词条 | 着陆引导系统 |
释义 | 基本简介着陆引导系统(landing guidance system) 用无线电设备引导驾驶员或自动驾驶仪使飞机安全着陆的导航系统。无线电着陆引导系统向飞机提供精确的着陆方位、下滑道和距离等引导信息,飞机依据这些信息对准跑道并按给定的下滑角进场和着陆,以保证接地点的偏差在规定的范围以内。 基本分类着陆系统有以下3种 ①仪表着陆系统在各种气象条件下,驾驶员凭借仪表使飞机安全着陆的无线电导航系统。这种系统最早出现于1939年,1949年国际民航组织将其定为国际标准着陆系统。它的优点是:能在复杂气象条件下提供精确直观的引导着陆信息;可根据气象和机场条件选择不同的工作类型(决断高度和跑道视距);使用国际通用的标准设备。缺点是:只能提供一条下滑角固定不变的对准跑道中心线的进场着陆航道,不适用于短距起落和垂直起落的飞机;通道少(40个),不能满足国际民航的新要求(200个);系统要求平坦和净化的场地(草、雪等都会影响引导信号质量)。因而国际民航组织规定这类系统使用保护期截止到1995年1月1日。 ②地面控制进场系统能准确地测量进场和着陆过程中飞机位置并引导着陆的雷达系统。其优点是:机上无需加装电子设备,对驾驶员无需进行特殊训练;适用于各种场地,机动性好;根据不同机种对下滑角度的要求可选择不同的下滑线。缺点是:因靠地面管制员指挥,驾驶员工作被动;靠管制员手控天线跟踪飞机,只能一架一架地引导;引导距离受气象条件限制。但它不断采用新技术,这些缺点正在克服中。 ③微波着陆系统工作于微波频段(5031.0~5090.7兆赫)、由机上设备获得引导数据的无线电着陆系统。其优点是:系统精度高,能满足全天候工作要求;允许飞机任意选择机场航道,适用于作各种起落的各型飞机;系统容量大(200个通道),能满足空中交通量增加的要求;设备体积小,对场地要求低;系统抑制多径干扰能力强。国际民航组织于1978年选定时基扫描波束微波着陆系统作为新的标准着陆系统。它能提供连续的、精确的3坐标(方位、仰角、距离)信息。 阿波罗的AGC在月球轨道上的每个航班任务的月亮(有一个例外的阿波罗8号登月舱,而没有考虑)有,分别在两个游戏机中心的指令舱和登月舱 。 The AGC in the Command Module was at the center of that spacecraft's guidance & navigation system (G&C).在命令模块的AGC是中心,在飞船的指导及导航系统(G及丙类)。 The AGC in the Lunar Module ran its Primary Guidance, Navigation and Control System , called by the acronym PGNCS (pronounced pings ).该模块的AGC运行在农历其主要指导方针,导航和控制系统 )的缩写省地名委员会所要求的(发音坪 。 Each lunar mission had two additional computers:每一个月球的任务有两个额外的计算机: The Launch Vehicle Digital Computer (LVDC) on the Saturn V booster instrumentation ring, and该运载火箭数字计算机(LVDC)对土星五号助推器仪器戒指, the Abort Guidance System (AGS) of the Lunar Module, to be used in the event of failure of the LM PGNCS.在中止制导系统(AGS)的登月舱,将用于省地名委员会的活动LM滚动失败的。 The AGS could be used to take off from the Moon, and to rendezvous with the Command Module, but not to land.的AGS可用于从月球起飞,并与指令舱会合,而不是土地。 设计自动增益控制的目的是在麻省理工学院实验室仪器下的Charles Stark Draper ,硬件的设计与领导埃尔登三馆 。 早期的建筑作品来自JH拉宁小阿尔伯特霍普金斯 , 拉蒙阿隆索 , [2]和休布莱尔,史密斯 。 [3]这次飞行是由硬件制造雷声公司 ,其香草泰勒 [4]的研究小组还对建筑。 The Apollo flight computer was the first to use integrated circuits (ICs) .阿波罗飞行计算机是第一个使用集成电路)集成电路( 。 While the Block I version used 4,100 ICs, each containing a single 3-input NOR gate , the later Block II version (used in the crewed flights) used 5,600 ICs, each with two 3-input NOR gates. :34 The ICs, from Fairchild Semiconductor , were implemented using resistor-transistor logic (RTL) in a flat-pack .虽然我的版本用4100块输入集成电路,每个包含一个单一的3 或非门 ,后来的第二座版本(载人飞行中使用的)使用5600芯片,盖茨每两个3输入或非。 :34从集成电路, 仙童半导体公司 ,实施了利用电阻晶体管逻辑 )在(RTL的扁平封装 。 They were connected via wire wrap , and the wiring was then embedded in cast epoxy plastic.他们通过连接线包装 ,电线和当时投嵌入在环氧树脂胶。 The use of a single type of IC (the dual NOR3) throughout the AGC avoided problems that plagued another early IC computer design, the Minuteman II guidance computer , which used a mix of diode-transistor logic and diode logic gates. AGC的使用类型单一双NOR3)在整个集成电路(避免问题的困扰另一个早期计算机集成电路的设计, 民兵Ⅱ 指导计算机 ,它使用了混合二极管,晶体管逻辑和二极管逻辑门。 软件当为自动增益控制的设计要求的定义,必需的软件和编程技术,以便它不存在,必须从头设计的。 AGC software was written in AGC assembly language and stored on rope memory .自动增益控制AGC的软件是写在汇编语言和存储绳记忆 。 There was a simple real-time operating system consisting of the Exec , a batch job-scheduling system that could run up to 8 'jobs' at a time using cooperative multi-tasking (each job had to periodically surrender control back to the Exec).有一个简单的实时操作系统组成的Exec的工作,批处理作业调度系统,可8'工作'在运行时使用最多的合作多任务(每人都必须定期交出控制权返回给Exec的) 。 There was also an interrupt-driven component called the Waitlist which could schedule multiple timer-driven 'tasks'.还有一个中断驱动的组件称为候补可安排多个定时器驱动的'工作'。 The tasks were short threads of execution which could reschedule themselves for re-execution on the Waitlist, or could kick off a longer operation by starting a 'job' with the Exec.执行的任务都是可以重新安排重新对自己的候补执行,短期或将引发线程通过启动一个'工作与执行'一个较长的运作。 The Exec jobs were priority-based.这位管理工作是基于优先级的。 The lowest priority job, called the dummy job, was always present.最低的优先工作,被称为虚拟工作,是始终存在。 It did diagnostic checks and controlled a green computer activity light on the DSKY: If the dummy job was running, this meant the computer had nothing better to do, so the light was turned off.它确实诊断检查和控制活动光照对DSKY绿色电脑 :如果正在运行的虚拟工作,这意味着计算机有没事做,所以灯关闭。 The dummy job exited if there was some higher priority job to be done and this was indicated by the computer activity light being illuminated.如果退出的虚拟工作有更高的优先处理的工作要做,这是由计算机活动指示灯提示被照亮。 The AGC also had a sophisticated software interpreter, developed by MIT, that implemented a virtual machine with more complex and capable pseudo-instructions than the native AGC. AGC的也有复杂的软件翻译,由麻省理工学院开发的,即实施更复杂,有能力的伪比本土的AGC指令虚拟机。 They were used for navigational computations where greater precision was required.他们在那里被用于更精确的计算,需要航行。 Interpreted code, which featured double precision scalar and vector arithmetic, even an MXV (matrix × vector) instruction, could be mixed with native AGC code.解释代码,其中精选双精度标量和矢量运算,甚至是MXV (矩阵×向量)指令,可与本机的AGC混合代码。 While the execution time of the pseudo-instructions was increased (due to the need to interpret these instructions at runtime) the interpreter provided many more instructions than AGC natively supported and the memory requirements were much lower (memory capacity was very expensive at the time).虽然伪指令的执行时间增加(由于需要在运行时解释这些指令)的解释提供了很多详细说明,比原生支持自动增益控制和内存的要求明显降低(内存容量为当时非常昂贵) 。 The average pseudo-instruction required about 24 ms to execute.平均伪指令需要约24毫秒执行。 The assembler and version control system, named YUL for an early prototype Christmas Computer [ 5 ] , enforced proper transitions between native and interpreted code.汇编器和版本控制系统,命名为原型栗早日圣诞计算机 [5] ,执行代码正确理解和本土之间的过渡。 A set of interrupt-driven user interface routines called Pinball provided keyboard and display services for the jobs and tasks running on the AGC. A接口设置中断驱动的用户提供日常所谓弹球在AGC运行键盘和显示服务的工作和任务。 A rich set of user-accessible routines were provided to let the operator (astronaut) display the contents of various memory locations in octal or decimal in groups of 1, 2, or 3 registers at a time. Monitor routines were provided so the operator could initiate a task to periodically redisplay the contents of certain memory locations.阿访问的例程丰富的用户提供了让经营者(宇航员)显示的内容,地点不同的记忆八进制或十进制寄存器,在组1 2或3,在规定的时间。 监视器例程是如此的经营者可以发起一个任务来定期重新显示某些内存位置的内容。 Jobs could be initiated.乔布斯可能会启动。 The Pinball routines performed the (very rough) equivalent of the UNIX shell.该弹球例程进行的UNIX外壳(非常粗糙)相同。 |
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