A few interesting videos about the lunokhod rovers:
The chief designer of the lunokhods (Lunokhod 1 & 2) was Aleksandr Kemurdzhian, a tank designer. Being a tank designer his initial designs had the lunokhod use tracks, but research indicated tracks could get stuck in certain situations so the design was changed to eight independently moving wheels. According to Secret Soviet Lunar Rovers and Extra Terrestrial Cars - Lunokhod, the vehicles could move if only three wheels weren't stuck. The development of the lunokhods was very well tested and researched prior to construction and deployment.
To power the craft during the lunar day solar cells on the inside of a lid for the craft were used. During the lunar night, the lid was closed, the internal compartment of the lunokhods was filled with a gas heated by an external polonium-210 source.
The lunokhods had four corner cameras produced high-resolution panoramic images, with a pair of front-mounted TV cameras for the rover’s operators.
Each lunokhod was controlled by a five man team, a driver, commander, navigator, engineer and radio operator – having practiced on a simulated lunar surface.
The sweating driver was guided not by video but a succession of still images, updated every 20 seconds. He had to contend with the 2.5-second signal delay, as well as a metre-wide blind spot ahead. Lunokhod 1 had two speeds: 0.8 km/h or 2km/h, plus reverse gear. Drivers recalled details from previous images to manoeuvre safely and were dependent on shadows to make out surface relief. They did not drive during the three days of lunar noon, or when the Sun was low in the sky. Each lunar night they left the rover to hibernate.
From ROBOTIC AND MANNED LUNAR ROVERS OF THE XX CENTURY: THE VIEW FROM THE XXI CENTURY
The accumulated experience of the crew resulted in an increased duration of typical non-stop driving time from
50 s for Lunokhod-1 to 350 s for Lunokhod-2.
The remote control drivers were located at Simferopol in Crimea.
The design of the lunokhods was robust enough for even longer missions but the demise of Lunokhod 1 was the exhaustion of polonium-210. Lunokhod 2 failed due to overheating after it was accidentally driven into a crater the drivers didn't notice. Lunokhod 2 was simply driven through the crater which, unknowingly, had soft walls which covered part of Lunokhod 2 with dust. When then lid was open the dust was deposited on thermal exchange unit and Lunokhod 2 stopped functioning shortly afterwards.
As a side note, Aleksandr Kemurdzhian designed rovers for the clean up of Chernobyl, after the ones obtained from the then East Germany failed to operate as anticipated.
