snopes.com

snopes.com (http://message.snopes.com/index.php)
-   Automobiles (http://message.snopes.com/forumdisplay.php?f=2)
-   -   Parking in 1927 (http://message.snopes.com/showthread.php?t=95791)

RichardM 23 June 2017 08:53 PM

Parking in 1927
 
https://www.google.com/#q=parking+problem+solved+1927

Okay, this doesn't look real to me. Who can disprove this?

ETA: Won't link. Will try again. Maybe this works.

WildaBeast 23 June 2017 09:05 PM

Cars back then would have all been rear wheel drive, I would think. Sending power to the rear wheels would probably just make the car plow forward on the sideways front wheels, not spin in a circle like that. The front wheels would have to be powered somehow.

ETA: Maybe if you did something to the differential so only one of the rear wheels would be powered... but even then I don't think it would spin like that. Maybe if you could somehow make one of them turn forward and the other turn backward, which after rewatching the video is what appears to be happening. ETA2: Which now that I think about is basically how a zero turning radius mower works.

Psihala 23 June 2017 09:22 PM

Quote:

Originally Posted by RichardM (Post 1952349)
https://www.google.com/#q=parking+problem+solved+1927

Okay, this doesn't look real to me. Who can disprove this?

ETA: Won't link. Will try again. Maybe this works.

Your search link includes the entry to the 1927 Pathť source film. While I won't go so far to say that it "proves" anything (particularly after reading the catalogue description), the film itself seems genuine.

~Psihala

RichardM 24 June 2017 01:16 AM

I'm hoping that someone can prove the film is not really that old or something like it may have trickery from 1927. What I see is a rear wheel drive car. This is evident by the rear axle with a differential being clearly visible. No tie rod can be seen in the views of the front wheels. In fact the area where the tie rods would connect have been obscured. The movement of the car is consistent with each front wheel or maybe just one being powered, perhaps by an electric motor. Other than that, I can't tell you much else.

UEL 24 June 2017 01:25 AM

Three observations:

- the car is always turning counter-clockwise. Three examples, three counter-clockwise turns. Does it only work in one direction?
- every time there is a transition either to or from the funky turn, there is a major cut in the footage. This hints to me that there had to be some mechanical adjustments (locking hubs, mechanical switching at the axle etc) in order to get this to work correctly
- each demonstration of the funky turn has someone sitting in the rear seat. Is this just a matter of that person being the assistant (or relative) of the driver/inventor and getting into a film? Or is that person a functional part of making the car turn?

It is a neat film. I suspect that if anything, it was a proof of concept that never took off (too much work to make it happen). I'd love to see more of the stuff from that era.

ChasFink 26 June 2017 12:34 PM

Quote:

Originally Posted by UEL (Post 1952366)
I suspect that if anything, it was a proof of concept that never took off...

I agree. This certainly would have been possible at the time, but the car seen here was likely just a prototype that would be impractical in everyday use.

Richard W 26 June 2017 12:58 PM

During the spins, the rear wheels are definitely being powered in opposite directions, with the right rear wheel turning forward and the left one turning backwards. I think that would give the effect you see without needing to power the front wheels.

(eta) UEL, after the first cut, somebody actually gets into the rear seat between the car driving up (no rear passenger) and the spin (rear passenger suddenly appears). That's one thing that makes the cut obvious, as otherwise, with the jerky film and fixed camera, the cuts are easy to miss. It does suggest that he's doing something necessary back there.

overyonder 26 June 2017 01:03 PM

It's fairly straightforward to make the wheels turn to nearly 90-degree. Since they are not driven (not power to them), there are no axles/universal-joint to bind.

As for the rear, it's quite possible to use what's called a cutting brake, which is in effect 2 independently actually parking brakes. Instead of having one pedal or handle that is split to both wheels, 2 handles are used, one to each side. That's fairly common in sandrails (aka "dune buggies").

OY

thorny locust 26 June 2017 01:57 PM

Quote:

Originally Posted by overyonder (Post 1952480)
As for the rear, it's quite possible to use what's called a cutting brake, which is in effect 2 independently actually parking brakes. Instead of having one pedal or handle that is split to both wheels, 2 handles are used, one to each side. That's fairly common in sandrails (aka "dune buggies").

It's entirely standard on farm tractors. When making tight turns, one steers with the brakes as well as with the steering wheel.

-- since people driving farm tractors often turn much more frequently in one direction than the other (circling through the field in a pattern requiring turning primarily in one direction), one brake often wears more than the other, and if one's going down the road at some speed and needs to step on the brakes it's wise to be aware that stepping on both equally may slew the tractor sideways. I don't know whether that's a problem with sandrails; very likely the particular driving pattern that wears one brake more than the other only comes up in open field operations.

crocoduck_hunter 26 June 2017 02:27 PM

I think I read a book in grade school that mentioned a car like this as an idea that never took off.

overyonder 26 June 2017 06:27 PM

Quote:

Originally Posted by thorny locust (Post 1952488)
It's entirely standard on farm tractors. When making tight turns, one steers with the brakes as well as with the steering wheel.

Since I never drive tractors it never came to mind but it's quite accurate now that I think about it.

OY

WildaBeast 26 June 2017 06:39 PM

Quote:

Originally Posted by overyonder (Post 1952480)
As for the rear, it's quite possible to use what's called a cutting brake, which is in effect 2 independently actually parking brakes. Instead of having one pedal or handle that is split to both wheels, 2 handles are used, one to each side. That's fairly common in sandrails (aka "dune buggies").

OY

Yeah, but it looks to me like the rear wheels are actually turning in opposite directions, one side turning forwards and the other turning backwards. Simply having separate left and right brakes wouldn't do that. You'd need some kind of special gearing to accomplish that.

DrRocket 26 June 2017 10:40 PM

The passenger in the back definitely seems to be a required part of the process.

At the end of the film in what appears to be an open courtyard, if you look closely, you can see him holding what appears to be some sort of lever or control. (The camera is shooting from a higher viewpoint.)

The car never turns without someone back there.

Plus, there's that plate in front. While you might think it's a license plate, it appears to be hand painted. I think that plate is there to hide the front mechanism used to flatten the front wheels from the camera.

RichardM 08 July 2017 04:04 PM

First, an explanation of how this could be done:

The tie rods are disconnected from each front wheel. The tie rods connect the front wheels to each other. See https://en.wikipedia.org/wiki/Steering If the tie rods are connected, the front wheel can not rotate the full 90 degrees shown.

Once the front wheels are in position, power is applied to one of them. The rear wheels turn opposite directions because this car has a common open differential. I know this from experience. See http://auto.howstuffworks.com/differential1.htm for more information.

The question I have is whether or not this was done with the machinery mounted on the car or if this was done by mechanics not shown in the film manually disconnecting the tie rods, manually turning the wheels and then installing an electric motor to drive the right front wheel.

BrianB 09 July 2017 12:17 AM

Was CitroŽn first with parking assist back in 1927?
 
https://citroenvie.com/was-citroen-f...-back-in-1927/

Quote:

Some have said the car is a Peugeot, but no, Ė it is a CitroŽn B12 Torpedo. Not sure if the 90 degree front wheel modification to demonstrate this parking innovation was something engineered by CitroŽn or someone else, but the car is definitely a CitroŽn B12 Torpedo!
Brian

blinkingblythe 14 July 2017 05:18 AM

Quote:

Originally Posted by RichardM (Post 1952365)
I'm hoping that someone can prove the film is not really that old or something like it may have trickery from 1927. What I see is a rear wheel drive car. This is evident by the rear axle with a differential being clearly visible. No tie rod can be seen in the views of the front wheels. In fact the area where the tie rods would connect have been obscured. The movement of the car is consistent with each front wheel or maybe just one being powered, perhaps by an electric motor. Other than that, I can't tell you much else.

It looks like the man in the back seat is turning a crank or something which leads me to believe the front wheels are manualy operated simaler too
a pedal bike. An electric motor and battery powerful enough to run the front wheels would have been very expensive in that time, so this was most likely manualy operated.

As another poster said, this looks like a proof of concept that never took off, likely because the car needed two drivers (one for driving the car and the
other to operate the crank mechanism for parking mode.) to be at all practical.

Richard W 23 September 2017 11:46 PM

Again, you really wouldn't need to power the front wheels (manually or otherwise) to do that if the rear wheels were being powered in opposite directions. The rear wheels certainly seem to be turning in opposite directions.

The question is really what needs to be done to the car in order to switch it from "rear wheels both going forwards" mode to "rear wheels turning in opposite directions" mode. (eta) And also, possibly, from "front wheels at sensible driving angle" mode to "front wheels at 90 degrees to forwards" mode, although to me that seems more straightforward, as it were - I don't see why it has to be anything other than an extreme steering lock. It seems clear that it must involve more adjustments than they're pretending, and the guy sitting in the back doing something to enable it, but I don't see how we could tell any more than that just from looking at the video. The trickery involved isn't video trickery, except for the somewhat disguised cuts...

Gutter Monkey 24 September 2017 06:20 AM

Here's a 1950s version of the technique!

<iframe width="560" height="315" src="https://www.youtube.com/embed/fJrGKHMXtVU" frameborder="0" allowfullscreen></iframe>

Gutter Monkey 24 September 2017 06:34 AM

By the way, if you do a google search for a key word, a year and 'patent' is brings up all the patents for those inventions in that year. A search for 'parking patent 1927' brings up a few things but I don't know enough about the mechanics involved to know if any one them might be related to this.

https://www.google.com/search?tbm=pt...ng+patent+1927

I guess searching a few years before and after 1927 might also be helpful, also more precise key words than 'parking'.

RichardM 24 September 2017 03:20 PM

Also, the patent search probably should be in France.


All times are GMT. The time now is 09:26 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.