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[[File:Voskhod spacecraft IMP 'Globus' navigation instrument, full view.jpg|thumb|right|upright=0.9|IMP ''Globus'' instrument]]
'''Globus IMP instruments''' were [[Engineering:Spacecraft|spacecraft]] [[Earth:Navigation|navigation]] instruments used in Soviet and {{wipe|Russia}}n crewed spacecraft. The IMP acronym stems from the Russian expression ''Indicator of position in flight'', but the instrument is informally referred to as the ''Globus''. It displays the [[Nadir|nadir]] of the spacecraft on a rotating terrestrial globe. It functions as an onboard, autonomous indicator of the spacecraft's location relative to Earth coordinates.<ref name="Siddiqi01">{{cite book|last=Siddiqi|first=Asif|title=Sputnik and the Soviet Space Challenge|date=2003|publisher=University Press of Florida|location=US|isbn=978-0-8130-2627-5|page=196}}</ref> An electro-mechanical device in the tradition of complex post-[[Social:World War II|World War II]] [[Physics:Clock|clock]]s such as [[Engineering:Master clock|master clock]]s, the ''Globus'' IMP instrument incorporates hundreds of mechanical components common to horology. This instrument is a [[Mechanical computer|mechanical computer]] for navigation akin to the [[Norden bombsight]]. It mechanically computes complex functions and displays its output through mechanical displacements of the globe and other indicator components. It also modulates electric signals from other instruments.

The IMP, in successively developing versions, has been used in Soviet and Russian [[Astronomy:Human spaceflight|crewed space missions]] ever since the world's first crewed spaceflight ([[Biography:Yuri Gagarin|Yuri Gagarin]], 12 April 1961) through every crewed [[Astronomy:Vostok programme|Vostok]], [[Astronomy:Voskhod programme|Voskhod]] and [[Engineering:Soyuz programme|Soyuz]] mission until 2002.
:''This article specifically covers IMP Version 3, used in [[Astronomy:Voskhod 1|Voskhod 1]], since Version 3 has been more extensively documented than earlier versions used during the Vostok missions and subsequent versions for the more complex [[Engineering:Soyuz programme|Soyuz]]. However all versions of the IMP were relatively similar with respect to design, purpose and operation.''

==Context and purpose==
[[File:Vostokpanel.JPG|thumb|upright=0.9|A IMP ''Globus'' instrument within the Voskhod navigation panel]]

The Voskhod spacecraft was the second generation of spacecraft designed in the crewed [[Astronomy:Soviet space program|Soviet space program]], essentially an adaptation of the earlier Vostok spacecraft. It flew two crewed missions, [[Astronomy:Voskhod 1|Voskhod 1]] (world's first multi-crewed mission, launched on 12 October 1964) and [[Astronomy:Voskhod 2|Voskhod 2]] (featuring the world's first Extra-vehicular activity, or EVA, commonly called a ''spacewalk'', launched on March 18, 1965). The Voskhod spacecraft—and its ''Globus'' IMP instruments—is a close derivative of Vostok, which flew six Soviet individuals to [[Astronomy:Low Earth orbit|low Earth orbit]], including the world's first human in space, Yuri Gagarin, and the world's first woman in space, [[Biography:Valentina Tereshkova|Valentina Tereshkova]]. The main difference between IMP versions 1 and 2 (Vostok spacecraft) and later versions (Voskhod and Soyuz) is the addition of the disc-shaped longitude and latitude indicators.<ref name="Yurii01">{{cite web|last=Тяпченко (Tiapchenko)|first=Юрий Александрович (Yurii A.)|title=Information Display Systems for Russian Spacecraft: An Overview|url=http://web.mit.edu/slava/space/essays/essay-tiapchenko1.htm|work=Computing in the Soviet Space Program (Translation from Russian: Slava Gerovitch)}}</ref><ref name="Yurii02">{{cite web|last=Тяпченко (Tiapchenko)|first=Юрий Александрович (Yurii A.)|title=Системы отображения информации космических кораблей "Восток" и "Восход"|url=http://www.astronaut.ru/bookcase/article/article130.htm?reload_coolmenus}}</ref>

The design objectives for the IMP were to compute and display the geographic coordinates at the spacecraft's [[Nadir|nadir]], i.e. which point on Earth's surface it was overflying. The Globus displayed this data to the crew, and also transmitted electrical data to other systems through a variable resistance and cam-activated switching.<ref name="SiddiqiASC">{{cite book|last=Siddiqi|first=Asif|title=Sputnik and the Soviet Space Challenge|date=2003|publisher=University Press of Florida|location=US|isbn=978-0-8130-2627-5|pages=200, 201}}</ref><ref name="KyraPanels">{{cite web|last=Collins|first=Amy Kyra|title=The Panels of the Spacecraft ''Vostok''|url=http://vostoksupersite.weebly.com/index.html|work=Vostok Control and Instrument Panel Site СОИ кк «Восток»}}</ref>{{citation needed|date=October 2011}}

Derivatives of Vostok's and Voskhod's IMP have been flown on every Soyuz spacecraft up to the last of the [[Engineering:Soyuz TM|Soyuz TM]] mission in April 2002. The main functional addition to IMP versions designed for Soyuz was the ability to manually change the orbit inclination. On Vostok and Voskhod, the inclination to the equator had been constant at 65 degrees by virtue of the [[Engineering:Booster (rocketry)|booster]] design limitations and the geographical location of the Baikonur Cosmodrome from which every Soviet and Russian crewed mission had been launched to date, so there was no need to implement inclination modulation into versions 1 to 4 of the IMP.{{citation needed|date=October 2011}}

The [[Engineering:Soyuz TMA|Soyuz TMA]] spacecraft and its successors now provide similar functions to the ''Globus'' using a computerized world map on a computer display.<ref name="Yurii03">{{cite web|last=Tiapchenko|first=Yurii |title=Information Display Systems for Russian Spacecraft: Generations III, IV and V|url=http://web.mit.edu/slava/space/essays/essay-tiapchenko3.htm|work=Computing in the Soviet Space Program (Translation: Slava Gerovitch)}}</ref>

The Russian early missions were mostly automated and controlled from the [[Engineering:Mission control center|mission control center]] (the [[Engineering:Mission control center#RKA Mission Control Center|''TsUP'']]). The spacecraft essentially controlled itself, and the [[Biography:Cosmonaut|cosmonaut]]s were expected to initiate maneuvers or corrections only after approval from the MCC and according to its data and parameters. Therefore, the instrumentation available to the pilot was minimal and its operational relevance was limited to contingency scenarios as much as possible. The readings from the IMP were primarily intended to help cosmonaut pilots confirm that the automated flight sequencer was operating normally. The data would also keep the crew aware of their position when they were orbiting over the nighttime part of the Earth, or when the spacecraft's viewports and ''Vzor'' periscope couldn't be pointed toward the ground.{{citation needed|date=October 2011}}

However, the IMP would become crucial if manual [[Engineering:Retrorocket|retrorocket]] activation became compromised by failure of either the flight sequencer or communications with mission control, as did happen on [[Astronomy:Voskhod 2|Voskhod 2]]. Furthermore, given the scarcity of Soviet communication stations on Earth, the cosmonauts spent most of their time out of range with ground control and needed instruments to assess their position relative to the ground.<ref name=Siddiqi01/><ref name="ErpiAn">{{cite book|last=Sparrow|first=Giles|title=Space Flight|url=https://archive.org/details/spaceflightcompl00spar|url-access=limited|date=2007|publisher=Dorling Kindersley|location=UK|isbn=978-0-7566-5641-6|pages=[https://archive.org/details/spaceflightcompl00spar/page/n319 320]}}</ref><ref name="ErpiFr">{{cite book|last=Sparrow|first=Giles|title=conquête de l'espace (La)|date=2008|publisher=E.R.P.I.|location=Canada|isbn=978-2-7613-2726-8}}</ref>

By contrast, the US crewed space programs used a similar, mechanical positional indicator only during two of its early Mercury missions before discarding it. By 1961 under project [[Astronomy:Project Gemini|Project Gemini]] the US crewed space program changed to fully autonomous digital computerized systems. These systems consisted of gyro platform, digital computer and fly-by-wire systems.<ref>NASA C-119162 Project Gemini Familiarization Manual, 1963, McDonnell, https://www.ibiblio.org/apollo/Documents/GeminiManualVol1Sec2.pdf </ref> The first being the Gemini Guidance Computer. The computer was architecturally similar to the Saturn [[Engineering:Launch Vehicle Digital Computer|Launch Vehicle Digital Computer]], in particular in the instruction set; however its circuit integration was less advanced.<ref>NASA C-119162 Project Gemini Familiarization Manual, 1963, McDonnell, https://www.ibiblio.org/apollo/Documents/GeminiManualVol1Sec2.pdf </ref><ref>CR-123823, 63-928-130, "IBM Apollo Study Report, Volume II: LVDC", volume II of II, 10/01/1963, by IBM Federal Systems Division https://www.ibiblio.org/apollo/Documents/IBMStudyReport-63-928-130-Volume2.pdf </ref> Later , for the [[Astronomy:Apollo program|Apollo program]] NASA, under the lead of MIT's Instrument Laboratory will use the fist digital computer using integrated circuits, the [[Engineering:Apollo Guidance Computer|Apollo Guidance Computer]].<ref name="Hall-1996">{{Citation | first = Eldon C. | last = Hall |  title = Journey to the Moon: The History of the Apollo Guidance Computer | place = Reston, Virginia, USA | publisher = [[Organization:American Institute of Aeronautics and Astronautics|AIAA]] | year = 1996 | page = 196 | isbn = 1-56347-185-X }}</ref><ref>{{cite book |last1=Butrica |first1=Andrew J. |chapter=Chapter 3: NASA's Role in the Manufacture of Integrated Circuits |editor-last1=Dick |editor-first1=Steven J. |title=Historical Studies in the Societal Impact of Spaceflight |date=2015 |publisher=[[Organization:NASA|NASA]] |isbn=978-1-62683-027-1 |pages=149–250 |url=https://www.nasa.gov/sites/default/files/atoms/files/historical-studies-societal-impact-spaceflight-ebook_tagged.pdf}}</ref>

==Structure and materials==
[[File:Voskhod spacecraft IMP 'Globus' navigation instrument, inside view.jpg|thumb|upright=0.9|IMP ''Globus'', inside view]]

Two main instrument panels were used for Vostok and Voskhod: a control panel with switches and rotary controllers, and an instrument display panel (IDS, for Instrument Display System).<ref name=Yurii01/> On Vostok and Soyuz spacecraft, the IDS Panel sits in front of the cosmonauts, above the ''Vzor'' periscope screen. As for Voskhod 1 and Voskhod 2 however, mission design compromises forced upon the designers for [[Astronomy:Soviet space program|propaganda motivations]]<ref name=Siddiqi01/> had the cosmonauts' seats rotated 90 degrees clockwise, making the reading and setting of the IDS panel less convenient.{{citation needed|date=October 2011}}

Designed to be integrated into a niche in the instrument display panel, the IMP instrument's volume was about that of a big toaster [Width: 24.8&nbsp;cm({{frac|9|3|4}} in), H:22.2&nbsp;cm ({{frac|8|3|4}} in), D:14.6&nbsp;cm({{frac|5|3|4}} in)]. It was the prominent feature of the IDS panel. The front panel of the IMP instrument served as the structural support for all other components; it was made of thick, machined aluminum alloy with structural protrusions.{{citation needed|date=October 2011}} The mechanical components were made of brass, steel and aluminum; the globe itself was made of aluminum covered with printed paper, a [[Globe#Manufacture|typical technique for the manufacture of terrestrial globes]]. The enclosing cover was made of a sheet of aluminum alloy cut and soldered to shape.{{citation needed|date=October 2011}}

Like most of early spacecraft's cockpit instruments, the IMP ''Globus'' was designed and tested to remain operative in a complete vacuum, in case of an accidental depressurisation of the cabin.

==Displays and settings==
[[File:Voskhod spacecraft IMP 'Globus' navigation instrument, front view.jpg|thumb|right|upright=0.9|Displays and settings]]

===Displays===
* A terrestrial globe, with a diameter of 12.7&nbsp;cm (5&nbsp;inches),{{citation needed|date=December 2012}} which approximate a 1:100,000,000 scale, moving in two degrees of freedom (rotation and inclination);
* Two disc-shaped indicators, one each for longitude and latitude, with markings in degrees on their edges;
* An orbit [[Mechanical counter|counter]] labelled ''ЧИСЛО ВИТКОВ'' (Number of revolutions) with three digits: two white digits for orbits and one red digit for fraction of an orbit;
* A backlit indicator below the globe that, when illuminated, displayed the text ''МЕСТО ПОСАДКИ'' (Landing Place).

===Pilot settings===
* One switch (on the separate Control panel) activates the instrument;<ref name=KyraPanels/>
* One switch (on the separate Control panel) activates a motor which displaces the indicators from the actual position relative to the Earth to the projected point of landing position, or vice versa<ref name=KyraPanels/>
* Two concentric knobs conjointly labelled ''КОРРЕКЦИЯ'' (Correction). The inner knob is simply labelled ''С'', ''П'' and ''Л'' (Center, Right and Left). Selecting one of these three positions mechanically assigns the outer knob, labelled ''НАПРАВЛЕНИЕ ВРАЩЕНИЯ'', ''МЕНЬШЕ'' and ''БОЛЬШЕ'' (Direction of rotation, Less and More) to preset one of three [[Astronomy:Orbital elements|orbital parameters]]; and three corresponding one-digit indicators;<ref name=KyraPanels/>
* One knob marked ''Э'' presets or resets the indicators longitude position, i.e. in the equatorial plane;<ref name=KyraPanels/>
* One knob marked ''О'' presets or resets the indicators' position along the orbit;<ref name=KyraPanels/>
* One knob (missing in the picture) presets or resets the orbit counter.

==Functions displayed==
[[File:Voskhod spacecraft IMP 'Globus' navigation instrument. Globe with Earth communication station indicators.jpg|thumb|right|upright=0.9|Globe with numbered bullets indicating Earth communication stations]]

The moving terrestrial globe was protected by a hemispherical transparent plastic dome, on which was engraved and printed a cross-shaped sight. Under normal operations, the point visible under the cross was the point on Earth which was directly under the spacecraft at any given time. A second mode of operation, activated by the cosmonauts, advanced the globe to a position where the spacecraft would land should the retrorockets be fired at that moment to effect the reentry sequence, which also lit the ''место посадки'' indicator. The latitude and longitude indicators followed these two modes of operation as well.<ref name=Yurii01/>

At least one Voskhod IMP's globe was customized with white paper bullets numbered from 1 to 8, along with unnumbered bullets.<ref name="cSGlobus">{{cite web|author=music_space|title=''Researching and exhibiting Voskhod Globus''|url=http://www.collectspace.com/ubb/Forum14/HTML/000733.html|work=Hardware & Flown Items}}</ref> Those relate to radio communication centers linked with Mission Control in Moscow. The unnumbered bullets refer to [[Engineering:Tracking ship|space control-monitoring ships]].<ref name=cSGlobus/><ref name="KyraGround">{{cite web|last=Collins|first=Amy Kyra|title=Ground support|url=http://vostoksupersite.weebly.com/ground-support.html|work=Amy's Spacecraft Vostok Control and Instrument Panel Site СОИ кк «Восток»}}</ref>

==Operation==
Prior to launch, latitude and longitude were adjusted to the precalculated coordinates of entering orbit. Right after the [[Engineering:Spaceflight#Launch|launch phase]], once the orbit was established, its parameters were precisely measured by radar and radio telemetry from the ground. Revised settings for the IMP were then computed on the ground and communicated to the crew, which reset the instrument's three orbital ''Correction'' parameters, the equatorial longitude and the present point in the orbit using the two ''КОРРЕКЦИЯ'' knobs, the ''Э'' knob and the ''О'' knob. After this, the cosmonauts toggled the activation switch on the left-side Control panel. This last action connected the flight sequencer system's impulses to the instrument's solenoid actuator. These impulses were then converted into a slow, regular mechanical advance which cascaded through the mechanical components, effecting the computations needed to move the globe and other indicators.{{citation needed|date=October 2011}}

Meanwhile, the instrument's variable resistor and cam-activated electric blade contacts modulated electrical signals from other electrical instruments through the spacecraft and its control systems, feeding them with an analog representation of the spacecraft's displacement relative to Earth coordinates. From a systems design perspective, it is remarkable, even in the early 1960s, that a mechanical system generated crucial, primary data to electrical and electronic control and telemetry systems through the spacecraft.<ref name=cSGlobus/>

During orbital operations, the crew periodically resynchronized the instrument's readings with ground-generated data during communication passes. On a Soyuz mission, the spacecraft has the added capability to do [[Astronomy:Orbital maneuver|orbital maneuver]]s, and the orbital parameters on the IMP instrument had to be changed accordingly for each maneuver.{{citation needed|date=October 2011}}

When the critical operation of deorbit retrorockets burn was approaching in preparation for [[Astronomy:Atmospheric entry|atmospheric entry]], the crew monitored the automatic orientation of the spacecraft (a function of the attitude control system), then toggled the proper switch on the Control panel to "fast-forward" the IMP instrument in order to display the projected point of landing. The crew then stood ready to effect a manual deorbit burn if the automatic systems failed to work.{{citation needed|date=October 2011}}

==Mechanical computer==
The IMP was a genuine [[Mechanical computer|mechanical computer]]. From the sole solenoid actuator's incremental motion, the horological mechanism derived irregular oscillating functions which in turn rotated the globe and varied its axis, and also moved its two cylindrical indicators for longitude and latitude. Some uncommon, intricate horological devices found in the IMP include [[Cardioid|cardioid]]-shaped cam discs, a cone-shaped cam cylinder with a cardioid cross-section and "mechanical rectifiers" which transformed an alternating motion into an analogous, but unidirectional motion (see illustrations).

The only other electric actuator used in the IMP instrument was the motor used to fast-forward the mechanism from the actual point-to-nadir to the expected landing point, some 120 degrees further east.<ref name=Yurii02/>

==Production, conservation and public display==
A few dozen specimens at most of the Voskhod ''Globus'' instrument Versions 3 and 4 were built, including the two flown during the ''Voskhod 1'' and ''Voskhod 2'' missions, test articles and units flown in unmanned missions. Many of them are exhibited in various [[Engineering:List of aerospace museums#Russia|Russian aerospace museums]] (sometimes mislabelled as ''Vostok'' IMP instruments), while a few are known to be in individuals' space-related artifact collections. Furthermore, an unknown number of units may still belong to former Soviet space workers' and officials' estates. The Smithsonian Institution's National Air and Space Museum in Washington DC (US) exhibits several Soyuz spacecraft whose ''Globus'' are still in place, but their instrument panels are not visible to visitors. The museum also displays a [[Engineering:TKS (spacecraft)|TKS spacecraft]] with a Soyuz-version of the IMP instrument, whose panels and the ''Globus'' can be glimpsed through the porthole.

Space-related artifacts are available for purchase on [[Finance:Online auction|online auction sites]], on specialized auctions and through specialized dealers. However, items such as ''Globus'' instruments rarely come on the market.<ref name=cSGlobus/>

One specimen of a Voskhod ''Globus'' IMP instrument have been the property of Canadian space-related artifact collector François Guay. It is now (2020) owned by one of the premier space hardware collectors in the world, based in the United States.<ref name="CSpage02">{{cite web|title=Topic: Researching and exhibiting Voskhod Globus (look for SpaceAholic)|url=http://www.collectspace.com/ubb/Forum14/HTML/000733.html}}</ref> It has been exhibited in temporary exhibitions, notably the National Watch and Clock Museum in Columbia, Pennsylvania, US,<ref name="NwcmExhibit">{{cite web|title=Time & Exploration Exhibit - NWCM|url=http://www.authorstream.com/Presentation/nwcm-197908-time-expl-Education-ppt-powerpoint|page=52}}</ref> and at the Space Science Center of the [[Organization:Cosmodome|Cosmodome]] in Laval, Quebec, Canada.

==Illustrations==
===Elements of mechanical computing===
<gallery perrow=3 widths=180px>
Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Cone cam - Rocker arm - Rocket Arm Slider.jpg|fig.1
Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Rectifier.jpg|fig.2
Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Variable resistor - Diodes and resistors board.jpg|fig.3</gallery>
#[[:Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Cone cam - Rocker arm - Rocket Arm Slider.jpg|A combination of a conical cam, a rocker arm and a rocket arm worm screw conveyor transforms a rotary motion into an oscillation function, whose amplitude is varied by a manual setting]].
#[[:Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Rectifier.jpg|A combination which redresses an alternating motion into an analogous, unidirectional motion]].
#[[:Image: Voskhod spacecraft IMP 'Globus' navigation instrument. Variable resistor - Diodes and resistors board.jpg|A variable resistor rotating once every orbit returns the actual angular position within the orbit to other instruments]].

==See also==
*[[Globe|Terrestrial globe]]
*[[Astronomy:Voskhod 1|Voskhod 1]]
*[[Astronomy:Voskhod 2|Voskhod 2]]
*Voskhod rocket, the launcher used with the Voskhod spacecraft
*[[Astronomy:Voskhod programme|Voskhod programme]], including cancelled crewed missions
*Voskhod spacecraft, for which the Globus IMP 3 was specifically built
*Vostok spacecraft, instrumented with anterior versions of the IMP

==References==
{{Reflist|30em}}

==External links==
*[http://www.collectspace.com/ubb/Forum14/HTML/000733.html ''Researching and exhibiting Voskhod Globus''] on [http://www.collectspace.com www.collectSPACE.com - Space history and artifacts.]
*[http://www.cosmodome.org/index_en.html Cosmodome, Laval Qc (Canada)] {{Webarchive|url=https://web.archive.org/web/20111110181148/http://www.cosmodome.org/index_en.html |date=2011-11-10 }}
*[https://web.archive.org/web/20100126175844/http://www.nawcc.org/index.php/museumlibrary National Watch & Clock Museum, Columbia Pa (US)]
*[http://www.nasm.si.edu The Smithsonian Institution's National Air and Space Museum, Washington DC (US)]
*[http://vostoksupersite.weebly.com vostoksupersite.weebly.com - Vostok instrument panels, with details about IMP instruments]

{{DEFAULTSORT:Voskhod Spacecraft Globus IMP navigation instrument}}
[[Category:Navigational equipment]]
[[Category:Mechanical computers]]
[[Category:Voskhod program]]

{{Sourceattribution|Voskhod Spacecraft &quot;Globus&quot; IMP navigation instrument}}