Showroom TecSim - 3DOF with traction loss

Back in 2009/2010 I built my first Sim; A 2DOF joyrider! I had a lot of fun building and using the simulator but now I feel it is time for a change.

So after 3 years of not visiting the site I am back! A lot has changed since I last visiting; new website, new software and all sorts of new electronics.

I tend to mostly play driving sims so wanted to have a go at building a seat mover style sim. Also I feel traction loss is a must.

For the motor controllers I have decided on using JRK12v12's. Although quite pricey there wasn't anything else out there that could match the performance of the JRK. I'm also planning on getting a 1080p projector and having a go at a superFOV setup!


Progress so far:
I've connected up 1 of the JRK's to a motor and had a play with the config utility. For feedback I'm using 180degree hall sensor pots. These seem to work great and are perfectly paired with the JRK as they have a 12bit output. Also are non contact so should last a lot longer than a conventional pot.

I'll try and keep this thread updated as things progress!

looks good.

Hi @SimonUK.
Welcome back, I've built a 2DOF platform mover for driving and flying sims. I've also used JRK's with 180 degree Hall effect Pots as a replacement for standard Pots which were wearing out too quickly. The Hall effects are very good and give very smooth motion.

Mike

@SimonUK could we please have some info on the hall sensor pots, tried making some but didnt like the results and ones locally from shop are nearly 80 bucks each.
Thanks.

These are the ones I am using: http://uk.farnell.com/jsp/search/productdetail.jsp?SKU=2319662

Not too expensive at £12.75 each.

They come in a variety of different angle options. I choose 180degress which is perfect for a seater mover with pot attached directly to the motor output. This ensures the full voltage range is used.

Also I recommended using 3 core shielded cable for the connection to the motor controller to keep noise down on the analogue signals. Also don't make this wire longer than is needed!

Thanks @SimonUK , I might try to find them here in Australia, cheer.
Worst case I will have me buddy fetch 2 and send them over in the post, maybe.
I would edit your first post, and place this info in there too, first time readers will see it first before reading on. Just a suggestion.
Plus you are spot one with the Jrk pot wiring I use old usb cable 4c only for convenience, and each Jrk lives next to the motors and pot so its all sort as possible, another tip is to have the motor leads as short as possible so to limit the amp draw in turn allowing the Jrk to push past its 30amp limits, with good cooling too.
Thanks again for the info on the Hall's. Bingo want two of them please sir !

A question for all you JRK experts...

How do I get the current plot to show more than +/-5000mA? My motor current spikes way more than this so shoots of the scale. The box won't let me type in anything higher!

Also what do people use for heatsinks? I've found some small ones that will fit but they are only 18mm tall. I know some people cut up CPU heatsinks. Can anyone link me to one that is suitable?

Yea its a bummer on the graph bit, doesnt go any higher than 5amp (5000mA) the Jrk was never intended to drive the size of the motors we use, originally designed for the BattleBot market(Nerds that love Destruction). Hence a lot of the information is about weaker motors and not the big worm gear units we use.
The driver is capable of 30amp peaks, yes way of the chart, and some of us push it way past that, 40-45amps.
With the graph , I normally only select the Input and Scaled Feedback and error for PID tuning.
And if I need to see how it is actually driving the motor, I include Duty Cycle and the Target Duty Cycle to see if the driver actually needs more power(Amps).

For heatsinks I have been using these small animals for a while now, but with a 120mm fan(12v) on top of each Jrk and mount my Jrks off the surface as the air gap underneath them helps them disipate heat quicker. Never had one shutdown yet because of heat and please dont touch them after a long run on the sim, they can get that hot it will burn your skin on touching, Done that it hurts. They are quite strong.
http://www.jaycar.com.au/productView.asp?ID=HH8580

Farnell australia is called element14 these days... the same part number is available here: http://au.element14.com/bi-technolo...ll-0-2v-20v-to-10v-pin/dp/2319662?Ntt=2319662

I used the 300deg pot from same place, delivered within 4 days. From memory there was about $9 delivery fee.

Hi RufuDufus!
Kind of a joke: element14 is Silicium in periodic table

Time for an update!

Seat has been attached to the universal joint. I've also mounted the motors. What do people thing of the motor positions? I've used a 50mm motor arm length.

Next step is to finish of the electronics box and start thinking about the drift axis!

A bit unusual motor position/rotation, haven't saw that kind of setup yet, but if it works fine, why not

angle looks good, a little narrow into the seat so you should get BIG sway, but nothing a profile fix will not sort. Motors in position like that should be fine, a different idea.

What do you mean by big sway? Should the motors be further apart from each other?

They are completely adjustable in all directions so I can quite easily change positions if required.

Let me explain
Example, my foot motor mount sim had motors 700mm from pivot and used about 70mm throw. Which gave me a surge angle of about 7 deg total, but because the motors were only spaced at 450mm, so its actually 225mm from pivot point of centre, the sway was 17 deg total. So with your sim, and I am usually wrong, because they connect a bit narrow at the shoulders, you may have more sway angle. But this doesnt matter, with my foot motor, I just turned down the sway force and number to make it better.
As said, I am probably wrong by only seeing a photo.
Dont worry, its a good job you are doing there.

It looks like it is, so just finish it, start to move and look if you like it. Then when youll have felt how it works you can try different placement of the motors. From pic it looks like youll have shorter movement of surge then sway, ofcourse as @bsft said you can sort it in profile. But you can make less movement in profiller, if it is too short then not much you can do there, motor position could help. Just finish it and try it
I have motors much closer and have to lower movement in profile as it is too much already for my likings, so in your situation no sense to make it closer right now if later you have to lower movement in profile, specially in your situation it is easily changeable later.

Btw can you tell more about motors you use, i see you got them long time ago, but maybe you still remember specs of them?

these ones http://www.motiondynamics.com.au/worm-drive-motor-12v-24v-200w-180-rpm-20nm-torque.html

Thanks for the feedback. I'll hopefully get it all powered up this weekend and then can see if anything needs tweaking. Having everything adjustable is a big advantage in my opinion.

The motors are from electric golf trollys. I got them from ebay but can't find they for sale anymore. They are 180W. Not quite the same as the ones bsft linked too. They worked very well for my last sim, so hopefully they will work well for this!

Ive had 180 watt versions of the ones above as well. Thats what the supplier had whenI first got a hold of them. 20 watts is bugger all.

Time for another update!

I've re-positioned the seat mover motors to be more inline with the seat. The previous 45 degree angle ended up with a lot of sway and not much surge! What do people think of the new position? Does it matter that they are mounted slightly higher up? They are currently slightly higher than the bottom of the seat. I couldn't decide if this will make the motors work harder or not!

Also the drift motor is mounted! Again what do you guys think of the position of that?

Today I have been playing around with a new toy. A Benq W1080ST projector 1080p and a very short throw lense. Am going to try and recreate a SuperFOV effect!