Build a automatic drone!(Radar Drone)

Build a auto drone that can fly to the goal.
Don't build a car!!!
Contest ends until 10 or more entries
Rules:
1.No manual controllers. All things are controlled by itself.
2.Lua is allowed
3.No entity:warp() lua function.
4.Do not modify anything of the world.
5.You can't use the bug to go through walls.
6.Build in the building area.
7.Your drone mustn't be too large(of course)