Hydraulic Steering – Principles of Operation (1956) [video](youtube.com)
youtube.com
Hydraulic Steering – Principles of Operation (1956) [video]
https://www.youtube.com/watch?v=VDiOKqMKTO8
29 comments
> And as a bonus, an explanation about transistors from 1953
And here is a 1959 video from the same source about wave behavior [1].
It covers reflection from open and closed ends, superposition, standing waves and resonance, impedance mismatching, and tapered-section transformers all in a way that makes it really easy to understand.
[1] https://www.youtube.com/watch?v=DovunOxlY1k
And here is a 1959 video from the same source about wave behavior [1].
It covers reflection from open and closed ends, superposition, standing waves and resonance, impedance mismatching, and tapered-section transformers all in a way that makes it really easy to understand.
[1] https://www.youtube.com/watch?v=DovunOxlY1k
I remember watching this studying for my Extra license and it really helped!
My favorite old explainer video, telephone switching (1951): https://youtu.be/xZePwin92cI
About the Strowager Switch, which was invented by an undertaker who was fed up with the local telephone operators whom he suspected of diverting phone calls to his competitor.
About the Strowager Switch, which was invented by an undertaker who was fed up with the local telephone operators whom he suspected of diverting phone calls to his competitor.
More like "hydraulic power-assist steering" in modern terms.
With modern "hydraulic steering" it tends to imply no mechanical coupling between the steering wheel and the movement of the wheels/rudder/motor. A hydraulic leak or pressure failure therefore causes catastrophic loss of steering.
With modern "hydraulic steering" it tends to imply no mechanical coupling between the steering wheel and the movement of the wheels/rudder/motor. A hydraulic leak or pressure failure therefore causes catastrophic loss of steering.
absolutely; this is a power assist system.
actual hydraulic steering is common on boats, however. [0]
as stated , systems like this can fail catastrophically and are not often used on things like land vehicles; boats often have a fail-safe in that the rudder/motor will have a manual 'override' in the form of a manual tiller 'socket' for a wrench or emergency tiller that stays out of the water until needed.
[0]: https://www.youtube.com/watch?v=9yO4MBtk3gI
actual hydraulic steering is common on boats, however. [0]
as stated , systems like this can fail catastrophically and are not often used on things like land vehicles; boats often have a fail-safe in that the rudder/motor will have a manual 'override' in the form of a manual tiller 'socket' for a wrench or emergency tiller that stays out of the water until needed.
[0]: https://www.youtube.com/watch?v=9yO4MBtk3gI
This is a very early type of power steering gear, with the separate power cylinder and axial spool valve; I believe this is still common on very large trucks today, but in 1959 the Saginaw integral rotary-valve gear was introduced and basically became an industry standard for domestic (and some import) cars up into the 90s, and continued for light trucks after that to this day with some small variations. The accompanying integral-reservoir pump (also known as the "ham can") has also remained nearly the same over that timeframe.
Why does that title here and on YouTube say 1956 when the video itself says 1955?
Without diving into the weeds on this specific video it's quite common for film footage to show copyright | filmed on | final edit | etc dates that relate to production that don't match IMDB, library of record, etc dates that refer to the date of first public airing, the publishing date if you wish.
A difference of year (as here) is quite common.
A difference of year (as here) is quite common.
These are some of the best explanatory presentations in existence. I would love to see them analyzed to better understand how they are so effective.
It's very 1950s military.
They never mention that this is a simple feedback control system. The mechanics that maintained the thing had to know that, since it's vulnerable to the oscillation and lag problems of a simple proportional control system. Those feel like steering wheel vibration and slop to the driver. This is for an off-road heavy truck, not a sports car, so a little lag is not so bad.
The very large vehicle at the end is the M65 Atomic Cannon.
They never mention that this is a simple feedback control system. The mechanics that maintained the thing had to know that, since it's vulnerable to the oscillation and lag problems of a simple proportional control system. Those feel like steering wheel vibration and slop to the driver. This is for an off-road heavy truck, not a sports car, so a little lag is not so bad.
The very large vehicle at the end is the M65 Atomic Cannon.
The secret is in the spline!
Also: this is not how modern power steering systems work.
Also: this is not how modern power steering systems work.
> Also: this is not how modern power steering systems work.
Yes, most hydraulic systems today have been replaced by electric power steering, which uses electronic sensors to determine how much assist to apply via an electric motor. Mechanically, it is simple and very low maintenance.
Yes, most hydraulic systems today have been replaced by electric power steering, which uses electronic sensors to determine how much assist to apply via an electric motor. Mechanically, it is simple and very low maintenance.
>Yes, most hydraulic systems today have been replaced by electric power steering, which uses electronic sensors to determine how much assist to apply via an electric motor.
one small nit to pick
many modern electric power steering systems are still hydraulic by nature. It's sometimes the case that the electric motor is driving fluid to enact the resistance change. Many cars that use Bosch electronics/driving-aids still work this way, electro-hydraulic pumps in a feedback loop with pressure sensors/steering angle sensors/IMUs/vehicle dynamics sensors (speed/angle/yaw/etc).
That said, fluid-less electronic-exclusive systems now exist and are in common-use, so you're not wrong at all -- just pointing out that there are many ways to skin that cat.
one small nit to pick
many modern electric power steering systems are still hydraulic by nature. It's sometimes the case that the electric motor is driving fluid to enact the resistance change. Many cars that use Bosch electronics/driving-aids still work this way, electro-hydraulic pumps in a feedback loop with pressure sensors/steering angle sensors/IMUs/vehicle dynamics sensors (speed/angle/yaw/etc).
That said, fluid-less electronic-exclusive systems now exist and are in common-use, so you're not wrong at all -- just pointing out that there are many ways to skin that cat.
>many modern electric power steering systems are still hydraulic by nature
No they aren't. I have a car with EPS (electronic power steering) and it isn't playing any tricks. It's just an electric motor. What you are talking about is EHPS (electro-hydraulic power steering). Stop mixing up your terminology.
No they aren't. I have a car with EPS (electronic power steering) and it isn't playing any tricks. It's just an electric motor. What you are talking about is EHPS (electro-hydraulic power steering). Stop mixing up your terminology.
are you sure? there's a lot of "normal" cars that are full EPAS. Like the Prius.
I know stuff like the MR2 is like that, but I'm guessing that's because the engine is in the wrong place to have normal power steering.
I know stuff like the MR2 is like that, but I'm guessing that's because the engine is in the wrong place to have normal power steering.
Well, even before electric power steering became popular, rack and pinion steering was/is used in almost all passenger vehicles. The only vehicles that I can think of that use a steering gear and pitman arm like this video are 1 ton Ford/Chevy/Dodge and the Jeep Wrangler.
I thought recirculating ball[0] was commonly used in most passenger vehicles, and rack and pinion was more common in sports cars.
[0] https://en.m.wikipedia.org/wiki/Recirculating_ball
[0] https://en.m.wikipedia.org/wiki/Recirculating_ball
rack and pinion has been the standard for nearly all smaller passenger vehicles since at least the early 90s.
you can find things like that or like pitman arms on larger/industrial vehicles fairly commonly, though.
to your point, however, yes -- sports cars were the first ones to popularize the method. Rack and pinions tend to feel less 'sloppy' , especially after some use.
The idea stuck around in the industry though because it results in less customer complaints and requires less finesse from the mechanic during install/maintenance.
tuning a 'steering box' is a lost art relegated to hot-rod folks at this point.
you can find things like that or like pitman arms on larger/industrial vehicles fairly commonly, though.
to your point, however, yes -- sports cars were the first ones to popularize the method. Rack and pinions tend to feel less 'sloppy' , especially after some use.
The idea stuck around in the industry though because it results in less customer complaints and requires less finesse from the mechanic during install/maintenance.
tuning a 'steering box' is a lost art relegated to hot-rod folks at this point.
So was recirculating ball a halfway point between worm and sector and rack and pinion then?
We have a 1947 Willys CJ-2A, which I believe is worm and sector, though we haven't gotten into the steering yet because there are so many other things wrong with it. Including, it seems, the formerly working brakes. I discovered they had crapped out as I was backing up near a bunch of formerly neatly stacked cinder blocks.
We have a 1947 Willys CJ-2A, which I believe is worm and sector, though we haven't gotten into the steering yet because there are so many other things wrong with it. Including, it seems, the formerly working brakes. I discovered they had crapped out as I was backing up near a bunch of formerly neatly stacked cinder blocks.
Are you Mister Bean?
The only recent example I'm aware of is the Ineos Grenadier, and it's quite controversial as it means the steering is a) slow, and b) has very low self-centering (also a function of caster).
Recirculating ball steering also probably won't allow for new fangled features like active lane-keep assist, collision avoidance steering, self-parking, etc. (Which is probably not missed anyways by the 4x4 crowd, including the Ineos Grenadier ideology.) Mercedes switched their G-Class away from recirculating ball steering just a few years ago and I bet, based on MSRP, that their primary use now is much less 4x4 and much more embracing of complex computerized features for urban crawling and highway touring.
I suspect that a problem with rack and pinion 'back in the day' was materials and manufacturing mean they would wear and the steering would get sloppy. Where recirculating ball naturally is low wear. Once they upped materials and manufacturing rack and pinion was simpler and cheaper.
I think for non power assist recirculating ball is nicer because it doesn't transmit road forces back to the driver like rack and pinion does. (Could be wrong)
I think for non power assist recirculating ball is nicer because it doesn't transmit road forces back to the driver like rack and pinion does. (Could be wrong)
In 1975, your comment would be correct.
In 2005, it's horribly wrong.
In 2005, it's horribly wrong.
Doesn't the XJ have a steering box as well?
I was only looking at vehicles from this millennia. 80 series Land Cruiser and 4wd Toyota trucks from the early 90's had a steering gear too, and I'm sure some others that I don't care about.
Chevrolet Suspension (1938): https://www.youtube.com/watch?v=ej7CRAIGXow
How Differential Steering Works (1937): https://www.youtube.com/watch?v=yYAw79386WI
How A Transmission Works (1936): https://www.youtube.com/watch?v=JOLtS4VUcvQ
And as a bonus, an explanation about transistors from 1953: https://www.youtube.com/watch?v=V9xUQWo4vN0