That robot is dumb.

You'll be traction limited to a ridiculous intent. Your power to weight ratio is ~0.47hp/kg, which is well into supercar territory - a Ferrari 430 in full race spec has about 0.38hp/kg. With those shuffling feet, you will never be able to get the power down.

Also, those motors draw more than 50kw total at 72 volts. 9 battlepacks won't cut it, try about 10 strings of 3 24v 3.6ah - which will total 30 battlepacks, at 55kg of just batteries.

And even those will melt if the motors ever stall - at stall torque they'll draw about 3kA.

The kind of speed controllers you'd need would be insane too - they'd have to be custom jobs using H-bridges of industrial IGBT bricks - add 10kg at least just for the controls.