The Lunar Roving Vehicle (LRV) is a
battery-powered
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices.
When a battery is supplying power, its positive terminal is the cathode and its negat ...
four-wheeled
rover
Rover may refer to:
People
* Constance Rover (1910–2005), English historian
* Jolanda de Rover (born 1963), Dutch swimmer
* Rover Thomas (c. 1920–1998), Indigenous Australian artist
Places
* Rover, Arkansas, US
* Rover, Missouri, US
* ...
used on the
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
in the last three missions of the American
Apollo program (
15,
16, and
17) during 1971 and 1972. It is popularly called the Moon buggy, a play on the term ''
dune buggy''.
Built by Boeing, each LRV has a mass of without payload. It could carry a maximum payload of , including two astronauts, equipment, and lunar samples, and was designed for a top speed of , although it achieved a top speed of on its last mission,
Apollo 17
Apollo 17 (December 7–19, 1972) was the final mission of NASA's Apollo program, the most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on ...
.
Each LRV was carried to the Moon folded up in the
Lunar Module
The Apollo Lunar Module (LM ), originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed ...
's Quadrant 1 Bay. After being unpacked, each was driven an average of 30 km, without major incident. These three LRVs remain on the Moon.
History
The concept of a
lunar rover
A lunar rover or Moon rover is a space exploration vehicle designed to move across the surface of the Moon. The Apollo Program's Lunar Roving Vehicle was driven on the Moon by members of three American crews, Apollo 15, 16, and 17. Other rov ...
predated Apollo, with a 1952–1954 series in ''
Collier's Weekly
''Collier's'' was an American general interest magazine founded in 1888 by Peter Fenelon Collier. It was launched as ''Collier's Once a Week'', then renamed in 1895 as ''Collier's Weekly: An Illustrated Journal'', shortened in 1905 to ''Colli ...
'' magazine by
Wernher von Braun
Wernher Magnus Maximilian Freiherr von Braun ( , ; 23 March 191216 June 1977) was a German and American aerospace engineer and space architect. He was a member of the Nazi Party and Allgemeine SS, as well as the leading figure in the develop ...
and others, "
Man Will Conquer Space Soon!
"Man Will Conquer Space Soon!" was the title of a series of 1950s magazine articles in ''Collier's'' detailing Wernher von Braun's plans for manned spaceflight. Edited by Cornelius Ryan, the individual articles were authored by such space notables ...
" 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
Mieczysław Gregory Bekker (1905–1989) was a Polish engineer and scientist.
Bekker was born in Strzyżów, near Hrubieszów, Poland and graduated from Warsaw Technical University in 1929.
Early career
Bekker worked for the Polish Minist ...
published two books on land locomotion. At the time, Bekker was a
University of Michigan
, mottoeng = "Arts, Knowledge, Truth"
, former_names = Catholepistemiad, or University of Michigania (1817–1821)
, budget = $10.3 billion (2021)
, endowment = $17 billion (2021)As o ...
professor and a consultant to the
U.S. Army Tank-Automotive Command's Land Locomotion Laboratory. The books provided much of the theoretical basis for future lunar vehicle development.
Early lunar mobility studies
![Moon Buggy Ap16-KSC-71PC-777](https://upload.wikimedia.org/wikipedia/commons/0/0d/Moon_Buggy_Ap16-KSC-71PC-777.jpg)
In the February 1964 issue of ''
Popular Science
''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, incl ...
'', von Braun, then director of
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
's
Marshall Space Flight Center
The George C. Marshall Space Flight Center (MSFC), located in Redstone Arsenal, Alabama (Huntsville postal address), is the U.S. government's civilian rocketry and spacecraft propulsion research center. As the largest NASA center, MSFC's first ...
(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.
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
Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...
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.
Grumman and Northrop, in the fall of 1962, began to design pressurized-cabin vehicles, with electric motors for each wheel. At about this same time Bendix and Boeing started their own internal studies on lunar transportation systems.
Mieczysław Bekker, now with General Motors Defense Research Laboratories at
Santa Barbara, California
Santa Barbara ( es, Santa Bárbara, meaning "Saint Barbara") is a coastal city in Santa Barbara County, California, of which it is also the county seat. Situated on a south-facing section of coastline, the longest such section on the West Coas ...
, was completing a study for NASA's
Jet Propulsion Laboratory
The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States.
Founded in the 1930s by Caltech researchers, JPL is owned by NASA an ...
on a small, uncrewed lunar roving vehicle for the
Surveyor program
The Surveyor program was a NASA program that, from June 1966 through January 1968, sent seven robotic spacecraft to the surface of the Moon. Its primary goal was to demonstrate the feasibility of soft landings on the Moon. The Surveyor craft ...
.
Ferenc Pavlics, originally from
Hungary
Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia a ...
, used a wire-mesh design for "resilient wheels," a design that would be followed in future small rovers.
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 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 to Boeing, with GM's lab designated as the vehicle technology subcontractor. Bell Aerospace was already under contract for studies of Lunar Flying Vehicles.
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". 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. 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.
![Driving Distances on Mars and the Moon](https://upload.wikimedia.org/wikipedia/commons/e/e2/Driving_Distances_on_Mars_and_the_Moon.png)
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
lunar module
The Apollo Lunar Module (LM ), originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed ...
, 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
Huntsville is a city in Madison County, Limestone County, and Morgan County, Alabama, United States. It is the county seat of Madison County. Located in the Appalachian region of northern Alabama, Huntsville is the most populous city in t ...
, 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. 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' "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
roll bar gave protection from overturn 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 the 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
Weightlessness is the complete or near-complete absence of the sensation of weight. It is also termed zero gravity, zero G-force, or zero-G.
Weight is a measurement of the force on an object at rest in a relatively strong gravitational fi ...
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
The Waterways Experiment Station, also known as WES-Original Cantonment in Vicksburg, Mississippi, is a sprawling complex built in 1930 as a United States Army Corps of Engineers research facility. Its campus is the site of the headquarters of t ...
of the
U.S. Army Corps of Engineers
, colors =
, anniversaries = 16 June (Organization Day)
, battles =
, battles_label = Wars
, website =
, commander1 = ...
at
Vicksburg, Mississippi
Vicksburg is a historic city in Warren County, Mississippi, United States. It is the county seat, and the population at the 2010 census was 23,856.
Located on a high bluff on the east bank of the Mississippi River across from Louisiana, Vic ...
. 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
Yuma Proving Ground (YPG) is a United States Army series of environmentally specific test centers with its Yuma Test Center being one of the largest military installations in the world. It is subordinate to the U.S. Army Test and Evaluation ...
in
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
, as well as the Army's
Aberdeen Proving Ground
Aberdeen Proving Ground (APG) (sometimes erroneously called Aberdeen Proving ''Grounds'') is a U.S. Army facility located adjacent to Aberdeen, Harford County, Maryland, United States. More than 7,500 civilians and 5,000 military personnel work at ...
in
Maryland
Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...
.
Lunar Roving Vehicle Project
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.
Saverio "Sonny" Morea was named Lunar Roving Vehicle Project Manager.
On 11 July 1969, just before the successful Moon landing of
Apollo 11
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, an ...
, 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
Huntsville is a city in Madison County, Limestone County, and Morgan County, Alabama, United States. It is the county seat of Madison County. Located in the Appalachian region of northern Alabama, Huntsville is the most populous city in t ...
. 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
Santa Barbara ( es, Santa Bárbara, meaning "Saint Barbara") is a coastal city in Santa Barbara County, California, of which it is also the county seat. Situated on a south-facing section of coastline, the longest such section on the West Coas ...
, would furnish the mobility system (wheels, motors, and suspension); this effort would be led by GM Program Manager Samuel Romano and
Ferenc Pavlics. Boeing in
Seattle, Washington
Seattle ( ) is a port, seaport city on the West Coast of the United States. It is the county seat, seat of King County, Washington, King County, Washington (state), Washington. With a 2020 population of 737,015, it is the largest city in bo ...
, would furnish the electronics and navigation system. Vehicle testing would take place at the Boeing facility in
Kent, Washington
Kent is a city in King County, Washington, United States. It is part of the Seattle–Tacoma–Bellevue metropolitan area and had a population of 136,588 as of the 2020 census, making it the fourth-largest municipality in greater Seattle and t ...
, and the chassis manufacturing and overall assembly would be at the Boeing facility in Huntsville.
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
cancellation of further Apollo missions. Other LRV models were built: a static model to assist with
human factors
Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...
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. A paper by Saverio Morea gives details of the LRV system and its development.
[Morea, Saverio F.]
"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.
![Apollo15LunarRover2](https://upload.wikimedia.org/wikipedia/commons/e/e1/Apollo15LunarRover2.jpg)
LRVs were used for greater surface mobility during the Apollo
J-class missions,
Apollo 15
Apollo 15 (July 26August 7, 1971) was the ninth crewed mission in the United States' Apollo program and the fourth to Moon landing, land on the Moon. It was the first List of Apollo missions#Alphabetical mission types, J mission, with a ...
,
Apollo 16
Apollo 16 (April 1627, 1972) was the tenth crewed mission in the United States Apollo space program, administered by NASA, and the fifth and penultimate to land on the Moon. It was the second of Apollo's " J missions", with an extended sta ...
, and
Apollo 17
Apollo 17 (December 7–19, 1972) was the final mission of NASA's Apollo program, the most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on ...
. The rover was first used on 31 July 1971, during the Apollo 15 mission. 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.
["The Apollo Lunar Roving Vehicle"](_blank)
NASA Document. The rovers were designed with a top speed of about , although
Eugene Cernan
Eugene Andrew Cernan (; March 14, 1934 – January 16, 2017) was an American astronaut, naval aviator, electrical engineer, aeronautical engineer, and fighter pilot. During the Apollo 17 mission, Cernan became the eleventh human being to ...
recorded a maximum speed of , giving him the (unofficial) lunar land-speed record.
[Lyons, Pete; "10 Best Ahead-of-Their-Time Machines", ''Car and Driver'', Jan. 1988, p.78]
The LRV was developed in only 17 months and performed all its functions on the Moon with no major anomalies. Scientist-astronaut
Harrison Schmitt
Harrison Hagan Schmitt (born July 3, 1935) is an American geologist, retired NASA astronaut, university professor, former U.S. senator from New Mexico, and the most recent living person—and only person without a background in military aviation ...
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."
The LRVs experienced some minor problems. The rear
fender extension on the Apollo 16 LRV was lost during the mission's second
extra-vehicular activity
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA inc ...
(EVA) at station 8 when
John Young John Young may refer to:
Academics
* John Young (professor of Greek) (died 1820), Scottish professor of Greek at the University of Glasgow
* John C. Young (college president) (1803–1857), American educator, pastor, and president of Centre Coll ...
bumped into it while going to assist
Charles Duke
Charles Moss Duke Jr. (born October 3, 1935) is an American former astronaut, United States Air Force (USAF) officer and test pilot. As Lunar Module pilot of Apollo 16 in 1972, he became the tenth and youngest person to walk on the Moon, at ...
. 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
Eugene Andrew Cernan (; March 14, 1934 – January 16, 2017) was an American astronaut, naval aviator, electrical engineer, aeronautical engineer, and fighter pilot. During the Apollo 17 mission, Cernan became the eleventh human being to ...
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 National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States.
Established in 1946 as the National Air Museum, it opened its main building on the Nat ...
. The abrasion from the dust is evident on some portions of the makeshift fender.
![Moon Landing 1971 Issue-8c](https://upload.wikimedia.org/wikipedia/commons/0/0b/Moon_Landing_1971_Issue-8c.jpg)
The
color TV camera mounted on the front of the LRV could be remotely operated by
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
artificial objects on the Moon, as are the
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national ...
's uncrewed rovers, ''
Lunokhod 1
''Lunokhod 1'' ( Russian: Луноход-1 ("Moonwalker 1"), also known as Аппарат 8ЕЛ № 203 ("Device 8EL No. 203")) was the first of two robotic lunar rovers landed on the Moon by the Soviet Union as part of its Lunokhod program. The ...
'' and ''
Lunokhod 2
''Lunokhod 2'' (russian: Луноход-2 ("Moonwalker 2"), also known as Аппарат 8ЕЛ № 204 ("Device 8EL No. 204")) was the second of two unmanned lunar rovers that landed on the Moon by the Soviet Union as part of the Lunokhod progr ...
''.
Features and specifications
![NASA Apollo 17 Lunar Roving Vehicle](https://upload.wikimedia.org/wikipedia/commons/4/4d/NASA_Apollo_17_Lunar_Roving_Vehicle.jpg)
The Apollo Lunar Roving Vehicle is a
battery electric vehicle
A battery electric vehicle (BEV), pure electric vehicle, only-electric vehicle, fully electric vehicle or all-electric vehicle is a type of electric vehicle (EV) that exclusively uses chemical energy stored in rechargeable battery packs, wi ...
designed to operate in the low-gravity vacuum of the Moon and to be capable of traversing the lunar surface, allowing the Apollo astronauts to extend the range of their surface extravehicular activities. Three LRVs were used on the Moon: one on Apollo 15 by astronauts
David Scott
David Randolph Scott (born June 6, 1932) is an American retired test pilot and NASA astronaut who was the seventh person to walk on the Moon. Selected as part of the third group of astronauts in 1963, Scott flew to space three times and c ...
and
Jim Irwin, one on Apollo 16 by
John Young John Young may refer to:
Academics
* John Young (professor of Greek) (died 1820), Scottish professor of Greek at the University of Glasgow
* John C. Young (college president) (1803–1857), American educator, pastor, and president of Centre Coll ...
and
Charles Duke
Charles Moss Duke Jr. (born October 3, 1935) is an American former astronaut, United States Air Force (USAF) officer and test pilot. As Lunar Module pilot of Apollo 16 in 1972, he became the tenth and youngest person to walk on the Moon, at ...
, and one on Apollo 17 by
Eugene Cernan
Eugene Andrew Cernan (; March 14, 1934 – January 16, 2017) was an American astronaut, naval aviator, electrical engineer, aeronautical engineer, and fighter pilot. During the Apollo 17 mission, Cernan became the eleventh human being to ...
and
Harrison Schmitt
Harrison Hagan Schmitt (born July 3, 1935) is an American geologist, retired NASA astronaut, university professor, former U.S. senator from New Mexico, and the most recent living person—and only person without a background in military aviation ...
. The mission commander served as the driver, occupying the left-hand seat of each LRV. Features are available in papers by Morea,
Baker, and Kudish.
Mass and payload
The Lunar Roving Vehicles have a
mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...
of , and were designed to hold a
payload
Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...
of .
This resulted in weights in the approximately one-sixth
g on the lunar surface of empty (
curb weight
Vehicle weight is a measurement of wheeled motor vehicles; either an actual measured weight of the vehicle under defined conditions or a gross weight rating for its weight carrying capacity.
Curb or kerb weight
Curb weight (U.S. English) or kerb ...
) and fully loaded (
gross vehicle weight
Vehicle weight is a measurement of wheeled motor vehicles; either an actual measured weight of the vehicle under defined conditions or a gross weight rating for its weight carrying capacity.
Curb or kerb weight
Curb weight (U.S. English) or kerb ...
). The vehicle frame is long with a wheelbase of . The height of the vehicles is . The frame is made of
2219 aluminium alloy
2219 aluminium alloy is an alloy in the wrought aluminium-copper family (2000 or 2xxx series). It can be heat-treated to produce tempers with higher strength but lower ductility. The aluminium-copper alloys have high strength, but are generally les ...
tubing welded assemblies and consisted of a three-part chassis that was hinged in the center so it could be folded up and hung in the Lunar Module Quadrant 1 bay, which was kept open to space by omission of the outer skin panel. They have two side-by-side foldable seats made of tubular
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
with nylon webbing and aluminum floor panels. An armrest was mounted between the seats, and each seat had adjustable footrests and a
Velcro
Velcro, officially known as Velcro IP Holdings LLC and trading as Velcro Companies, is a British privately held company, founded by Swiss electrical engineer George de Mestral in the 1950s. It is the original manufacturer of hook-and-loop fasten ...
-fastened seat belt. A large mesh dish antenna was mounted on a mast on the front center of the rover. The suspension consists of a double horizontal wishbone with upper and lower
torsion bars and a damper unit between the chassis and upper wishbone. Fully loaded, the LRV has a ground clearance of .
Wheels and power
![Lunar Roving Vehicle wheel close-up](https://upload.wikimedia.org/wikipedia/commons/f/fa/Lunar_Roving_Vehicle_wheel_close-up.JPG)
The wheels were designed and manufactured by General Motors Defense Research Laboratories in
Santa Barbara, California
Santa Barbara ( es, Santa Bárbara, meaning "Saint Barbara") is a coastal city in Santa Barbara County, California, of which it is also the county seat. Situated on a south-facing section of coastline, the longest such section on the West Coas ...
.
Ferenc Pavlics was given special recognition by NASA for developing the "resilient wheel". They consisted of a
spun aluminum hub and a diameter, wide tire made of zinc-coated woven diameter steel strands attached to the rim.
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...
chevrons covered 50% of the contact area to provide traction. Inside the tire was a diameter titanium bump stop frame to protect the hub. Dust guards were mounted above the wheels. Each wheel had its own electric drive made by Delco, a
brushed DC electric motor A brushed DC electric motor is an internally commutated electric motor designed to be run from a direct current power source and utilizing an electric brush for contact.
Brushed motors were the first commercially important application of electri ...
capable of at 10,000 rpm, attached to the wheel via an 80:1
harmonic drive
Strain wave gearing (also known as harmonic gearing) is a type of mechanical gear system that uses a flexible spline with external teeth, which is deformed by a rotating elliptical plug to engage with the internal gear teeth of an outer spline. ...
, and a mechanical brake unit. In the case of drive failure, astronauts could remove pins to disengage the drive from the wheel, allowing the wheel to spin freely.
Maneuvering capability was provided through the use of front and rear steering motors. Each series-wound DC steering motor was capable of . The front and rear wheels could pivot in opposite directions to achieve a tight turning radius of , or could be decoupled so only front or rear would be used for steering. The wheels were linked in
Ackermann steering geometry
The Ackermann steering geometry is a geometric arrangement of linkages in the steering of a car or other vehicle designed to solve the problem of wheels on the inside and outside of a turn needing to trace out circles of different radii.
It was ...
, where the inside tires have a greater turn angle than the outside tires, to avoid sideslip.
Power was provided by two 36-volt
silver-zinc potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash.
Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...
non-rechargeable batteries developed by
Eagle-Picher
Eagle-Picher Technologies is a privately held, American, manufacturing company known for its battery technology, energetic devices and battery management systems. The company started in 1842 as the White Lead Company in Cincinnati, Ohio. A merge ...
with a charge capacity of 121
A·h
An ampere hour or amp hour (symbol: A⋅h or A h; often simplified as Ah) is a Unit of measurement, unit of electric charge, having Dimensional analysis, dimensions of electric current multiplied by time, equal to the charge transferred by a ...
each (a total of 242 A·h), yielding a range of . These were used to power the drive and steering motors and also a 36-volt utility outlet mounted on the front of the LRV to power the communications relay unit or the TV camera. LRV batteries and electronics were passively cooled, using change-of-phase wax
thermal capacitor packages and reflective, upward-facing radiating surfaces. While driving, radiators were covered with mylar blankets to minimize dust accumulation. When stopped, the astronauts would open the blankets, and manually remove excess dust from the cooling surfaces with hand brushes.
Control and navigation
![James Webb lunar drivers license](https://upload.wikimedia.org/wikipedia/commons/e/e2/James_Webb_lunar_drivers_license.jpg)
A T-shaped hand controller situated between the two seats controlled the four drive motors, two steering motors, and brakes. Moving the stick forward powered the LRV forward, left and right turned the vehicle left or right, and pulling backwards activated the brakes. Activating a switch on the handle before pulling back would put the LRV into reverse. Pulling the handle all the way back activated a parking brake. The control and display modules were situated in front of the handle and gave information on the speed, heading, pitch, and power and temperature levels.
Navigation was based on continuously recording direction and distance through use of a
directional gyro
The heading indicator (HI), also known as a directional gyro (DG) or direction indicator (DI), is a flight instrument used in an aircraft to inform the aviator, pilot of the aircraft's aircraft heading, heading.
Use
The primary means of estab ...
and
odometer
An odometer or odograph is an instrument used for measuring the distance traveled by a vehicle, such as a bicycle or car. The device may be electronic, mechanical, or a combination of the two (electromechanical). The noun derives from ancient Gr ...
and feeding this data to a computer that would keep track of the overall direction and distance back to the LM. There was also a Sun-shadow device that could give a manual heading based on the direction of the Sun, using the fact that the Sun moved very slowly in the sky.
Usage
The LRV was used during the lunar surface operations of Apollo 15, 16 and 17, the J missions of the Apollo program. On each mission, the LRV was used on three separate EVAs, for a total of nine lunar traverses, or sorties. During operation, the Commander (CDR) always drove, while the Lunar Module Pilot (LMP) was a passenger who assisted with navigation.
An operational constraint on the use of the LRV was that the astronauts must be able to walk back to the LM if the LRV were to fail at any time during the EVA (called the "Walkback Limit"). Thus, the traverses were limited in the distance they could go at the start and at any time later in the EVA. Therefore, they went to the farthest point away from the LM and worked their way back to it so that, as the life support consumables were depleted, their remaining walk back distance was equally diminished. This constraint was relaxed during the longest traverse on Apollo 17, based on the demonstrated reliability of the LRV and spacesuits on previous missions. A paper by Burkhalter and Sharp provides details on usage.
Deployment
Astronaut deployment of the LRV from the LM's open Quadrant 1 bay was achieved with a system of pulleys and braked reels using ropes and cloth tapes. The rover was folded and stored in the bay with the underside of the chassis facing out. One astronaut would climb the egress ladder on the LM and release the rover, which would then be slowly tilted out by the second astronaut on the ground through the use of reels and tapes. As the rover was let down from the bay, most of the deployment was automatic. The rear wheels folded out and locked in place. When they touched the ground, the front of the rover could be unfolded, the wheels deployed, and the entire frame let down to the surface by pulleys.
The rover components locked into place upon opening. Cabling, pins, and tripods would then be removed and the seats and footrests raised. After switching on all the electronics, the vehicle was ready to back away from the LM.
Locations
![Apollo 17 landing site, labeled](https://upload.wikimedia.org/wikipedia/commons/e/e3/Apollo_17_landing_site%2C_labeled.jpg)
Four flight-ready LRVs were manufactured, as well as several others for testing and training.
[ Three were transported to and left on the Moon via the ]Apollo
Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label=Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label= ...
15, 16, and 17 missions, with the fourth rover used for spare parts on the first three following the cancellation of Apollo 18. Since only the upper stages of the lunar excursion modules could return to lunar orbit from the surface, the vehicles, along with the lower stages were abandoned. As a result, the only lunar rovers on display are test vehicles, trainers, and mock-ups. The rover used on Apollo 15 was left at Hadley-Apennine (
). The rover used on Apollo 16 was left at Descartes (
). The rover used on Apollo 17 was left at Taurus-Littrow (
) and was seen by the Lunar Reconnaissance Orbiter
The Lunar Reconnaissance Orbiter (LRO) is a NASA robotic spacecraft currently orbiting the Moon in an eccentric polar mapping orbit. Data collected by LRO have been described as essential for planning NASA's future human and robotic missions t ...
during passes in 2009 and 2011. In 2020 the State of Washington designated the flown rovers as historic landmarks.
Several rovers were created for testing, training, or validation purposes. The engineering mockup is on display at the Museum of Flight
The Museum of Flight is a private non-profit air and space museum in the Seattle metropolitan area. It is located at the southern end of King County International Airport (Boeing Field) in the city of Tukwila, immediately south of Seattle.< ...
in Seattle, Washington
Seattle ( ) is a port, seaport city on the West Coast of the United States. It is the county seat, seat of King County, Washington, King County, Washington (state), Washington. With a 2020 population of 737,015, it is the largest city in bo ...
. The Qualification Test Unit is on display at the National Air and Space Museum
The National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States.
Established in 1946 as the National Air Museum, it opened its main building on the Nat ...
in Washington, D.C.
)
, image_skyline =
, image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...
The rover used for vibration testing is on display in the Davidson Saturn V Center at the U.S. Space & Rocket Center in Huntsville, Alabama
Huntsville is a city in Madison County, Limestone County, and Morgan County, Alabama, United States. It is the county seat of Madison County. Located in the Appalachian region of northern Alabama, Huntsville is the most populous city in t ...
. Additional test units are on display at the Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
in Houston, Texas
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in ...
, and the Kennedy Space Center Visitors Complex
The Kennedy Space Center Visitor Complex is the visitor center at NASA's Kennedy Space Center on Merritt Island, Florida. It features exhibits and displays, historic spacecraft and memorabilia, shows, two IMAX theaters, and a range of bus tour ...
in Cape Canaveral, Florida
Cape Canaveral ( es, Cabo Cañaveral, link=) is a city in Brevard County, Florida. The population was 9,912 at the 2010 United States Census. It is part of the Palm Bay–Melbourne– Titusville Metropolitan Statistical Area.
History
After t ...
. Replicas of rovers are on display at the National Museum of Naval Aviation
The National Naval Aviation Museum, formerly known as the National Museum of Naval Aviation and the Naval Aviation Museum, is a military and aerospace museum located at Naval Air Station Pensacola, Florida.
Founded in 1962 and moved to its curr ...
in Pensacola, Florida
Pensacola () is the westernmost city in the Florida Panhandle, and the county seat and only incorporated city of Escambia County, Florida, United States. As of the 2020 United States census, the population was 54,312. Pensacola is the principal ...
, the Evergreen Aviation & Space Museum
The Evergreen Aviation & Space Museum is an aviation museum in McMinnville, Oregon. Its exhibits include the Hughes H-4 Hercules (''Spruce Goose'') and more than fifty military and civilian aircraft, unmanned aerial vehicles (drones), and spac ...
in McMinnville, Oregon
McMinnville is the county seat of and largest city in Yamhill County, Oregon, United States. The city is named after McMinnville, Tennessee. As of the 2019 census, the city had a population estimate of 34,743.
McMinnville is at the confluence of ...
, the Kansas Cosmosphere and Space Center
Cosmosphere is a space museum and STEM education center in Hutchinson, Kansas, United States. It was previously known as the Kansas Cosmosphere. The museum houses over 13,000 spaceflight artifacts—the largest combined collection of US and R ...
in Hutchinson, Kansas
Hutchinson is the largest city and county seat in Reno County, Kansas, United States, and located on the Arkansas River. It has been home to salt mines since 1887, thus its nickname of "Salt City", but locals call it "Hutch". As of the 2020 cen ...
and the Omega Museum in Biel, Switzerland
Biel/Bienne (official bilingual wording; , ) is a List of towns in Switzerland, town and a Municipalities of Switzerland, municipality in the Biel/Bienne (administrative district), Biel/Bienne administrative district in the canton of Bern in Swi ...
. A replica on loan from the Smithsonian Institution is on display at the Mission: Space attraction at Epcot
Epcot, stylized in all uppercase as EPCOT, is a theme park at the Walt Disney World Resort in Bay Lake, Florida. It is owned and operated by The Walt Disney Company through its Parks, Experiences and Products division. Inspired by an unreal ...
at the Walt Disney World Resort
The Walt Disney World Resort, also called Walt Disney World or Disney World, is an entertainment resort complex in Bay Lake, Florida, Bay Lake and Lake Buena Vista, Florida, Lake Buena Vista, Florida, United States, near the cities of Orlando ...
near Orlando, Florida
Orlando () is a city in the U.S. state of Florida and is the county seat of Orange County, Florida, Orange County. In Central Florida, it is the center of the Greater Orlando, Orlando metropolitan area, which had a population of 2,509,831, acco ...
.
Media
Image:Ap16 rover.ogv, Apollo 16
Apollo 16 (April 1627, 1972) was the tenth crewed mission in the United States Apollo space program, administered by NASA, and the fifth and penultimate to land on the Moon. It was the second of Apollo's " J missions", with an extended sta ...
Commander John Young drives Lunar Rover 002
Image:Apollo 15 Lunar Rover training.ogg, Dave Scott and Jim Irwin train on Earth to use the Lunar Rover on Apollo 15
Apollo 15 (July 26August 7, 1971) was the ninth crewed mission in the United States' Apollo program and the fourth to Moon landing, land on the Moon. It was the first List of Apollo missions#Alphabetical mission types, J mission, with a ...
See also
* List of artificial objects on the Moon
This is a partial list of artificial materials left on the Moon, many during the missions of the Apollo program. The table below does not include lesser Apollo mission artificial objects, such as a hammer and other tools, retroreflectors, Apollo ...
* Lunar Terrain Vehicle
The Lunar Terrain Vehicle (LTV) is an unpressurized rover being developed by NASA that astronauts can drive on the Moon while wearing their spacesuits. The development of the LTV is a part of NASA's Artemis Program which involves returning astrona ...
* Modular Equipment Transporter
The Modular Equipment Transporter (MET) was a two-wheeled, hand-pulled vehicle that was used as an equipment hauling device on traverses across the lunar surface. Designed after Apollo 12 astronauts Pete Conrad and Alan Bean had difficulties lugg ...
References
External links
Boeing Lunar Rover Vehicle Operations Handbook
Article about the rover
LRV Operations Handbook, Appendix A (Performance Data)
Mobility Performance of the Lunar Roving Vehicle: Terrestrial Studies – Apollo 15 Results
Video
Lunar and Planetary Rovers: The Wheels of Apollo and the Quest for Mars
– Apollo Lunar Surface Journal
Lunar Roving Vehicle at the Smithsonian National Air and Space Museum
Lunar Roving Vehicle Collection, The University of Alabama in Huntsville Archives and Special Collections
Ronald Lancaster Collection, The University of Alabama in Huntsville Archives and Special Collections
Engineer's collection of photos and documents on the design and construction of the LRV.
{{DEFAULTSORT:Lunar Rover (Apollo)
Exploration of the Moon
Apollo program hardware
Missions to the Moon
Lunar rovers
Electric cars
All-wheel-drive vehicles
NASA vehicles
Articles containing video clips
Apollo 15
Apollo 16
Apollo 17
Off-road vehicles
1971 on the Moon
1972 on the Moon