A life-size model of the machine will be built to run simulations
A remotely-operated 75-tonne machine nicknamed Reactorsaurus is to rip out the inner workings of a dinosaur of nuclear power production.
Engineers will create the monster to strip the defunct reactor at Dounreay in Caithness because conditions inside are too hazardous for humans.
Trials will be run on a life-sized model of Reactosaurus, before the real thing is built by 2013.
It will have two robotic arms with pincers and "roving photographic eyes".
Demolition of the site is scheduled to be completed by 2025 at a cost of about £2.5bn.
Constructed in the 1950s, Dounreay was an experimental nuclear power complex.
As well as decommissioning the coastal site, the nearby seabed is to be cleaned of radioactive particles that escaped from the plant in the past.
Reactorsaurus - which will be sent into the Prototype Fast Reactor (PFR) - is the latest in a line of inventions built to deal with hazardous waste and contaminated equipment.
Simon Coles, PFR projects delivery manager, said: "The expertise within our highly skilled in-house design team is invaluable to the PFR project delivery and innovative inventions like Reactorsaurus are one of the reasons Dounreay's leading the way with worldwide nuclear decommissioning."