Electric power steering
 

Ok so from this pic
http://i223.photobucket.com/albums/d...n/e63e7a4a.jpg
we can see that the FT will have EPS. my immediate reaction is :thumbdown: , of course, but then...

https://docs.google.com/viewer?pid=b...mber=17&w=2000
it turns out the LF-A has column mounted electric power steering! conventionally, column mounted has the worst feel over pinion mounted and rack mounted, but the LF-A has great steering feel!!! THIS is why you have a halo car. THIS is why the LF-A costs so much. they've managed to make electric power steering great. so all those hours spent tuning the steering? it trickles down into $20k cars like the FT, hopefully :thumbup:

so what does all this mean? it means toyota knows how to make EPS great. sure a corolla or yaris isnt going to have similar steering feel/EPS tuning, but the FT was made with the same sporting intentions as the LF-A. it's supposed to be a bac to basics kinda car with as little intervention as possible. what better steering system to emulate? it would not surprise me if the steering of this car turns out to be LF-A good. and for an EPS system? that is HIGH praise...

The column mounted EPS was also one of my main concerns about this car.

I've never realized that the LFA also uses the same type of EPS system, but if Toyota can do it then lets hope they also do the same with the FT86. :clap:

Are you sure the power steering is done by toyota? Subaru also makes an EAPS system.

My RX8 has electric power steering, it feels great.. This is different to drive by wire ;)

As long as we're talking about the steering system, this is a patent that was published last week assigned to Fuji Heavy Industries (Subaru.) As with many patents, it tends to be rather vague as to what vehicle it goes to. That in mind, it describes a system for mechanical steering.

Quote from the first page:
"Moreover, since the steering gear ratio can be changed mechanically without performing motor control, the occurrence of control delay can be prevented, thereby reliably preventing deterioration of the driver's operational feel"

So whatever car this system is going on, it seems like they really want road feedback and driver experience to be key. Which, seems to be what they've been saying all along for the FR-S/BRZ/Whatever.

And here's another patent from Fuji Heavy Industries describing an electric power steering unit published back in July.

i dunno how i feel about variable steering ratios. BMW's active steering hasnt been such a hit. i have a feeling this patent isnt for this car. steering is absolutely important in this back to basics car. variable ratio is not necessary. i personally want it quick all the time ;)

RX8 uses rack mounted EPS. This is column mounted, which is known for having terrible feel.

I dunno, I'd rather have a mechanical power steering system with variable ratio over a column mounted EPS system any day of the week. How would column mounted EPS be more "back to the basics" than mechanical, regardless of variable steering ratios or not.

As long as the variable steering is quick for all but the very extremes of wheel angles (yes I'd prefer non variable as well, but in this world of EPS systems I'd love ANY mech system instead!) then I think it'll be great to have the system that patent is for... and it does seem like a potentially good sign that the patent seems focused on driver involvement, exactly what Toyota and Subaru say this car was designed for.

I, too, would rather have the mechanical steering. I've driven a few new cars that had electric power steering, and every single one felt dead to the road. Personally, I miss how much feedback I got from my Celica.

But, on the other hand, I don't want the system to be so mechanically stupid as to be almost impossible to turn the wheel when the car is stationary. It was a workout to wrestle with the wheel in my old Toyota pickup.

there's no point in talking about mechanical steering. it looks like 99.999% chance that it's EPS. fwiw the new 991 porsche 911 has EPS so its a sign of the times. Im just glad and optimistic that toyota has shown that they can make a column mounted EPS that doesnt outright suck.

Well if Subaru just filed a patent now than the rest of us can keep the hope alive that it won't be a POS EPS system :)

I'm pretty sure all or most cars are using mechanical steering as I don't think steer-by-wire is offered right now.

The difference is that the steering is power assisted with electric motors instead of using hydraulic pumps.
All in all this is encouraging news. :)

in terms of this discussion, it's assumed "mechanical steering" means hydraulic power steering.

Yes but to reduce misunderstanding for others I believe it is a good idea to clarify it.

One idea someone had a while back was to have a switch for the power steering: assist when you don't want to wrestle with the wheel in a parking lot, no assist (or less) otherwise. Possible mod? :O

Why do people want no assist? You want a workout while driving? LOL

Seriously though, power steering is a must for enduros.

a button to turn off PS? that'd be liability heaven... :bellyroll:

but seriously, all it needs is good tuning. EPS is still in it's relative infancy. with time, technology, and experience, im confident that once all the kinks get ironed out, it will be as good, or perhaps even better than, hydraulic PS....

My Lexus ISF has electric power steering, my Honda Accord Euro has it too. Most new cars are coming out with EPS. I don't see what all the fuss is about?

Cause everybody wants back carbs, drum brakes and hand crank starters man.

Lol not exactly. Eps offers zero benefits to the driver over mechanical steering but does take feel and feedback away. The other examples you gave were all replaced with items that add to drive enjoyment (lack of having to deal with a cab, better braking and convenience).

Most power steering systems are already zero or low assist at speed so it's basically built into it already. full assist at speed isn't a good idea which is why they created variable assist systems.

SteerByWire takes the feel away if there is no feedback motor in the wheel.. Electronically assisted steering doesn't.. It works exactly the same way as hydraulic assisted steering but with a electronic motor rather than hydraulic.. The steering wheel is still directly connected to the rack, which is connected to the wheels.. There is a lot of confusion and misinformation on this thread. If you want proper feel of the road, don't have power steering :p
Benefit of EPS is that if you stall, you can still steer with ease and not crash ;)
My rwd car has EPS and when I hit a pothole I feel it, when I hit a bump I feel it, when I hit a groove in the road I feel the wheel puling.. When I drive my gfs car I can feel the torque steer (fwd, eps)
So I don't know what your talking about

This is directed at everyone whos whinging You can yell at logic all you want but you won't win ;) If you don't like it, and can't advance with technology, go and cry your self to sleep

The new Porsche 911 (991) (2012) now also has EPS instead of HPS.

What current cars have the sort of EPS that we are speculating will be on the FT?

0 parasitic loss. Better variability in assist for low speed vs none @ high speeds maneuvering.

I don't know much about EPS, but the one in my IS is numb and hard to steer. I hope Toyota/Subaru will fix that problem.

Sorry, but I'm laughing my arse off here about the talk about Steer-by-wire. This is not happening, and will not happen until we start using joysticks to drive cars....

by-wire means there is NO DIRECT MECHANICAL CONNECTION ie NO Physical connection between the steering wheel and the wheels... anyone trust electrics 100% with theirs and others lives? I know I don't!

theoretically it can be programmed to tune out unwanted motions such as bumpsteer, tramlining and torque steer.

it depends on the design and the tuning. as stated above, if taken too far the system can tune out all steering feel, and it can also overboost the steering and the steering would feel super light at all speeds. good for the geriatric population, but not for enthusiasts..

LF-A!!! which bodes well for the FT imo...

another plus for EPS is that you can change this with a simple software update! of course toyota would probably never do this, but theoretically if you crack the ecu you can do it yourself with tuning software. even so i doubt anybody would be crazy enough to mess around with that but the point remains that changes can be easily done with software and not hardware.

You read my mind.

When I had the Supra, we did a rather complicated power-steering delete (needed a specialized bracket made for the alternator to re-tension the now totally different belt). It is heaven when driving. Hell when parking.

So I was looking into a 12V DC hydraulic pump that could be attached to the original rack to power it with a switch (instead of silly speed-sensitive crap). This would take back some of the weight savings, but make everyday life easier. But it seemed complicated, and wasn't my daily so I decided to live with it.

Can any MR2 guys tell me if the SW20 used an electric pump for their steering?

(What I'm talking about is I think what they call electro-hydraulic steering.)


If the FT86 can use a pure electric that feels as good as no-power but with a parking boost toggle, that would be awesome.

The problem with electro-hydraulic is it's adding a lot of complexity for a relatively small improvement. Electric steering uses energy only when it needs it, hydraulic always needs the system to be pressurized and most of the time you don't need this. It makes more sense on something like the Mclaren MP4-12C, where it has fully active suspension which is hydraulically powered, so they just used it to power the steering as well.

I used the MR2 electric power steering pump on my rx7, and it worked fine. Like my factory system, it was RPM sensitive. So i think the pump would stop working at speeds over 20mph.

What i liked about it was the fact that it took strain off the engine via belts. and it allowed me to use a gilmer pully system while retaining PS.

But eventually i went with a manual steering rack soon as i scored a quick ratio manual steering rack for my car.

Id go back to power steering if i get a larger wheel width over 8.5 or any bigger than 255.

Any of you who have tried to turn a car with a +275 width tire on a manual rack would know what im talking about...its virtually impossible even for a body builder.

XT6 has electric power steering pump. There are a few problems like the comuntator wearing out I think? I never had that problem on any of mine.

Every review I've read about a new model with EPS replacing an old one with HPS says the new model has inferior steering feel.

The S2000 has EPS and (after lack of low end torque) that car's biggest criticism is numb steering/bad steering feedback.

Give me HPS any day of the week. Better feel.