椭圆参考轨道指定区域最优交会研究

研究了椭圆参考轨道指定区域最优交会问题。为了实现在指定区域完成最优交会,采用以参考轨道真近点角为自变量的线性化时变Tschauner-Hempel交会动力学模型,按照设定的真近点角交会域和最优二次性能指标设计最优交会控制,加权矩阵随真近点角变化。为方便指定区域最优控制问题求解,采用区段混合能法递推求解时变黎卡提矩阵微分方程和状态轨线。对远距、近距异面交会和共面交会三种情况设定不同的交会域进行了仿真研究,结果表明方法能保证在设定的真近点角域内完成交会,交会控制能耗小,精度高。     

近景大视场角分区域标定方法研究

针对飞行试验测量视场大相机标定精度低的问题,提出一种高精度CCD相机分区域标定方法。该方法首先通过将标靶均匀布置在摄像机视场内,使得标靶尽可能均匀错落地充满整个视场范围,再结合人眼判读的方式求解靶标的像面位置,最终与全站仪三维坐标形成精确的空间标定点集。接着,将像平面按横向方向等间距分割成Ｎ个区域,并结合后方交会的方法分别对每个子区域进行相机参数的计算。实验结果表明：经过分区域标定,相机采集点的总误差比单区域标定法降低了4％(Ｎ＝3)。算法可实现指定区域的相机参数计算,基本满足中高等精度的工业测量要求。所本文研究可应用于位置相对固定不变的工业视觉测量,特别是大工件测量领域。     

PIM-SM注册报文发送的分布式实现

针对指定路由器向汇聚点路由器注册过程中,主控生成报文数量过多对路由器造成负担太大的问题,提出分布式注册报文发送的实现方案,其主要包括理论分析与仿真测试。结果证明该方法减轻了主控的处理负担,缩短了数据包在路由器里的平均处理时间,减少了主控与底层信息交互的次数。     

关于Hill方程的一点思考

对近圆相对运动中Ｈｉｌｌ方程的精度进行了理论分析，指出Ｈｌｉｉ方程的发散性是由于没有计及非线性影响造成的。给出了Ｈｉｌｌ方程的改进形式，仿真表明，改进形式比经典Ｈｉｌｌ方程更符合实际情况。     

交会对接仿真系统的原型技术研究

研究了在交会对接仿真系统中应用原型技术的方法,分析了交会对接仿真系统的系统需求,概述了原型法的一些基本概念,研究了面向对象技术和原型技术的融合问题,分析了基于面向对象的原型法在交会对接仿真系统中的应用问题,并在最后建立了一个交会对接仿真系统的进化型原型框架.对此原型框架的仿真表明,原型法在交会对接仿真系统中的应用是成功的.     

Rendezvous of multiple nonholonomic unicycles-based on backstepping

Rendezvous problem of nonholonomic unicycles has been considered in this paper and nonlinear distributed controllers based on backstepping are constructed to guarantee the consensus of both position and direction simultaneously. Cascaded theory of nonlinear system is utilised to reduce the rendezvous problem of nonholonomic unicycles to consensus problem of moving direction and consensus problem of position, respectively. The uncontrollable challenge of position system after consensus of moving direction has been successfully removed through dilated coordinate transformation. Then, a modified backstepping methodology based on the coupling structure of position system is derived to guarantee the consensus of each unicycle's position. In the end, not only consensus of position but also consensus of direction has been realised for multiple nonholonomic unicycles using the controllers proposed in this paper. Simulation results using Matlab illustrate the effectiveness of the results of this paper.     

双站交会角的单站虚拟观测

利用程差的相似递推,并通过和由正弦定理所得到的三角函数式联解,可得到含有未知主站径向距离的双站交会角的单站测算方程。在此基础上,进一步利用短距相差测距法,给出了基于相差测量的双站交会角的单站测算公式。由于仅和主站的参数测量相关,故副站以及双站间的间距实际上可以是虚设的。误差分析表明,由于所得到的交会角测算式与径向距离成反比,所以,基于短基线相差检测所得到的双站交会角可具有较好的测量精度。     

An SR approach to multiway rendezvous

This paper presents a new approach to programming multiway rendezvous problems in the SR language. The approach uses SR's concurrent invocation statement and rendezvous mechanism to coordinate the interacting processes. This approach is compared with one that suggested an extension to SR's rendezvous mechanism. The two approaches result in differing program structure. The new approach is shown to lead to simpler and cleaner interfaces between the main process and the worker processes, and uses only existing language mechanisms. The results are of importance to both programmers and designers of concurrent program languages.     

Remote rendezvous

BNR Pascal is a systems programming language intended for the implementation of the systems software of distributed computing systems. It supports the Ada Rendezvous model of tasking and communication, uniformly extended to support communications between tasks distributed over the computing nodes of a system. BNR Pascal was designed and implemented in 1980, and has since been used to implement the operating systems and real-time applications software for Northern Telecom's Meridian family of products. In total, more than 2 million lines of BNR Pascal exist. This paper describes the BNR Pascal remote rendezvous: the extension of rendezvous to interprocessor communication. It discusses the implementation of remote rendezvous, describing the advantages and disadvantages of several options. Finally, it details BNR's experience in using remote rendezvous in building substantial, practical distributed systems used in products.     

空间交会对接多自由度仿真器

本文首先研究和分析国外交会对接仿真经验，并经述有关交会对接的目的与要求。其次提出一种新的多自由度交会对接仿真器方案，它比起 类型仿真器投资造价将要降低４￣５倍。