Rotating Ballnut - design ideas

[Jonathan]

Great project and racing at Isle of Man wow respect that place is nuts.

You can certainly say that of the riders!

I'd like to remove the rotating mass to improve my accelerations. The gantry it moves weighs around 150KG I estimate.

With that size ballscrew then you do have a problem with the rotating inertia, not so much the 150kg gantry. Can you measure the ballnut - approximate it as cylinders, then we can work out the inertia of the ballnut compared to the ballscrew to see what you could gain by rotating the nut.

So I am wondering are you interested in building me a ball nut for this? Happy to pay market rates of course and if it helps fund any of your emoto projects then all the better.

My PhD studies are taking up a lot of time at the moment (need to catch up after all the racing!), but I do intend to have time to finish some rotating nut assemblies soon.

Below is my final servo response I got recently which I am really stoked about it

What else can you plot from your system - can you plot the motor torque in addition to the speed response? If so, that's another way to work out the inertia and get better insight into how the system will behave.