Tunnel Boring Machine

The robots are picking carrots. The blue robot's driving the combine harvester. What's this? A horse has run onto the field. The robot turns the wheel to avoid a collision. Kaboom... The combine harvester's toppled over and has broken down. They'll have to take the combine harvester to be repaired. The combine harvester's too big and won't fit in the tunnel. The group are going to build a tunnel boring machine to make the tunnel wider.