Showroom **RIP** - 6DOF project using 12v DC Motors, Sabertooth 2x60's (was MM's) and Arduinos + OSW

Yeah go on get outta my thread !!

By now you're probably received all the compliment.... Spend a few hours going through your entire thread.... I like your approached, just get it done and screw the math.

But I do have a dumb thought/question. It seem to be all of the 6DOF system I see out there are a bit over exaggerate the movement? No, I have never been in a real racing car going at 200mph, maybe that's how it behave. But by commonsense, most of the 6d0f seem to pitch up and down so much. I have drove a Nissan GTR, though with a lot of power, doesn't seem that much. But then again, I have never tried a 6d0f sim, so it may not feel as much as the video?

When you have the Rift on it does feel really good. I have less movement on this than on my 3DOF and this feels far far better.

How much movement you have now? Do you use all what motors give and could you tell example the dirt settings what motor use what force?

I have had to shorten my CTC to 50mm now ads my motors are over heating after prolonged use. So i need bigger motors i think but its still really good for racing.

This my latest video.

If you are brave enough try drilling/filing some holes in one end the case of the motors (making sure not to drill through the magnets) and on the far end of the motor (where the brushes sit drill some bigger holes and mount a fan to it. I have one motor that I accidentally burnt out, cleaned it up and got it working again but it would overheat after 10 mins of use. Since I've added the fan it stays cold. I'll take some pictures of what I've done to the motor. maybe by doing this you won't have to buy new motors.

I have put heatsinks on the brush ends also added fins to the motor body with 120mm fans top and bottom. It's the brushes which are over heating in turn making the entire coil overheat. Suppose that is why they are only rated at 14 amps. They are powerful enough to lift me and the rig with 150mm CTC levers but very quickly over heat

This is how to cool the brushes:



So not just adding a heat sink to the case of the motor but actually passing air through to the armature and brushes.
As you can see I've cut out holes where the motor case connects to the gearbox and placed the fan on the opposite side. What you can't see is that I have also drilled holes in the end plate allowing the fan to draw in cool air and blow out the hot air. I have also fashioned an air tight shroud so that the fan only draws air from the cutout holes.

Thanks @Alexey i will try and do something like that see what I can make up.my brushes do get very hot and there is no air circulation in the motor housing so this looks like a good mod

IMHO I do not agree - the motion is very reactive and the the motors seem to be strong enough to react in time. Save the money for a DD or something else

Interesting @Alexey

Similar situation to the Buhler Ekretz mod for the CSW but with using a Pump VS a Fan.

https://www.gtplanet.net/forum/thre...e-modders-thread-update-february-2014.274631/

How about wrapping copper pipe around the hot end of the motor and pumping cooled water through it like a CPU cooler.

I think that by only cooling the case you don't actually cool the brushes enough unless the brushes themselves are mounted directly to the case. The brushes in mine are mounted via a fiberglass board, so I had no choice but to get airflow over them. That pumping idea looks neat.

From my experience, wrapping motors with copper tubing and using water-cooling will extend the time needed before a cool down period is required. The problem with brushed DC motors though is that the armature, which is in the middle of the motor, is what gets hot first along with the brushes. So cooling on the outside of the motor is not that efficient since the heat must propagate into the outer casing first.

But while this helps somewhat to control the heating issue, it doesn’t do anything to address the issue of why so much heat is being generated in the first place. The only way to do that is to reduce the amperage the motors draw. If your case is like mine, if you don’t reduce the current, you will quickly burn thru motor brushes thus requiring replacement often.

What if you put every corner gas struts without damping to help lifting like this guy.

I have seen the video where he lift 180kg with those 4 wiper motor when he have 4 gas struts connected.
Look closely and you see how the struts move under the chair.

Dont make much of his slippers lol

Thats a good idea though, where can you find such a thing ??

@mrbeginner Ok found some on Ebay

http://www.ebay.co.uk/itm/550N-Gas-...4f69b87&pid=100005&rk=1&rkt=6&sd=301604231763

I will have to look into this as it could work really well with my setup and wouldn't take much to add them in the supports are already all there

Looking further into it and these look good from China http://www.aliexpress.com/item/Silv...tuds-Lift-Strut-Car-Gas-Spring/887549251.html

They aint MM's so they should be ok lol

you better check that those arent dambed version. I'm not sure but I think the tractor back window use right kind of strut. So you maybe can find them local spare part shop.