[ozrien]

Looks like the problem is T1 is bigger than T4, and the generator isn't meant to know how to handle reducing the peak of the velocity curve.

To confirm this, first set T2 to '1' to remove the s-curving. This gives us a trapezoid. You can bump this up later to put s-curving back.

Next look at T4. T4 is dist/vprog => 4 rot / 3rps => 1333ms. If you set T1 to this the trapezoid reduces to a triangle, meaning we don't spend time any time at a velocity of vprog.

Now keep increasing T1, the generator doesn't know to add more time to the profile to make up for the loss in area due to the reduction in max-velocity (peak of the triangle). That's the limitation.

To work around that limitation, reduce Vprog to be at or below what's actually possible based on where the Velocity curve is now (peaks at about 2.5rps).

It boils down to make sure the specified vprog is obtainable. Changing T1 means changing the time between zero-speed and vprog-speed.