In Cab Operated Electric Telescoping Trailer Tongue
 

My design to draw a trailer up for highway aerodynamics, and extend it back for tight turns around town. All done without having to leave the car.
https://www.youtube.com/watch?v=UyYONaqJ8zU

After I designed this, I found the heavy duty, probably hydraulically operated, version on You Tube. Their version uses lock pins. My version counts on the gearmotor to prevent creep back. I will have a red light in the car to tell me that the trailer is pulled up tight, and if it creeps back, the light will go off, and I will push the "Draw Up" button. But I think the gear reduction in the gearmotor will be hard to run backwards through the all thread.
Here is the commercial version:
https://www.youtube.com/watch?v=KY0ugxC8RPo

I'm bothered by the way the inner or outer surface of each square tube is a bearing surface. Teflon buttons or something?

Why couldn't you have the motor at the hitch end? Could you get the gear drive inside the 3 1/2" pipe? Cut out two sides of the pipe and box the opening?

Good suggestion. I'd have to use the .188 wall 3 1/2 inch tube in place of the .250 wall to make room for the buttons. Hope the mild steel won't bend.

Just seemed more sturdy to keep the front tube intact, and go into the non-load bearing end of the rear tube. I may overhang the carrier a bit, and protect the motor from rain.The Teflon idea is good, though. Will let me use lighter tubing.

I AM a bit concerned about the shortened wheel base in Highway Mode. I've heard that shorter trailers are more skittish.

I was taught that it's the ratio between the TV axle/hitch and hitch/trailer axle. Moving the hitch closer to the tow vehicle axle is [proportionally] equivalent to lengthening the tongue.

slowmover can tell you about a swinging hitch that does something similar. I don't recall the brand name or how it locks (or not).

How can I find his posts?

A Jim Hensley patented hitch locks & unlocks. 120# without vehicle hitch receiver.

PULL RITE used to make a swinging constant-distance hitch. But it weighed over 400#.

I’ve my doubts this’d work well (ROI), but pulling the trailer innclosexwouldnt otherwise concern me.

Moving the trailer axle rearward on trailer frame is an old method for better stability. But can trailer design handle it? It increases forces at other end (strain).

My design keeps the load centered over the axle, moving the load and axle as one unit. Only thing I see is that the horizontal center of gravity moves forward slower than the load and axle as the trailer is drawn up to the tow vehicle. Would need to locate the axle so that at full forward, there is still 200 lbs on the ball, but as the trailer tongue extends, that ball weight would increase.
(Have I got this backwards?)