RS-550 DC motor controller 24V (35-70) A working range and a stall of 120A
How soon is this robotics challenge? Unless it's sometime in 2025 I can tell you from experience that you probably aren't going to be able to build one in time. People that understand how to drive high power MOSFETS at high frequencies don't seem to want to share their knowledge. Go buy a Sabertooth 2x50 from Dimension Engineering and be done with it.