DIY Linear Actuator design

Hi Guys More Video's welding leaves a crap loads to be desired hold my hands up to that but we will see how it holds up , as per some more great advice from @SeatTime i will have a support frame just under the unit to s=catch me or the they dont know it yet crash test dummy room still to be cleared but as this is test mode i'll live with it for now Power supplies are currently 2 x 12volts x 50amps output each server PSU's arranged in parallel so im thinking a good 100Amps capability because all motors share the supply and so far max peak at Amp meter seems to be circa 40-50 amps with the platform chucking itself all over the place ....load testing today though so fingers crossed ------Now to find the crash test dummy i mentioned

Love it @wannabeaflyer2 .

Get on the dam thing and stop messing around

My frame under the rig also acts as a enclosure to hold/protect all my electronics Ie. computer/powersupplies/drivers etc and has an integrated step to make it easier to get into and out of the rig. Also agree with @silent Chill, unless you have something more to redesign or fix - time to saddle up - no guts no glory . As for power supplies I am using 6 x 12v/40amp Led driver power supplies - so 240amp max in total. When doing testing I was seeing current usage of up to 20 amps per motor on my amp meter at full tested load - so possible 120 amps total for the rig motors not including any possible spikes that were not captured by the meter.

Cheers @SeatTime ..LOL @SilentChill yeah I know your right but I could not get her to sit in the dam thing LOL ( Women eh , go figure ) , so guess I'm gonna be my own crash test dummy ... Soon Guys Very Soon

For @SilentChill just for you sir Bums on seat as they say .. took a risk as i did not have the crash frame fitted under the platform yet need to buy some more wood or get adventurous with Welder again LOL,


so here goes this is my first proper sit and ride , i have a better video but why oh why does Youtube take 20 hours to upload 7 minute clip :-
Observations :-
one actuator motor seems slower that it should be ...may need to check the sabertooth settings or change the motor ( luckily i have 2 spares ...
The new Welded Frame make the top platform ohhhh soooo much more stable (even with my very amature attempts at welding) actuators now rock solid and stable even without power Yeeeeeessssss


Power supply did not trip out during the rapid movement load testing in the 10 Minute video so not sure whats going on there. but hey i will take it as a good thing need to now uprate my Power sully leads as the temporary ones were just that to prove the system works but i suspect they are causing some Volt drop due to being wrong gauge

Finaly download asseta corsa and Project cars So they are next test configurations to be tried ..
need to ask you guys about top platform to Bottom platform size and the effect on the angles achieved by the platform ..

Techi Question i need some feedback on :
Does a Smaller Top platform in relation to the Bottom mean the operating platform angles are greater or less ie. 700 circle Radius on top platform with say 850 on base give greater angles of operation than say 850 on top with 700 on bottom ..

in these videos the travel limits and speed are reduced as im still learning about fine tuning the software and some elements of the AMC128USB controller .
Sorry for long post but you guys Know me by now

Haha @wannabeaflyer2 great stuff see it wasn't all that bad cant wait to see it at full steam !!

I got a few questions for you if ya got time

How far does the ball screw travel after hitting the limit switches ?

And have you a picture of how you connected the UV to the bottom plate of the actuator and to the base ?

Cheers matey, keep up the good work

Hi @SilentChill feel free anytime to ask questions good buddy you gays set the standard and we all learn something ..
with regards to the ballscrew overrun after tripping limits switch I would say a good 40mm due to I guess inertia .. this does eat into the total travel a bit but so far i'd rather save the mechanics than gain an inch or tow ( dont tell the missus that I said that LOL ) i'll try to get some pictures posted later , one thing I did do was get limit switches with extended leavers ( 40 mm I believe ) the reason was due to said overrun ...to prevent the system becoming active again once it passed over the limit switch.. I also extended the Contact face of the switch activator with the though that once the switch was tripped then it would be mechanically held open until in my case the Actuator motor was reversed manually past the trip point as it were ..

the only down side of that is that once tripped I have to find which actuator was affected and manually rotate it back to before the limit switch ( note I press my E-stop butt to ensure the motor is not active, or it would go to the demanded position as soon as the limit switch was reset ( def not good with finger in the area )

Now need figure a way of electrically backing the Motor up to reset limit switch without getting out of sim ... all part of the learning curve and I'm loving it ..

@wannabeaflyer2 "you gays set the standard " bahahaha

Thanks dude !!

I was thinking to be risky and just put the limit switch on a bracket that's tight but not too tight so if it does hit it, it moves the bracket a little but because its tight but not too tight it will act like a bit of dampening so it doesn't overrun as far. I will try and see what happens, hopefully there will be no over runs to try it haha

I'm just on with getting the belt drive in place for the pot and then I should have a 1st prototype to test

Hi @SilentChill here is the detail of my current limit switch setup ... at some point soon i'll release the final drawing package for the whole sim including actuators .....its running at 16 pages at the moment lol but think there will be good info in there for the guys to use or modify .. Have a look see good buddy and pick the bones from it I always say there are many ways to skin the proverbial, so feel free to skin away mate

For Silent chill a little late now But like i said many ways to skin a puddy tat love you method so me thinks update will be required by me soon, You may notice the retaining clamp over the pot . i found the chepo pots would begin to seperate if the belt was tensioned too much , so they were a belt and braces fix which did the job nicely ... once again pics for info

Thanks dude for the pics, but could you do pictures of your UV Mount !!!!

Hi @SilentChill do you still need pics of the UJ setup ? will stick a few on if thats still the case ,

Well i have had been trying to get some full on testing of the sim and Project cars ,,,Hmmmm after numerous wall and hitting everything except the tarmac i have come to the conclusion the sim is fine its the damm driver that needs debugging LOL

General shout out for help guys regarding setting my GT27 Force feedback wheel , im gonna say its t0o sensetive and driver oversteers like mad ( or in truth Driver is ham fisted ) trying to drive in any sort of manner seems crazy , and thats with the sim switched off as well , im pretty sure the motion cues are good for this stage but im finding it tough to get some track miles .. Looked at the GT27 Forum and will try some of there tips , but had to ask you guys here if anyone has some basic setting parameter i can try for starters , Steering deadband , Steering sensitivity, not stressing about the force feedback yet ( that may be part of the problem though ) so just any screen shots of Project cars Control pages for me to compare would be great , Have my ( im calling it Betty 6dof sim Cant drive comes to mind

Cheers Crew

PS @SeatTime info request Could you send me a copy of your slow cars .BFF file for me to compare with my attempts at setting the rig , i know each sim is mechanically different and the info cant be used on mine but project cars and asseta are new to me so would be great to compare working files to those i have been using now Thanks

Yes please if you would

Is it not the rotation on ya wheel ? Should be at least 540 degrees for anything half decent imo

id ditch project cars for testing and use assetto personally.

the out of the box force feedback in aessetto is like night and day compared to pcars, it just works. the fidelity of the laser scanned tracks also wins over pcars IMHO.

Hi @paulg100 cant seem to get Asseto working at the moment sure its just a setting up issue ,so loo forward to trying that option . cheers for the tip

Hi Guys Minor update, Sim seems to be running quite well but not had a chance to do much duration testing due to my keep Crashing the dam car on the other hand it seems my GT25 force feedback wheel doesnt force feedback WTF ( I Know shades of bad workman blaming tools ) but I may have a problem, ( was an Ebay purchase that I have had for years but in storage) any ways trying to get a test program to check out the operation , most features seem to work but noticed Clutch does not get detected and H shifter does not go into sequential mode , so may require a stripdown ( Bummer)

Hey guys can anybody point me to a Simple DIY Button Box for my sim or know of any reliable sim dash android apps that they are happy with ?

Cheers Crew

I used one of these in my virtual pinball cab.

http://groovygamegear.com/webstore/index.php?main_page=product_info&products_id=239

can connect 32 buttons/switches to it and map to key presses with the included software. can make a great button box with it.

Take apart an old keyboard lying around and you have a button box with almost 100 buttons

Hi guys mini update my system just had hour of running and took a battering but held up well , just thought I give you the heads up for lessons learnt,
Actuators seem more than man enough to chuck me around nicely
double check the coupler screws to make sure they are well secured against motor and actuator shafts .
Check for Belt alignment ref POT gearing
Be aware that too much belt tension can damage the pot .
Under extreme .
Limit switches should be mounted so that even if the actuator overruns it will remain triggered .
KEEP FINGERS AWAY from pinch points when actuators are powered ( they move bloody quickly )
Limit actuator travel during initial testing to minimise mechanical clash in the event of and issue..
on a less doom monger note ... your gnona be well pleased when these babies lift you for the 1st time . lol
oh oh and the current consumption according to my in line amp meter blips at 75 - 90 amps for all 6 motors combined is when the unit is motoring along with my 95Kgs of lard sitting in the seat and add another 25 for seat frame and perihperals ish .. so dependant on the shared actuator load it seems the rig is maxing and circa 15 -25 amps per motor only for momentary peaks ..
My 2 x 32's sabertooths are not even warm and the motor casing does not seem much above ambient no heat per say form the cables and the only annoying thing bearing in mind im deaf, is the fan noise LOL .. now got any forced cooling fitted yet but things looking good even at this stage .. will copy this to my post but just wanted to pass on my short term observations ref my project ... Video coming guys pre warning all drivers aids used LOL I know no shame

Hi great build so far. I have been following your build and being a machinist have a handle on all of your mechanical parts but if you could post a parts list of all the electrical items you are using and a wiring schematic that would help me get my head around that part of your build that would be great.
Thanks.