Editing Lunar Roving Vehicle (section)

==History==

The concept of a [[lunar rover]] predated Apollo, with a 1952–1954 series in ''[[Collier's Weekly]]'' magazine by [[Wernher von Braun]] and others, "[[Man Will Conquer Space Soon!]]" In this, von Braun described a six-week stay on the Moon, featuring 10-ton tractor-trailers for moving supplies.

In 1956, [[Mieczysław G. Bekker]] published two books on land locomotion<ref>Bekker, Mieczyslaw G.; ''Theory of Land Locomotion'', U. Michigan Press, 1956, and ''The Mechanics of Vehicle Mobility'', U. Michigan Press, 1956 and 1962</ref> while he was a [[University of Michigan]] professor and a consultant to the [[United States Army TACOM Life Cycle Management Command|U.S. Army Tank-Automotive Command]]'s Land Locomotion Laboratory. The books provided much of the theoretical basis for future lunar vehicle development.

In 1959, [[Georg von Tiesenhausen]] conceived the lunar rover<ref>{{cite web |url=https://www.nasa.gov/wp-content/uploads/2016/08/19881129_georg_von_tiesenhausen.pdf |title=Georg von Tiesenhausen Oral History Interview |date=1988-11-29 |website=nasa.gov |access-date=2024-02-20}}</ref><ref>{{cite web |url=https://www.al.com/news/huntsville/2015/05/german_rocket_team_member_101.html |title=Georg von Tiesenhausen, 101 on Monday, owns spot as the last German rocket team member |last=Roop |first=Lee |date=2015-05-15 |website=AL.com |access-date=2024-02-20}}</ref> as a [[Individual wheel drive|four-wheel-drive]] vehicle with [[Airless tire|noninflated]], flexible wheels.<ref name=":0">{{cite web |url=https://www.nasa.gov/wp-content/uploads/static/history/alsj/lrv_historical_origins.pdf |title=Lunar Roving Vehicle: Historical Origins, Development, and Deployment |last1=Burkhalter |first1=Bettye B. |last2=Sharpe |first2=Mitchell R. |date=1995 |website=nasa.gov |publisher=[[Journal of the British Interplanetary Society]] |access-date=2024-02-20}}</ref>

=== Early lunar mobility studies ===
In the February 1964 issue of ''[[Popular Science]]'', von Braun, then director of [[NASA]]'s [[Marshall Space Flight Center]] (MSFC), discussed the need for a lunar surface vehicle, and revealed that studies had been underway at Marshall in conjunction with Lockheed, Bendix, Boeing, General Motors, Brown Engineering, Grumman, and Bell Aerospace.<ref>von Braun, Wernher; [https://books.google.com/books?id=qS0DAAAAMBAJ&pg=PA18 "How We'll Travel on the Moon,"] ''Popular Science'', February 1964, pp. 18–26</ref> [[Saverio "Sonny" Morea|Saverio Morea]] was named LRV Manager at MSFC in 1961.<ref name=":0" />
[[File:Lander Rover Apollo Mission.jpg|thumb|MOLAB, NASA Illustration, 1960]]
Beginning in the early 1960s, a series of studies centering on lunar mobility were conducted under Marshall. This began with the lunar logistics system (LLS), followed by the mobility laboratory (MOLAB), then the lunar scientific survey module (LSSM), and finally the mobility test article (MTA). In early planning for the [[Apollo program]], it had been assumed that two [[Saturn V]] launch vehicles would be used for each lunar mission: one for sending the crew aboard a Lunar Surface Module (LSM) to lunar orbit, landing, and returning, and a second for sending an LSM-Truck (LSM-T) with all of the equipment, supplies, and transport vehicle for use by the crew while on the surface. All of the first Marshall studies were based on this dual-launch assumption, allowing a large, heavy, roving vehicle. <ref>Young, Anthony; ''Lunar and planetary rovers: the wheels of Apollo and the quest for Mars''; Springer, 2007, pp. 30–57; {{ISBN|0-387-30774-5}}</ref>

Grumman and Northrop, in late 1962, began to design pressurized-cabin vehicles, with electric motors for each wheel. At about this same time, Bendix and Boeing started their internal studies on lunar transportation systems. [[Mieczysław G. Bekker|Mieczysław Bekker]], now with General Motors Defense Research Laboratories at [[Santa Barbara, California]], was completing a study for NASA's [[Jet Propulsion Laboratory]] on a small, uncrewed lunar roving vehicle for the [[Surveyor program]]. [[Ferenc Pavlics]], originally from [[Hungary]], used a wire-mesh design for "resilient wheels," a design that would be followed in future small rovers.<ref>Bekker, Mieczyslaw G., and Ferenc Pavlics; "Lunar Roving Vehicle Concept: A Case Study"; GMDRL Staff Paper SP63-205, May 1963</ref>

In early 1963, NASA selected Marshall for studies in an Apollo Logistics Support System (ALSS). Following reviews of all earlier efforts, this resulted in a 10-volume report. Included was the need for a pressurized vehicle in the {{convert|6490|-|8470|lb|kg|abbr=on}} weight range, accommodating two men with their expendables and instruments for traverses up to two weeks in duration. In June 1964, Marshall awarded contracts to Bendix and Boeing, with GM's lab designated as the vehicle technology subcontractor.<ref>[http://www.astronautix.com/craft/molab.htm "Molab,"] {{webarchive|url=https://web.archive.org/web/20111012091139/http://astronautix.com/craft/molab.htm|date=12 October 2011}} ''Encyclopedia Astronautics''</ref> Bell Aerospace was already under contract for studies of Lunar Flying Vehicles.<ref>Courter, Robert; [https://books.google.com/books?id=NyoDAAAAMBAJ&pg=PA55 "What It's Like to Fly the Jet Belt,"] ''Popular Science'', Nov. 1969, pp. 55–59, 190</ref>

Even as the Bendix and Boeing studies were underway, Marshall was examining a less ambitious surface exploration activity, the LSSM. This would be composed of a fixed, habitable shelter–laboratory with a small lunar-traversing vehicle that could either carry one man or be remotely controlled. This mission would still require a dual launch with the moon vehicle carried on the "lunar truck".<ref>{{Cite book |url=https://history.nasa.gov/alsj/LM23_LM_Derivatives_LMD1-13.pdf |title=APOLLO NEWS REFERENCE - LUNAR MODULE DERIVATIVES FOR FUTURE SPACE MISSIONS |publisher=Grumman}}</ref> Marshall's Propulsion and Vehicle Engineering (P&VE) lab contracted with Hayes International to make a preliminary study of the shelter and its related vehicle.<ref>[https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19650014414_1965014414.pdf "Lunar Shelter/Rover Conceptual Design and Evaluation,"] NASA CR-61049, Nov. 1964.</ref>  Because of the potential need for an enclosed vehicle for enlarged future lunar explorations, those design efforts continued for some time and resulted in several full-scale test vehicles.

[[File:Driving Distances on Mars and the Moon.png|thumb|left|Comparison of distances driven by various wheeled vehicles on the surface of the [[Moon]] and [[Mars]]]]

With pressure from Congress to hold down Apollo costs, Saturn V production was reduced, allowing only a single launch per mission. Any roving vehicle would have to fit on the same lunar module as the astronauts. In November 1964, two-rocket models were put on indefinite hold, but Bendix and Boeing were given study contracts for small rovers. The name of the lunar excursion module was changed to simply the [[Apollo Lunar Module|lunar module]], indicating that the capability for powered "excursions" away from a lunar-lander base did not yet exist. There could be no mobile lab—the astronauts would work out of the LM. Marshall also continued to examine uncrewed robotic rovers that could be controlled from the Earth.

From the beginnings at Marshall, the Brown Engineering Company of [[Huntsville, Alabama]], had participated in all of the lunar mobility efforts. In 1965, Brown became the prime support contractor for Marshall's P&VE Laboratory. With an urgent need to determine the feasibility of a two-man self-contained lander, von Braun bypassed the usual procurement process and had P&VE's Advanced Studies Office directly task Brown to design, build, and test a prototype vehicle.<ref>"Brown Builds Concept Of Lunar Vehicle," ''BECO Views'', Vol. 9, Jan. 1966, p. 1</ref> While Bendix and Boeing would continue to refine concepts and designs for a lander, test model rovers were vital for Marshall human factors studies involving spacesuit-clad astronauts interfacing with power, telemetry, navigation, and life-support rover equipment.

Brown's team made full use of the earlier small-rover studies, and commercially available components were incorporated wherever possible. The selection of wheels was of great importance, and almost nothing was known at that time about the lunar surface. The Marshall Space Sciences Laboratory (SSL) was responsible for predicting surface properties, and Brown was also prime support contractor for this lab; Brown set up a test area to examine a wide variety of wheel-surface conditions. To simulate Pavlics's "resilient wheel," a four-foot-diameter inner tube wrapped with nylon ski rope was used. On the small test rover, each wheel had a small electric motor, with overall power provided by standard truck batteries. A [[Rollover protection structure|roll bar]] gave protection from overturning accidents.

In early 1966, Brown's vehicle became available for examining human factors and other testing. Marshall built a small test track with craters and rock debris where several different mock-ups were compared; it became obvious that a small rover would be best for the proposed missions. The test vehicle was also operated in remote mode to determine characteristics that might be dangerous to the driver, such as acceleration, bounce-height, and turn-over tendency as it traveled at higher speeds and over simulated obstacles. The test rover's performance under one-sixth gravity was obtained through flights on a KC-135A aircraft in a [[Reduced gravity aircraft|Reduced Gravity]] [[parabolic trajectory|parabolic]] maneuver; among other things, the need for a very soft wheel and suspension combination was shown. Although Pavlics' wire-mesh wheels were not initially available for the reduced gravity tests, the mesh wheels were tested on various soils at the [[Waterways Experiment Station]] of the [[United States Army Corps of Engineers|U.S. Army Corps of Engineers]] at [[Vicksburg, Mississippi]]. Later, when wire-mesh wheels were tested on low-g flights, the need for wheel fenders to reduce dust contamination was found. The model was also extensively tested at the U.S. Army's [[Yuma Proving Ground]] in [[Arizona]], as well as the Army's [[Aberdeen Proving Ground]] in [[Maryland]].

=== Lunar Roving Vehicle Project ===
[[File:Moon Buggy Ap16-KSC-71PC-777.jpg|thumb|[[Apollo 16]] astronauts in the 1-g trainer]]

During 1965 and 1967, the Summer Conference on Lunar Exploration and Science brought together leading scientists to assess NASA's planning for exploring the Moon and to make recommendations. One of their findings was that the LSSM was critical to a successful program and should be given major attention. At Marshall, von Braun established a Lunar Roving Task Team, and in May 1969, NASA approved the Manned Lunar Rover Vehicle Program as a Marshall hardware development. The project was led by [[Eberhard Rees]], Director of Research and Development at Marshall, who oversaw the design and construction of the rover,<ref>{{cite web |url=https://www.nae.edu/28690/Dr-Eberhard-F-M-Rees |title=Dr. Eberhard F. M. Rees |website=nae.edu |publisher=[[National Academy of Engineering]] |access-date=2024-02-20}}</ref><ref>{{cite web |url=https://www.nasa.gov/people/eberhard-rees/ |title=Eberhard Rees |website=nasa.gov |access-date=2024-02-20}}</ref> with [[Saverio "Sonny" Morea|Saverio Morea]] acting as project manager.<ref name=":0" />

On 11 July 1969, just before the successful Moon landing of [[Apollo 11]], a [[request for proposal]] for the final development and building the Apollo LRV was released by Marshall. Boeing, Bendix, Grumman, and Chrysler submitted proposals. Following three months of proposal evaluation and negotiations, Boeing was selected as the Apollo LRV prime contractor on 28 October 1969. Boeing would manage the LRV project under Henry Kudish in [[Huntsville, Alabama]]. Kudish was replaced the following year in 1970 by LRV Project Manager Earl Houtz. As a major subcontractor, the General Motors Defense Research Laboratories in [[Santa Barbara, California]], would furnish the mobility system (wheels, motors, and suspension); this effort would be led by GM Program Manager Samuel Romano and<ref>From the Moon to the Balloon, New Jersey's Amazing Aviation History, HV Pat Reilly, 1992</ref> [[Ferenc Pavlics]].<ref>{{cite web|url=http://old.pulispace.com/en/education/space-moon-and-the-hungarians/100-interview-with-ferenc-pavlics-lead-developer-of-the-apollo-lunar-rovers|title=Interview with Ferenc Pavlics, lead developer of the Apollo Lunar Rovers|first=Ádám|last=Csillag|website=www.pulispace.com}}</ref> Boeing in [[Seattle, Washington]], would furnish the electronics and navigation system. Vehicle testing would take place at the Boeing facility in [[Kent, Washington]], and the chassis manufacturing and overall assembly would be completed at the Boeing facility in Huntsville.<ref>"Lunar Roving Vehicle," MSFC press release, 29 October 1969; ''Marshall Star'', 3 November 1969</ref>

[[File:Apollo15LunarRover2.jpg|thumb|upright=1.3|[[Apollo 15]] – Commander [[David Scott (astronaut)|David Scott]] drives the Rover near the LM ''Falcon'']]

The first cost-plus-incentive-fee contract to Boeing was for $19,000,000 and called for delivery of the first LRV by 1 April 1971. Cost overruns, however, led to a final cost of $38,000,000, which was about the same as NASA's original estimate. Four lunar rovers were built, one each for Apollo missions 15, 16, and 17; and one used for spare parts after the [[Canceled Apollo missions|cancellation of further Apollo missions]]. Other LRV models were built: a static model to assist with [[human factors]] design; an engineering model to design and integrate the subsystems; two one-sixth gravity models for testing the deployment mechanism; a one-gravity trainer to give the astronauts instruction in the operation of the rover and allow them to practice driving it; a mass model to test the effect of the rover on the LM structure, balance, and handling; a vibration test unit to study the LRV's durability and handling of launch stresses; and a qualification test unit to study integration of all LRV subsystems.<ref name="ApolloVehiclesNASA">{{cite web |date=15 November 2005 <!-- "last updated" date at the bottom of the page --> |title=The Apollo Lunar Roving Vehicle |url=http://nssdc.gsfc.nasa.gov/planetary/lunar/apollo_lrv.html |access-date=16 May 2010 |publisher=[[NASA]]}}</ref> A paper by Saverio Morea gives details of the LRV system and its development.<ref name="Morea1988">Morea, Saverio F.; [https://web.archive.org/web/20100527104907/http://history.msfc.nasa.gov/lunar/LRV_Historical_Perspective.pdf "The Lunar Roving Vehicle – Historical Perspective"];  Proc. 2nd Conference on Lunar Bases and Space Activities, 5–7 April 1988; NASA Conference Publications 3166, Vol. 1, pp. 619–632.</ref>[[Image:Apollo 16 LM Orion.jpg|thumb|upright=1.3|[[John Young (astronaut)|John Young]] works at the LRV near the [[Apollo Lunar Module|LM]] ''Orion'' on [[Apollo 16]] in April 1972.]]LRVs were used for greater surface mobility during the Apollo [[List of Apollo missions#Alphabetical mission types|J-class]] missions, [[Apollo 15]], [[Apollo 16]], and [[Apollo 17]]. The rover was first used on 31 July 1971, during the Apollo 15 mission.<ref>{{cite news |url=https://www.nytimes.com/2021/07/27/science/lunar-rover-apollo-nasa.html |title=50 Years Ago, NASA Put a Car on the Moon |first=Rebecca |last=Boyle |date=July 27, 2021 |work=[[The New York Times]] |access-date=July 30, 2021}}</ref> This greatly expanded the range of the lunar explorers. Previous teams of astronauts were restricted to short walking distances around the landing site due to the bulky space suit equipment required to sustain life in the lunar environment. The range, however, was operationally restricted to remain within walking distance of the lunar module, in case the rover broke down at any point.<ref name="TALRV_NASA">[http://nssdc.gsfc.nasa.gov/planetary/lunar/apollo_lrv.html "The Apollo Lunar Roving Vehicle"], NASA Document.</ref> The rovers were designed with a top speed of about {{convert|8|mph|km/h|abbr=on|0}}, although [[Eugene Cernan]] recorded a maximum speed of {{convert|11.2|mph|km/h|abbr=on}}, giving him the (unofficial) lunar land-speed record.<ref name="Lyons1988">Lyons, Pete; "10 Best Ahead-of-Their-Time Machines", ''Car and Driver'', Jan. 1988, p.78</ref>

The LRV was developed in only 17 months and performed all its functions on the Moon with no major anomalies. Scientist-astronaut [[Harrison Schmitt]] of Apollo 17 said, "The Lunar Rover proved to be the reliable, safe and flexible lunar exploration vehicle we expected it to be. Without it, the major scientific discoveries of Apollo 15, 16, and 17 would not have been possible; and our current understanding of lunar evolution would not have been possible."<ref name="TALRV_NASA"/>

The LRVs experienced some minor problems. The rear [[Fender (vehicle)|fender]] extension on the Apollo 16 LRV was lost during the mission's second [[extra-vehicular activity]] (EVA) at station 8 when [[John Young (astronaut)|John Young]] bumped into it while going to assist [[Charles Duke]]. The dust thrown up from the wheel covered the crew, the console, and the communications equipment. High battery temperatures and resulting high power consumption ensued. No repair attempt was mentioned.

The fender extension on the Apollo 17 LRV broke when accidentally bumped by [[Eugene Cernan]] with a hammer handle. Cernan and Schmitt taped the extension back in place, but due to the dusty surfaces, the tape did not adhere, and the extension was lost after about one hour of driving, causing the astronauts to be covered with dust. For their second EVA, a replacement "fender" was made with some EVA maps, duct tape, and a pair of clamps from inside the Lunar Module that were nominally intended for the moveable overhead light. This repair was later undone so that the clamps could be taken inside for the return launch. The maps were brought back to Earth and are now on display at the [[National Air and Space Museum]]. The abrasion from the dust is evident on some portions of the makeshift fender.<ref>[https://www.hq.nasa.gov/alsj/RP-1994-1317.pdf NASA Reference Publication 1317, Jan 1994, Sullivan, Thomas A. "Catalog of Apollo Experiment Operations" pg. 68 "Experimental Operations During Apollo EVAs: Repairs to Experiments,"] NASA Document.</ref><ref>[https://science.nasa.gov/science-news/science-at-nasa/2008/21apr_ducttape/ "Moondust and Duct Tape,"] NASA Document.</ref>
[[File:Moon Landing 1971 Issue-8c.jpg|thumb|upright=1.32|right|{{center|The Lunar Rover Vehicle depicted on the [[U.S. Space Exploration History on U.S. Stamps|Space Achievement]] Decade Issue of 1971}}]]

The [[Apollo TV camera|color TV camera]] mounted on the front of the LRV could be remotely operated by [[Mission Control Center|Mission Control]] in pan and tilt axes as well as zoom. This allowed far better television coverage of the EVA than the earlier missions. On each mission, at the conclusion of the astronauts' stay on the surface, the commander drove the LRV to a position away from the Lunar Module so that the camera could record the ascent stage launch. The camera operator in Mission Control experienced difficulty in timing the various delays so that the LM ascent stage was in frame through the launch. On the third and final attempt (Apollo 17), the launch and ascent were successfully tracked.

NASA's rovers, left behind, are among the [[List of man-made objects on the Moon|artificial objects on the Moon]], as are the [[Soviet Union]]'s uncrewed rovers, ''[[Lunokhod 1]]'' and ''[[Lunokhod 2]]''.