The “fifth wheel” parallel parking tool that never hit it big (2018)

Very interesting, I guess one of the reasons it didnt take off because it wasted so much space in the boot

There was another idea I remember reading about in the 70s or 80s in (I think) Omni Magazine: Four wheel steering: All four wheels can be rotated. with the steering wheel. Turn the wheels to a full 90° and you can then move the car sideways into a parallel space. A lot more practical than this plan which pretty much destroys all the trunk space. Especially, with an EV where you can connect motors directly to each wheel, I can see this working out very nicely.

I think it never made it big because:

1. Thinking about having to parallel park makes sure you are less likely to bump the cars in front and behind. Moving the front in and then swinging the back in seems like a good way to swing the back into another car.

2. Parking wasn't as much of a nightmare in the early 30s. Then WWII happened and that metal would have been an excess. By the 50s it was a "failed" idea.

Having 90 degree car wheels (that can only go 90 degrees at ~rest) combined with the sensors on a modern EV might make it feasible. But I'm not a mechanical engineer so "90 degree car wheels" might have some other feasibility problems, even at rest.

Mitsubishi (and others) in the 80s,90s had 4 wheel steering:

  https://en.wikipedia.org/wiki/Steering#Four-wheel_steering

  https://www.autoweek.com/car-life/a1871191/four-wheel-steering-demystified/

I never drove one; I had a friend that said it really didn't do much for him that he noticed.

The advantages of four wheel steering at driving speeds are largely (completely?) negated by active traction control (supplying power and breaking to each wheel independently). You're not going to see a car turn its wheels 90 degrees because of both the large space needed (the cavity for the wheel to turn in) plus the complexity of linkages that can handle that amount of turning.

This idea might make more sense today than it did back in the day because you can put a small electric hub-motor on the fifth wheel. Downside is that cars are far heavier now than in the 30s so you'd need a beefier lift for the fifth wheel.

[edit]

Looks like Porsche and Renault offer 4-wheel steering in their high-end cars today, which suggest I am wrong about active traction control completely negating the advantages at high speeds.