活性、机动性和高效性等。随着科技的发展,无人机的起飞方式已由最初的滑跑起飞更新换代至多种多样。对无人机起飞方式进行了研究,根据动力源不同将无人机起飞方式分为势能膨胀力作为动力源起飞、电磁力作为动力源起飞、气体反冲力作为动力源起飞和人力作为动力源起飞4大类。对每种无人机起飞方式的工作原理和优缺点进行了详细阐释并列举出了相应的无人机型号,对无人机起飞技术的发展趋势进行了展望。

输电线路覆冰脱冰跳跃抑制措施的仿真研究

覆冰脱落可导致架空线纵向弹跳和动态张力增加,对电力系统的稳定性和安全性构成极大的威胁。首先建立输电导线有限元模型,并通过力学等效进行牵引力及相间间隔棒施加,进而通过数值模拟的方法探究各因素下输电线脱落弹跳抑制措施的效果。结果表明,施加牵引力对导线的弹跳位移和幅值的影响并不显著,不恰当的施加位置反而可能增大闪络风险。加装相间间隔棒对于脱冰弹跳抑制效果明显,其中在导线档中附近加装间隔棒效果最优。强风会导致覆冰导线伴随明显的横向位移,导致更高的闪络风险,而施加间隔棒对导线的横向、纵向位移都有明显的抑制效果,避免闪络事故的发生。

基于磁链观测的永磁直线同步电机自适应非奇异快速终端滑模控制

针对应用于电磁弹射的永磁直线同步电机(PMLSM)无位置传感器控制系统易受参数变化等不确定因素影响,提出一种将磁链观测器与自适应非奇异快速终端滑模控制(ANFTSMC)相结合的组合控制系统。该组合控制系统针对含有不确定参数的PMLSM,设计磁链观测器实时计算电机动子的位置和速度信息,确保控制系统快速获得准确的运行参数,并利用ANFTSMC自适应调整系统收敛速度的特性,抑制不确定因素的影响,提高系统的响应速度,避免终端滑模控制出现的奇异性问题。通过仿真分析验证,该控制系统可以在保证跟踪精度和响应速度的同时,削弱抖振,实现PMLSM无位置传感器情况下快速、平稳运行,该控制系统能够满足电磁弹射的工程应用要求。

考虑航母纵摇的舰载机弹射起飞安全性分析

在弹射起飞的过程中,舰载机的起飞的安全性与多种因素有直接的关系,如剩余甲板长度,前起落架的突伸能力,弹射的冲程等。为了研究多种因素对舰载机弹射起飞的影响,建立了考虑航母纵摇的舰载机弹射起飞动力学模型,分析计算了不同因素对舰载机离舰下沉量的影响,并论述了其运动学成因。研究结果表明:①弹射冲程增大,离舰末速度增大,下沉量减小,反之亦然;②在弹射滑跑转自由滑跑时,前起落架的突伸能力越好,迎角的增量越大,离舰后的下沉量越小,反之亦然;③剩余甲板的长度越长,舰载机离舰的速度和离舰迎角越大,下沉量越小,反之亦然。

电磁发射技术的研究现状与挑战

该文介绍了电磁发射的技术特点和技术分支,归纳了电磁发射系统包含的脉冲储能、脉冲电能变换、脉冲直线电机、检测与控制、高速高过载制导五项共性技术,综述了电磁发射在军事平台和武器领域、民用及航天领域的发展现状及应用情况,指出了目前面临的挑战及对策,提出了电力电子系统无缆化、高性能材料复合化、全系统感知控制智能化的发展趋势,旨在为电磁发射技术的后续研究提供参考。

考虑泄漏的无杆式高压气动弹射器内弹道精确建模及试验

无杆式高压气动弹射器因开口的固有结构决定其存在一定量的泄漏,为此设计并开展样机泄漏测试试验。基于由实验数据拟合的标准干空气热力学状态方程,分别按理想气体和真实气体对比计算泄漏率,并拟合泄漏率随压力、行程变化的经验公式。建立考虑动态泄漏、真实气体效应及真实开阀规律的精确内弹道模型,对考虑和不考虑泄漏两种工况的结果进行对比,并详细分析考虑泄漏的弹射过程中热力学参数与负载运动参数的变化规律,将其与弹射试验数据、流体仿真结果进行对比。研究结果表明:按理想气体计算的泄漏率比真实气体偏小约4%;泄漏率不超过4%/s;考虑泄漏的精确内弹道模型计算结果与弹射试验数据、流体仿真结果均基本一致,具有较高的计算精度。