Rotary dampers; looking for cheap ones for use in race wheel

niels007 · Post by **niels007** » Fri Feb 23, 2007 5:49 pm

Hey guys,

Where would the world be without 'off topic' sections in your favorite forum..

I'm hoping to build a better steeringwheel for use in race simulations. Now I hear you all think "Force Feedback!" which indeed would be great, but doing that properly quickly reveals a lot of downsides and considerable costs.

So for now its maximizing the feeling of wheel resistance without using "FF". A spring + damper arrangement makes a lot of sense. Springs are easy to find, and quite affordable. Rotary dampers on the other hand tend to be 'high quality industrual devices' with impressive price tags. This one is ideal, if only it cost less than the ~220 euro they quoted me: http://www.kinetrol.com/dampers/D-S.htm

Since the 'load' is pretty low, I'd only need between 0.2 and 0.3 Nm/rad/s for which their cheaper ~100 euro damper is not suitable.

Does there happen to be anyone here at SPCR involved with such devices? Compared to linear motion dampers, rotary ones seem to be sparse on the market!

/Niels

PS: this is currently a wheel using a rotary damper:
http://ecci6000.com/6000_wheel_01.htm

rbrodka · Post by **rbrodka** » Sun Feb 25, 2007 12:48 pm

I don't have a clue.

But I had a thought, could you use a rack and pinion arrangement to convert the rotary motion into linear motion, then use a linear damper? In an automobile, the steering wheel is connected to a rack and pinion. It is the linear motion of the rack that turns the wheels.

jhhoffma · Post by **jhhoffma** » Mon Feb 26, 2007 6:04 am

rbrodka wrote:In an automobile, the steering wheel is connected to a rack and pinion. It is the linear motion of the rack that turns the wheels.

Unless it's a recirculating ball system...like Mercedes used to use.

niels007 · Post by **niels007** » Mon Feb 26, 2007 6:09 am

Hi,

Thanks for the idea(s).. Technically possible but most linear dampers I found have a little deadzone when changing direction. It might also be tricky to DIY the rack/pinion cheaply..

Seems I will have to shell out for the Kinetrol damper eventually

disphenoidal · Post by **disphenoidal** » Mon Feb 26, 2007 12:25 pm

What about a connecting rod/wrist pin arrangement, like what connects the crankshaft to the pistons in a car engine? That would allow you to convert rotary to linear motion instead of a rack and pinion.

jaganath · Post by **jaganath** » Mon Feb 26, 2007 12:48 pm

jhhoffma wrote:
Unless it's a recirculating ball system...like Mercedes used to use.

How did this work, out of curiosity?

jhhoffma · Post by **jhhoffma** » Tue Feb 27, 2007 8:17 am

Basically, the steering shaft was a screw (or worm gear) with a sleeve (ball-nut rack) that glides up and down over it. The screw moves ball-bearings in a spiral path around it (the bearings are in a closed loop and "recirculate" over and over, hence the name). The bearings move the sleeve up and down which moves the sector gear, which is attached to a Pittman arm which connects to the track rod and then to the tie rods and steering arms.

Like this:

And this: