6dof motion platform ‘lite’

Motors ordered
http://www.aliexpress.com/item/Golf...-with-CE-12VDC-150W-ratio-26-1/293841828.html

I want this!
http://www.roadtovr.com/hands-on-oculus-rift-crescent-bay-prototype/

already? are they trying to keep up with Apple or something with updated equipment?

That's absolutely fine by me we're not getting any younger and I'd much prefer to see better vr now than in 2-5 years...
The only problem is that there is no order button

Hi @eaorobbie

Thank you for your reply.

I've been thinking about lever sizes recently, and I wanted to check if you (and others) if it's a good idea to increase the lever length further and reduce RPM at the same time with a higher ratio sprocket system?

3:1 sprocket ratio:
7.5cm lever with 40 RPM would result in about 0.31416 m/s or 31cm/sec motion speed
4:1 sprocket ratio:
10cm lever with 30 RPM (4 to 1 sprocket ratio) would result in 0.31416 m/s or 31cm/sec motion speed.

I've calculated motion speed from this site:
http://www.endmemo.com/physics/rpmlinear.php
does this look correct to you?
With lower RPM, the torque would be increased (4x14 = 56Nm) so it should be fine with the longer lever, and as a result of the longer lever I would get more motion out of the platform (with 10 cm leaver, compared to 7.5 cm lever) at the same speed?!

Is my thinking correct or have I missed something obvious ?
Will I loose any other motion with lower RPM?

Thanks,
Tino.

Hi,
you have the 6-DOF firmware for Arduino? Because it can not find anywhere.

Your idea of gearing down will work. I would be still trying to keep the rpm above 50rpm or you may as well use wipers , same speed.

But lowering the rpm will result in a sim only suited to flight simming where the motion is quiet slow and cumbersome , most 240v sims popping out of the wood work are like this, there is no fine strong quick vibrations present in their motion and any real quick flicks of impact, may as well be on an Arcade machine.

But seems to be the norm for 6DOF units except for the real big industrial hydraulic units most motor driven are very slow in movements.

I have been on the 6DOF CKAS unit and it was a laugh, but due to their software, missing cues all over the place , see the dip in the road, wait for it, wait for it, ah there its is after Im 20m down the road, spent 10mins on this and got off shaking my head and was ushered out of the shop before I could comment about it. In the end unit got sent back, no buyers. lol.

Lever speed calc is done a little different not just a straight conversion. We talk the linear movement like mine is 80mm but lever actually travels nearly 120mm in curve but the total linear movement from Min to Max is what is felt on the seat of 80mm.

Hi @eaorobbie,
Thanks for your reply.

I had a look at ckas simulator, and the W3s does seem to be a bit slow :
Displacement , Velocity , Accel
50mm , ±100mm/S , ±0.3G
http://www.ckas.com.au/6dof_low_cost_systems_62.html

Would 30 rpm simulator with 20 cm lever still be to slow?
if this calculator is correct that should result in 0.62832m/sec or 62.8cm/sec!

8cm lever spinning at 60 rpm procedures speed of 0.502656m/sec or 50cm/sec

I'm wondering if there is a minimum speed in cm/sec for a good racing simulator, or do you need high rpm (50 RPMor more) for quick changes in direction or bumps?

Do you think this simulator is fast enough?
I think it's 16cm lever, 20RPM = about 33 cm/ sec motion speed.


Regards,
Tino.

Hi all,

Just a quick update, I have received my motors and pololu controllers should be arriving today
However, after all the insults I've received from @bsft I will no longer update my thread on xsimulator.net and you can watch the progress of my build on Thanos forum.

I wish you all the best with your simulators.
Best regards,
Tino.

any updates?

@dave w , you will need to go to the thanos thread he linked to see his project.

@bsft, didn't see the link after the photo, not really interested in following it now that I know he's a sour puss

I could not find a project on the linked Thanos site from Tino. Only big dollar AC simulators.

Thats what Thanos is pushing, big dollar 240v sims. Even though Tino is looking at 12v motors, I suspect its only because there have been 2 12v 6 DOF sims pop up over the last year or so, proving you do not need 240v motors to have a 6 DOF.
His comments about our seat shakers is an insult to 90% of people on this forum. We build what we like and thats that. If we want a "shaking" seat, we can. If we DO NOT want a big dollar 6 DOF, thats our choice. Your progress is showing it can be done with a decent budget.
Historiker was building a 6 DOffer, but has stalled due to moving into his house. Give him time or just send him a question.
I am sure your actuators will do the job, considering there has been posted (somewhere) a BFF 12v actuator 6 DOF sim video.
Cheers, David.

Just wondered if Tino progressed anywhere with his design. I have no issues with the big AC 6DOF guys, would love to do the same, but cannot justify the expense. I have done some real world testing on my actuators, so am about as confident as you could be that they will do the job. Currently building my sim frame. From what I have built so far (all aluminium) it should come in at around 5Kg. I will also be using an alloy integrated seat, keeping the CG reasonably low. Low inertia = performance.

Hi Ale
I'm really desperate for Arduino 6 DOF firmware for SimTools and maybe Ian's cue software. I can't really afford Thanos' gift to sim makers, and even though I know it's the best thing around, everything I have done with the Arduino, even high speed stuff, has worked really well, so I really want to try 6DOF on Arduinos. Did you ever get it working?
Cheers
Ed

Thanks, mate. BTW, I'm also in Au (Central Vic). I'll PM eaorbbie if Ale doesn't respond. I'm fairly sure from what I have read that Ale has already done it. And Ale could cut that code in his sleep. He is a genius.
Cheers
Ed

Hi @Tino

I have questions.

Before making 6 dof simulator like stewart platform, should I have to learn stewart platform kinematics?

How does it work between simtools(SW) and simulator(HW)?

I would expect you to kindly explain because I am a newbie.

Thanks in advance.