The road is one of three major infrastructure projects and is expected to cost more than £400m.
The new facility is based in Culham, Oxfordshire, helps scientists manage and analyse the fusion process.
The government says growth zones - of which Oxfordshire is the first - will deliver "untold opportunities".
The UK Atomic Energy Authority developed the robot with the European nuclear research centre, Cern.
The so-called "HIF1" project will see a new bypass, Thames crossing and railway bridge built.
The Europa School in Culham will no longer receive an uplift for teaching a more intense programme, under government plans.
The facility near Culham Campus was rejected by South Oxfordshire District Council last year.
The funding is split between projects in Oxfordshire, Nottinghamshire and Yorkshire.
The facility will be used to recover tritium - a key component in nuclear fusion.
