摘要:

the guidance systemused by the Germans in 1942 in the V–2 missile can be considered to be the first use of inertial navigation. It is true that Foucault defined the gyroscope in 1852 and that Schuler developed the gyrocompass in 1908, but the former device was only a measuring instrument and the latter, although of inertial quality, was only a partial inertial system. The Sperry flight instruments of the late 1920's and early 1930's were attitude–indicating not velocity or position‐indicating devices.Earnest development of inertial navigation systems began in the United States in the late 1940's and early 1950's by the M.I.T. Instrumentation Laboratory, Northrop and Autonetics under Air Force sponsorship. This work led to the inertial guidance systems for ballistic missiles—both land and ship launched. The 1960's brought the Space Age and the advance of inertial guidance in Apollo. During this time inertial guidance systems also found their way into military and then commercial airplanes.Behind the system development was the simultaneous and necessary development of theory, analysis, components, subsystems and testing.The author, whose professional career has been simultaneous with the growth of inertial navigation, draws on his personal experiences in the field of direct association with many of the people and events i

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01262.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

the objective of this paperis to report the latest developments in acoustic underwater navigation. The prime area of concern will be accuracy: first, in the establishment of a transponder navigation field and new techniques for survey of that field; and second, in the determination and study of multipath propagation to limit range errors. Results of in–situ tests to determine characteristics of both interrogation signals and reply signals are presente

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01263.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

accidents at sea, with the concomitant loss of life, material costs and pollution problems, are increasing each year as maritime traffic grows. The use of radar has apparently not entirely controlled this dangerous situation. It would appear that radar, assisted with a supplemental navigational aid with day and night imaging capability, would tend to reduce the possibility for groundings and collisions. A passive day/night LLLTV‐Rangefinder is proposed to provide imagery and range to objects in the vicinity of the ship. Imagery and range in digital format would be displayed on CRTs located on the Bridge or other convenient location. The system would be helpful in night, close‐in navigation by displaying the range and location of buoys, channel markers and landmarks, and be useful in stationkeeping, search, and rescue, etc, and thereby possibly helpful in reducing the number of accidents at sea.With appropriate external optics, the LLLTV camera can be converted into a rangefinder or available rangefinders can be adapted to operate with the LLLTV camera. This paper will also discuss new TV electronics time‐scanning circuitry which eliminates operator mechanical manipulation of rangefinder optics to obtain range. The time scanning techniques will provide rapid, continuous digital range in yards or meters to a computer, LED readouts, and other ancillary recorders as well as

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01264.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

This paper presentsa comparison of the performance characteristics and limitations of the major radio navigation systems which are currently operational or under development. The comparative analysis concentrates on six critical operational parameters which are considered basic to both civil and military applications. These parameters are Volumetric Coverage, Signal Reliability, Accuracy, Data Content, Application Versatility and User Equipment Cost. The ground–based systems analyzed are VORTAC, Loran–C, Omega and Differential Omega. The air–based systems include airborne radar position fixing, Doppler Navigation and the Joint Tactical Information Distribution System (JTIDS) Relative Navigation (RELNAV) function. The satellite–based systems covered are the Navy Navigation Satellite System (NNSS) and the Global Positioning System (GPS). Each of these systems is described and examined on the basis of the six evaluation criteria and a composite system comparison is presented. It is shown that the true cost effectiveness of a navigation system is a strong function of volumetric coverage, data content and application versatility, as well as the more frequently–used parameters of accuracy and signal reliability. The high degree of development maturity of some of the ground–based systems have led to very–low–cost user equipment and this will result in their continued use. The time–synchronous systems, i.e., GPS and JTIDS RELNAV, have unique performance and versatility advantages and these powerful systems will be used widely during the next decades, provided user equipment cost is reduced to acceptable levels. In order to increase over–all cost effectiveness, it is suggested that these latter systems be interconnected so as to take advantage of certain mutually benefic

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01265.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

we present an approachto the Solution of the two body fix which utilizes all of the computing capability of a pocket calculator (non‐programmable). The method results in substantial time savings over the normal approach, either by calculator or by tables, and requires no plotting, no assumed positions, and only a very rudimentary estimate of the navigator's position, the last only for correcting for motion between the times of the two sight

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01266.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Anew method of celestial navigationis presented employing the programable handheld calculator. The technique determines the position of the observer from the “simultaneous” observation of two bodies. The only other information needed is the declination andGHAof the two bodies at their times of observation. It would be possible to determine the position of the observer, without the use of the programable hand–held calculator, with suitable tables. However, it would not have any advantage over the altitude difference method of St.–

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01267.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

a test systemwas assembled to explore the concept of aircraft positioning by combining inertial navigation system data with DME range measurements acquired sequentially from multiple stations. Post–flight processing software was developed using computer simulated data, with many of the predicted performance parameters later confirmed by flight tests. The results indicate that horizontal positioning accuracies of ten to fifteen meters (CEP) and rms velocity errors better than 0.1 meter per second are achievable with the syste

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01268.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01269.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01270.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY