I got mine from LIDL and its mains operated and a wired controller held by hand. To get it up on the ramp, i screwed it to the end of the platform. On the bike, i attached a small loop of steel stranded wire for the winch hook to engage. Not seen them in LIDL lately but they are on ebay.
They are strong enough to pull a very heavy bike but really needing 2 people to be safe but you could sit on the bike and let it pull you up the slope.
As the steel rope gets near the motor, it shuts down . Great bit of kit. Not used very often but when you need it, its the dogs danglers