There's one problem with carrying your bicycle on a car-top rack – you might forget that the bike is up there when you pull into your garage, a drive-thru or a parkade, so you end up smashing it. Well, that's why Raacked was created. It's designed to warn you when you're approaching overhead obstacles that your car-topped bike (or other item) won't clear.
Raacked consists of a waterproof device that is mounted on your roof rack, which communicates wirelessly with a USB-dongle-type receiver inside the vehicle.
Once activated, the rack-mounted device continuously sends out ultrasound pulses. When these are reflected back by an obstacle located at bike-on-the-roof height, within a range of 4 to 12 feet (1.2 to 3.7 m) in front of the car, they're detected by that device. It in turn causes the in-vehicle receiver to beep, warning the driver to stop. The closer the car gets to the obstacle, the faster the receiver beeps.
Plans call for the system to be the subject of a Kickstarter campaign, which potential backers can register to be notified about via the link at the bottom of the page. We're told that the retail price should be around US$125.
That's a little less than the HeadsUp system, which doesn't actually detect overhead obstacles, but does remind drivers that their bike is up there as they approach their garage.
Raacked is demonstrated in the following video.