Tiberius is only one robot that only sometimes fights, if you ask the guys not to put a hole in your robot they usually don't.
My experience of kan Opener is the pincers only go through about 50-60mm tops then the resistance of the HDPE equals
the crushing force so if you have an air gap between the armour and the soft stuff you should be OK. remember the shape of the Tiberius beak,
means it can only nibble the edges.
The bottom line this game is paper, rock scissors you will not make the perfect robot.