We should try using these formulas:
Turn Velocity: V = 4r √((TGθ) / (Rm))
where r = half of' distance between wheels
T = max torque of wheels
G = gear ratio
θ = rotational distance to end of turn
R = radius of wheels
m = mass
Move Velocity: V = √(8TGd) / (R*m))
where T = max torque of wheels
G = gear ratio
d = distance remaining
R = radius of wheels
m = mass
G = gear ratio