Instead of this amazing high-tech device, I should just hang a rope from a truss in my garage, just in front of where my front bumper usually is, and tie several knots in it to help pull myself up off my creeper.
While talking creepers, this might be a good idea:
(Beware, from reading the comments below the video on the youtube page, I'm glad I watched it with the sound off.)
https://www.youtube.com/watch?v=1cNSfuBAApI