We know that the Soviets sent the first satellite, the first animal and the first human into space. The robotics component of their conquest of space is much less well-known, but no less impressive. In the 1960s, while the USA devoted their energies to landing a man on the Moon, the Soviets based their mission on Lunakhod. These mobile robots, remote-controlled from Earth between 1970 and 1973, travelled dozens of kilometres and collected valuable images and scientific data on our natural satellite.
Sending a robot to another world and controlling it was not successfully repeated until 1996 by the Mars Pathfinder team. Though spectacular, especially considering the era, the Lunakhod program’s achievements are little known because it remained top secret for many years.
Here is an amazing documentary on this cold war background story (parts1, 2, 3 and 4). It ends with the engineering team’s ultimate exploit: adapting their lunar robot design in three months to create a remote-controlled robot to help clean nuclear Reactor 3's roof after the Chernobyl disaster.