They can't scale infinitely. They can fit finitely many robots close to the target. The further the robots get from the target, the longer and thus heavier the

They can't scale infinitely. They can fit finitely many robots close to the target. The further the robots get from the target, the longer and thus heavier the tether they need. The more interesting part of the ant behaviour, not addressed yet here, is how they use each other's bodies as tethers and arrange forces so they add up in the right direction.