Meet the Vertidrive sandblasting robot from BlastOne: a machine that can climb and blast vertical surfaces such as water tanks, ship hulls, and other large steel structures. It has magnets on each of its wheels and a continuously oscillating arm that can carry up to 3 blast nozzles.
The unit weighs 136lbs. It can be remote controlled from a safe distance. The Vertidrive M3 robot has max blasting capacity of up to 1500 ft2/hr. You can find out more about it here.