bathroom fan

My bathroom fan is on a wall switch; this turns the fan on and off, but you still need to open the vent manually (too high for wife to do).

Is there a fan/vent unit available that turns on the fan, and opens the vent when powered on, and then closes the vent when powered off. There are covers that can be installed to allow the vent to stay open; I'm not a fan of them.,

Thanks,
Doug