No two ice sheets have ever been laid down the exact same way, both because of this random bumpiness, and because of the quality of the water used, which can affect the way the liquid hardens into a surface. Accordingly, human curlers are allowed to take practice throws before a match to get a feel for the ice. All that imperfection only grows more chaotic as the game goes on, as the friction from the stones modifies the ice.
What does this mean for an ice-going, stone-throwing robot? Well, if a human or Curly were to somehow throw two stones the exact same way, the stones still wouldn’t take the exact same path. “Stone throwing for humans or for robots is imperfect, and it’s imperfect for various reasons,” says Müller. “One reason is that it’s impossible to judge the ice quality.”
The equations in the researchers’ curling