Auto-retracting spool for auto-towing gliders?

Does anyone know of auto-towing gear that will automatically retract the rope the glider releases?

My club has just moved to a new airport, which has a runway long enough for auto-towing. However, we'd like to be able to clean up the runway quickly -- preferably while the tow vehicle is still moving.

Any pointers would be appreciated.

It's worth mentioning that my club has at least three active members who've done auto-towing in the past, so we have some idea what we would be getting in to. We also have some fabrication abilities. I'm just looking for pointers to good designs (or devices we can buy) to update our gear.

Thanks,
-Luke