need some help with sinusoidal movement of axis

[A_Camera]

I am trying to build a paddle to create waves in a water tank. I have built a linear drive with ballscrew and plastic nut, stainless steel bearing driven with a hybrid stepper and HSS86 leadshine type drive. Currently the max I can drive the motor is approx 4000 rpm with a UC300eth and bob. My original idea was to drive the one axis from the bob, using a circular G2 command sending the other axis not connected through the bob. I could maybe use a formula or vb code but not that savvy on these commands. Basically want to oscillate the axis or table around a zero position and have feedrate control and be able to cycle this in the smoothest possible manner for different radius. Any suggestions for the best method?

This sounds overcomplicated to me or I don't understand what you are trying to do. Why not just use a simple ordinary motor to do this? The motor shaft should drive the paddle up and down creating the waves. A speed regulator could be used to adjust the speed of the motor. I don't understand why use a stepper and a UC300ETH for this project, or how you plan driving the motor. The UC300ETH requires some software as well, like the Mach3 or UCCNC. With those you can write and run a macro, or run G code in a loop to do it, but it seems very complicated for this simple task.

[magicniner]

A Scotch Yoke with the drive pin mounting point adjustable for radius, a variable speed drive for the motor, tachometer on the shaft of the Scotch Yoke.

That gives you variable amplitude from zero to the size limitation of the Scotch Yoke you build, with variable speeds from zero to things you could only dream of with steppers ;-)

[donkeyot]

A Scotch Yoke with the drive pin mounting point adjustable for radius, a variable speed drive for the motor, tachometer on the shaft of the Scotch Yoke.

That gives you variable amplitude from zero to the size limitation of the Scotch Yoke you build, with variable speeds from zero to things you could only dream of with steppers ;-)