Frex SimWheel

Hi All,

I'm intrigued by the top secret mechanism touted on the new Frex SimWheel (whole thing just looks like it's giant traction motor to me?).
Very temped to buy one but at £800 plus shipping etc it better be pretty spectacular!

Anyone have any insight it to what it is... I noticed ShigeT mentions it's patented worldwide but I can't find any reference on any online patent search.


Matt

It looks like a big screwdriver motor, with planetary reduction box to me!!! LOL



Thanos

LOL, you might not be far wrong.
On the jp patent office search I found something about a backlash free planetary gear system.

Not patented by frex mind you. Although maybe shige is just using something off the shelf, that fits the pattern of their other products I suppose.

Btw, I've been working on scaling up my own DC gearhead motion base to full size for a while- nearly there so should have some posts soon. 1 axis is proof of concept is working. Soon as I hook ip my other motor I'll take some pics.

Matt

Or a rolling shutter motor ;D

Regards
Christian

people are getting their frex wheels over at rsc they're posting, nobody's yet to give a review but there are a couple pics up.
you guys have any idea as to what this is made from? do you guys think it would be possible to make our own ffb wheels using x-sim? it'd be nice to try and get a frex type wheel too :thbup: maybe i'm being too greedy :tape:

The motor is way smaller than I thought.
Obviously it is the smallest part in the whole construction.
But let us discuss of what the hidden mechanism below the cover may consist of.
There is a gearing for sure, but the major part seems to be a kind of lead screw mechanism.
Such a lead screw drive could easily restrict the wheel rotation to a defined degree limit, and it would be way more rigid than all those toy wheels currently available. As well the the positioning feedback unit is perhaps connected to the lead screw, and does make a linear movement, instead of using mulitturn pots.
Perhaps there is a magnet mounted on the lead screw, and a hall-sensor detects its position then.

Btw, unlike ballscrew drives, which are very expensive, leadscrew nuts including spindles are available for very little money at ebay for example.

And why not trying out a DC screwdriver motor including gearing ;D

Regards
Christian

Hi
I think you can find most of the parts under the carbon cover ,cheap on Banebots.com
regards Ad

From wiki: Due to their low internal friction, ball screws can be back-driven (depending upon their lead angle)

Perhaps with 4 starts threads...



Thanos

Hi
Dont forget when you want to work with screw and nut ,You must have a big pitch because
when you come to the end with a little speed (with smal pitch) the nuth will secure it self on the bearingblock(end block)
and you need a hamer to get your steer lose.
regards Ad

Well they write on their page : Optical encoder for precision and years of use for wheel axis. so thats it
How they have 1080° stop i am courious to, ledscrew is good idea in picture its even simplier version. They dont say that you can adjust it.
If you lisen to el. screwdriver its even worse than DFP so thats bad idea :no:

EDIT: Best way to go is lbodnar way: BIG AC servomotor no gears only optical encoder. Its fast, powerfull, silent, but also not chep (FREX to .. )

These are words from Shige himself:

That will not used a Gear nor Belt.
I faced limitation of the gear and belt because of their backlash, noise, loose, energy loss, too much complicated...... I knew that is not a suitable mechanism even if we tried most expensive planetary gears.

Mysterious?
Yes, the company also supprised the usage of the mechanism never used like that he said in spite of who is a industrial leader of Factory Automation

I confirmed this is a innovation design and aware necessity of take Patent because we confirmed it is only a mechanism that can realize real car wheel feeling that is not available so far. No backlash, No grindy feel, quiet, multi turn, mechanically adjustable lock to lock, hi efficiency, can install upside down for formula type tub, slim shape .....

You can not turn in corner with 25cm Wheel with 100% power setting.

We couldn't get good price depend on our previous design which needed to use expensive unit inside.
So we had started redesign the internal mechanism built into plate and frames of the wheel unit has same mechanism by each functional parts built together.
Functionally, out looking are same nothing has changed.
We will start test on the new one very soon.
The new mechanism let get the price down a lot.
But still many expensive parts we have to use into the unit to realize the real steering feel but getting closer to the price for the market not only for a enthusiast or research laboratory.

I am glad that I could invent and bring on this mechanism(EU,US.JP Patent.P) has No backlash, No grindy feel, Low mechanical drag, Stronger and faster force feedback which you can feel a tyre in game is made by rubber like a real car.

If that is about power transmition from motor to wheel i am more curious . If they dont use belt or gear there are only a few things left. They could tramsmit power by hydraulic. Then i get idea what if they use something like magnetic mechanism witch is used in old car instruments (magnet rotating in cup) but in bigger version

When I first saw the shape of the packaging a long time ago I though there was some kind of linear motion inside ( an SCN5 ;-) ). But then as time went on I though it was just a massive motor 1:1 with the wheel... thats obviously not the case from those pictures.

But how would you convert the linear motion of a lead screw into rotational motion perpendicular to the shaft for the wheel motion? Some kind of splined drive at the end?

The motor from those pictures looks tiny I would assume the linear element cannot be back-driven so there is no need for powerful holding force. In which case there must be a torque sensor on the wheel itself to allow it to be turned by energizing the motor?

I wish we could find the patent!


Matt

There would be no need to do that.
The leadscrew would restrict the movements on hardware side when reaching endpositions/endstops, and would carry the moving part of the position tracker in a linear movement.

The spindle would transmit the rotational power directly to the wheel.

But seeing this tiny motor on the pic, I hardly can imagine that it could drive the wheel directly without gearing. Turning a 30cm wheel connected to a spindle that fast and powerfull, requires alot of torque...

:?

Regards
Christian

I agree with Christian... but as far I can tell from the photos, the motor is not aligned with the leadscrew... its placed a little lower that means it must be somehow geared to it...

I'm looking for the patent for over 2 hours now with several combinations of words, but nothing... :thbd:

Perhaps if a simwheel owner could remove the lid and show was whats inside... :adore:

Regards, Thanos

How about NCG gearing???

http://en.wikipedia.org/wiki/Non-circular_gear

Its more quiet than normal gearing! And I have heard the simwheel making some noise, when turning too, on a comparison between a G25 video about its noise level!!!!

What about friction gears? They suffer from slip, but if connected to a postion tracking system, this does not matter.

friction gears transmit direct, smooth, less noise, and backlashfree.
And of course the transmission ratio can be set as like with gears.

Regards
Christian

EDIT: friction gears, not roller drives

it takes 1,5 jear for a patent to go public the normal way ,and 0,5 jear for the fast way but is than legal for 5 jears no 20 jears
i think you are looking in the patent blackhole
regards ad

friction gear example:

The JP patent office shows the detail of some patents from 2008, Frex's was made quite a while ago as the wheel has taken ages to come to market.

An automotive company called NSK Ltd has man patents around steering mechanisms.
However ShigeT mentioned it was a company for factory automation I believe.

If someone could whip the lid off all would be revealed!
Maybe we could just ask Shige? If its patented he has nothing to hide... we can bask in his genius ;-)

Would you really put a huge lead screw into it just to set the endpoints? Seems like it would be doing more than that, the motor must be geared to it.


Matt