Originally Posted by Freebase Dali

Look for an effect pedal that uses an LFO to automatically control your LP filter and allows you to set the frequency of the oscillations. Obviously, a manual resonance control will also come in handy if you want your sweeps to be defined.

What this basically is, is a wah pedal... except you're not manually controlling it. I know you're thinking 'auto-wah', but auto-wah uses additional parameters like threshold and other things. If you can get an auto-wah pedal that actually lets you change all its parameters extensively, you'll have what you're looking for.