I have been thinking more about heat sinks the last few days.

From what I know, the maximum time that these would be expected to run at for power is under 5 minutes. So since there is going to be very little airflow inside of bot it makes more sense to use the heat sink as thermal energy storage (ie a big block of metal). I have worked out that it would take 200g of Aluminium 5 minutes to go from 50 - 175oC when the heat dissipated is 80W from the driver. If you also factor in some convection it should be even longer. This would make it possible to make each driver board encased in an aluminium shell which would hopefully provide better protection in combat.

You would just need to watch not to burn yourself on it after the fight lol.