Controller design for sinuisoidal reference signal
If you know the frequency of the reference signal, using the model of the input signal (\$1\over s^2 + \omega^2\$) in your controller can help you to track it, similar to the integrators (\$\frac{1}{s}\$) needed in the control to track a step input (\$\frac{1}{s}\$) and 2 integrators (\$\frac{1}{s^2}\$) to track a ramp input (\$\frac{1}{s^2}\$) as seen in https://www.youtube.com/watch?v=hG7dq-51AAg