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Lunar Roving Vehicle
Lunar rover Apollo 17

The Lunar Roving Vehicle or LRV is a small dune-buggy car that permitted the Apollo astronauts to drive from the vicinity of their landing site on the moon to make geological observations, collect rock/soil samples and use scientific instruments at various moon locations. The Lunar Rover was first used during Apollo 15 which launched on July 26, 1971. This was the fourth lunar landing that permitted human exploration on the Moon's surface. The LRV was also used during Apollo missions 16 and 17.

The LRV weighed about 480 earth pounds (80 pounds on the moon). It could carry two astronauts along with their portable life support systems and scientific instruments. The LRV could carry about twice its own weight so there was plenty of room for the lunar material samples the astronauts collected. The LRV was designed for low speed and high torque. It was limited to 8 mph (3.5 meters per second) for safety reasons. Going over rough lunar surfaces could have been a danger to the crew. It could climb a 25 degree slope so it could more easily travel over the uneven surface.

The wheels on the rover were made of wire mesh (piano wire) with titanium cleats for treads. The engineers did not use solid or air-filled rubber tires because they would have been much heavier. The Apollo spacecraft could only carry a fixed amount of weight (mass) so the wire-mesh wheels were important for keeping the weight of the vehicle low.

One of the instruments which was carried on the Lunar Rover was a Traverse Gravimeter. It was used to measure and map the gravitational fields on the Moon.


LRV Statistics

Size Weight Ground Clearance Power Wheels Steering System Navigation System Speedometer

10 feet long

(3 meters)

480 Earth pounds

(216 kilograms)

13 inches on level ground

(33 centimenters)

2 Electric battery systems

4 - 32 inch wheels

(81.3 centimeters)

Control stick mounted in vehicle center Computes distance and direction to lunar module Display shows speed in kilometers per hour
6 feet wide (1.8 meters)

80 moon pounds

(36 kilograms)

  Electric motor in each wheel. Both front and rear wheels steer Either astronaut could steer. Display shows heading of vehicle,bearing in degrees,kilometers from module Speed up to 8 mph (3.5 meters per second)

7.5 feet wheelbase

(2.3 meters)

    If wheel motor fails it can be decoupled - others take over to drive LRV.   Rear or front steering mechanism can provide full service if one fails. System uses angle of sun and declination of module to set gyroscope before leaving in LRV.  
      Designed for 78 hour life-time     Uses assumed lunar north to set bearing.  

TV - Communications Systems

A color TV camera and communication system that permitted the astronauts to transmit pictures and voice communications directly from the vehicle to Earth were carried on board the LRV. Still-picture cameras were mounted on the chest of each astronaut for additional pictures. The TV camera could be controlled remotely from Mission Control Center in Houston.

Traveling to the Moon

The LRV was folded up and placed inside the lunar module. The chassis (body) of the LRV is hinged in three places so it was folded in thirds and the 4 wheels were pivoted or turned nearly flat against the folded chassis. It occupied only 30 cubic feet. It was stowed inside the descent stage of the lunar module in quadrant Number 1 to the right of the ladder down which the astronauts descended to the Moon's surface.

descent diagram

Lunar Module Descent Stage Diagram
Click diagram for a larger view

The Descent Stage held the lunar rover during the flight to the Moon.

The Lunar Module traveled to the moon inside this Lunar Module Adapter.

Click here for a larger view or to print out a larger diagram.

 

Getting Operational

Once on the lunar surface the LRV could be removed from the lunar module. The first astronaut would descend the ladder and remove a contingency cable from quadrant Number 1. The second astronaut would then pull a D-ring mounted on the side of the lunar module. By pulling this, the LRV would be released at the top. The first astronaut would then pull a series of cables which would lower the LRV from the lunar module and unfold it as it moves to the Moon's surface. Once on the surface with the four wheels deployed, the astronauts would mount the camera, and load equipment and scientific gear to prepare for the lunar trip.

Apollo 15 rover

Astronauts drove within a radius of the lunar module from which they could walk back should the LRV break down. Even so, some 50 square miles of exploration was possible.

The LRV was designed to have a 78 hour life-time during the lunar day where the temperature in the sun was 243 degrees F and shadows where the temperature plunged to -279 degrees F.

 

rover model LRV

For more information see the NASA Lunar Rover site.