Mimic gesture to drive UIPickerview

Bear with me. I did some investigations.

What I want, is a UIPickerview to behave as if it was operated by me, the user.

I know this:

self.picker.selectRow(43, inComponent: 0, animated: true)

but that doesn't include the scroll speed and the slow down.

I'm looking for something that I can operate as follows:

 func scroll(picker:UIPickerView, direction: Int, speed: Double){        // I might need some callback, but this would be great already.        // likely, the parameters would include a simulated Gesture, but I don't know how to do that    }

I hope somebody understands what I mean

thanks