Electric power steering.

Copied from the SanFord thread to here for more visibility.

Do any of you gents or ladies have experience with electric power steering?

Saturn Vue power steering to be specific. The units are fairly cheap, there is a controller sold on Ebay to make them usable in just about anything.

It seems to be the easy button. Much easier than finding a steering gear that won't fit, power steering pump, hoses and all the other assorted debris.

My question is how powerful are they. Are they likely to go up in smoke if I install one in SanFord? I don't need full power steering, but a little assist in tight quarters would be nice. I would also like to reduce the diameter of the steering wheel to something smaller than a extra large pizza platter.

Thoughts? Ideas?

I installed Vue EPS in my Vangon Westfalia. It has a good sized electric motor, as long as you don't plan on autocrossing it should be okay in a heavy vehicle.

Guy in my club put one in a TR7.

They are OK-ish. They worked well for daily driven use but you can intentionally overheat them just by sawing the wheel back and forth quickly for few seconds. Then you loose power assist for 20 seconds while the motor cooled. The ION motors were even worse. In a heavier vehicle could be an issue? Just an FYI.

I spent my past life designing EPS systems. Anything sized for a passenger car will not be enough to provide assist that monster. Contrary to somewhat popular belief, those systems aren't steer by wire... just an added assist torque laid on top of what the driver provides. Most of the systems that are on the market today wouldn't provide enough assist to be noticeable in SanFord, so you'd effectively have manual steering still.

The current crop of half ton pickups has a rack and pinion based system that is quite a bit more powerful, but I'm still not sure would do the job. Even if it would, the electronics are not trivial... it isn't possible to pull a rack out of a wrecked truck and put it in something else, unless you have the right software to talk to the system, and can get the system to see the right signals (which SanFord doesn't have).

collinskl1 wrote: I spent my past life designing EPS systems. Anything sized for a passenger car will not be enough to provide assist that monster. Contrary to somewhat popular belief, those systems aren't steer by wire... just an added assist torque laid on top of what the driver provides. Most of the systems that are on the market today wouldn't provide enough assist to be noticeable in SanFord, so you'd effectively have manual steering still. The current crop of half ton pickups has a rack and pinion based system that is quite a bit more powerful, but I'm still not sure would do the job. Even if it would, the electronics are not trivial... it isn't possible to pull a rack out of a wrecked truck and put it in something else, unless you have the right software to talk to the system, and can get the system to see the right signals (which SanFord doesn't have).

While not a steer by wire system, could it be? If only for the sake of argument? Is it simply a DC motor and you could use any sort of controller with it? The controller on eBay looks pretty uncomplicated.

Let's say that I wanted to bolt it onto a gokart and make it radio controlled, or even autonomous, is this something that's possible with the correct controller/software?

In the simplest terms - yes - it is just a motor and controller. But there are various sensors and gear reductions involved as well. The OE systems use vehicle signals to determine the amount of assist required. Some of the aftermarket units replace those signals with a knob that adjusts the gain.

While it is technically possible to do true steer by wire (sensors on steering wheel and motor driving the road wheels with nothing in between), it isn't something that I would be comfortable with personally at a DIY level. The OE automotive world isn't doing steer by wire yet because of the whole if something fails, there is no directional control thing. The current systems have the mechanical linkage still there if the electronics give up the magic smoke.

In reply to Toyman01:

I can't see an electric assist steering system working in Sanford. The one that you are looking at is from a small car, but I can tell you that even the heavy duty ones that are in some electric forklifts are troublesome.

There may be a way to put a hydraulic assist in the column if you can figure out how to get a pump on the engine, however, if you have a pump on the engine a conventional power steering box is probably a better idea.

I have to defer to cillinskl1....however, my thoughts are that you are adding assist to what is already there. Since the buss is already drivable, it's not like you are asking the assistmotor to do anything it was not meant to do; the bus will still have the high ratio steering box that allows you to drive unassisted.

collinskl1 wrote: In the simplest terms - yes - it is just a motor and controller. But there are various sensors and gear reductions involved as well. The OE systems use vehicle signals to determine the amount of assist required. Some of the aftermarket units replace those signals with a knob that adjusts the gain. While it is technically possible to do true steer by wire (sensors on steering wheel and motor driving the road wheels with nothing in between), it isn't something that I would be comfortable with personally at a DIY level. The OE automotive world isn't doing steer by wire yet because of the whole if something fails, there is no directional control thing. The current systems have the mechanical linkage still there if the electronics give up the magic smoke.

This would be something that never, EVER, would be on the street and more of an engineering project. Working on something for my capstone project. I'd be writing the code myself and coming up with a controller, but if it's just a simple DC motor that could be controlled not unlike any other DC motor, it isn't a huge issue.

I know some of the modern dwarf car guys are using some sort of electro-hyro torque booster. but not sure what it is.

Zzw30 ones are super simple to retrofit. Might not be the answer here but they need no sensors just switched/power and ground iirc. I'm doing one in my ls/hilux and will have more info soon. A google search reveals a wealth of info.

collinskl1 wrote: In the simplest terms - yes - it is just a motor and controller. But there are various sensors and gear reductions involved as well. The OE systems use vehicle signals to determine the amount of assist required. Some of the aftermarket units replace those signals with a knob that adjusts the gain. While it is technically possible to do true steer by wire (sensors on steering wheel and motor driving the road wheels with nothing in between), it isn't something that I would be comfortable with personally at a DIY level. The OE automotive world isn't doing steer by wire yet because of the whole if something fails, there is no directional control thing. The current systems have the mechanical linkage still there if the electronics give up the magic smoke.

Last I knew, there was a legal requirement to have a mechanical connection between the steering wheel and the front tires. Otherwise, manufacturers would have gone to a pure hydraulic system long ago.

snailmont5oh wrote:

collinskl1 wrote: In the simplest terms - yes - it is just a motor and controller. But there are various sensors and gear reductions involved as well. The OE systems use vehicle signals to determine the amount of assist required. Some of the aftermarket units replace those signals with a knob that adjusts the gain. While it is technically possible to do true steer by wire (sensors on steering wheel and motor driving the road wheels with nothing in between), it isn't something that I would be comfortable with personally at a DIY level. The OE automotive world isn't doing steer by wire yet because of the whole if something fails, there is no directional control thing. The current systems have the mechanical linkage still there if the electronics give up the magic smoke.

Last I knew, there was a legal requirement to have a mechanical connection between the steering wheel and the front tires. Otherwise, manufacturers would have gone to a pure hydraulic system long ago.

Didn't infinity and Mercedes botg do steer by wire already? Iirc there was a big recall with the infinity one already.

https://www.google.com/amp/s/www.wired.com/2014/06/infiniti-q50-steer-by-wire/amp/

Those systems have a clutch in the mechanical linkage that will disengage in the event something goes wrong. So basically there is a lot of extra mass and complexity along for the ride just in case.

Wired article said: If Infiniti ever has the guts to go for the lobotomy and strip out the mechanical steering system (it left it in there as a backup), it could cut the car’s weight and boost fuel economy.

Didnt the MR2 have a electric motor operating a pump and still used a hydraulic pump. Maybe its enough to run a rack.