On Apollo 17, the last manned mission to the Moon, the astronauts took with them a small buggy called the Lunar Rover. It was battery powered and could travel at just under 20k-min. (12mph), enabling astronauts to explore much more of the Moon than their predecessors had been able to do on foot. It had a small television camera and a satellite dish that sent the footage back to Earth. The Moon Buggy, as it is often called, had rubber tyres that could not be punctured, and was steered by a small hand control. It could be folded up and stored away when it was not needed.
The Apollo lunar roving vehicle was a battery-powered space buggy. The astronauts on Apollo 15, 16, and 17 used it to explore their landing sites and to travel greater distances than astronauts on earlier missions. The lunar rover neatly folded up inside the lunar lander during trips to the Moon. Once on the Moon’s surface, it unfolded with the help of springs. The lunar rover carried two astronauts and was manually driven. It was designed to climb steep slopes, to go over rocks, and to move easily over the Moon’s regolith. It was able to carry more than twice its own weight in passengers, scientific instruments, rocks, and regolith samples. The wheels on the rover were made of wire mesh (piano wire) with titanium cleats for treads. Engineers did not use solid or air-filled rubber tires because they would have been much heavier than were the wire mesh wheels. The Apollo spacecraft had a fixed amount of mass (payload) it could deliver to the surface, including the rover, rover batteries, scientific instruments, sample collection devices, etc. Hence, the wire-mesh wheels were important to the overall payload mass. This rover was not designed for prolonged use, and it is uncertain if future lunar explorers would use similar designs and materials for their vehicles, use new, more durable components, or turn to robotic rovers.
The LRV (Lunar Roving Vehicle) was technically a car, in that it had four wheels and two seats. Fenders over the wheels kept dust from flying everywhere, and the suspension incorporated double-swing A-arms, so overall it had a rather car-like look. Otherwise, it was radically different, starting with the exposed aluminum frame that was completely absent of bodywork. It also had no interior or even traditional controls like pedals and a steering wheel. A simple T-lever accessible by either astronaut was used to control turning, acceleration, and braking.
It did have four wheels, but instead of using solid rubber tires, a metallic mesh tire was developed using aluminum wires. Small titanium blocks arranged in a V-shape served as the tread, and it worked extremely well on the Moon’s very fine, powder-like surface.
They didn’t absorb impacts quite like air-filled tires, but astronauts remained secure in the LRV (Lunar Roving Vehicle) thanks to Velcro straps that kept them in the seats. To ensure the LRV (Lunar Roving Vehicle) could traverse the decidedly off-road environment on the Moon’s surface, four DC electric motors were installed in each wheel. That’s right – the LRV (Lunar Roving Vehicle) is a four-wheel-drive EV not unlike many modern electric hypercars, but it’s not nearly as powerful. Each motor produced the equivalent of just 0.25 horsepower. That power was transmitted to the wheels through a cycloidal gearbox with an 80:1 ratio, which allowed the rover to reach a top speed of approximately 8 mph (14 km/h).
Unlike modern EVs, the LRV was not rechargeable. Electricity was supplied via two zinc-silver batteries weighing a total of 119 pounds (54 kilograms). Total output was 8.7 kWh, and the LRV range was just 56 miles (90 kilometers). Another interesting tidbit about the individually-powered wheels is that all four could turn, giving the LRV a turning radius of just 9.8 feet (3 meters).
Picture Credit : Google