DIY 2DOF Budget Build

Most of the problem was my own doing, centered on my motor location.
So when it went over center the rig jammed hard on the motor mount, plus the gears do cop a bashing with their inherent backlash and the quick reversing of rotation
just takes it toll on the bronze spur gear.
I can't remember if the teeth on the spur gear are straight or angled which would determine how you might rotate or reverse the gear to use the undamaged section or you might have to cut a new keyway
on the shaft or gear which is doable as I have a lathe and mill.
The more heavy duty gearboxes are about $120 AUD each, which is about $1.50 USD and worth doing if it lives longer.
I extended the motor output lever to clear the bottom base frame but it still jammed nose down and over to one side which is why it bottomed out on the mount.
remember this was designed on the fly and revisions were decided on during sleep. So no CAD involved or 3D modelling.

Ahhhh yes, that's right, yours is a full-frame mover.

I forgot about the nose bottoming out onto the floor if you were to go past center or have a runaway motor.


Mine's just a simple 2dof seat-mover style, which if such a situation were to arise it'd just break a pot and/or feel like I was sitting on a bucking Bronco until I hit the emergency shutdown switch.


I guess you could eliminate your issue if you were to put the entire rig onto a riser, or weld on some legs with enough floor clearance.


How are you enjoying the SimTools programming/tweaking aspect?

If you are experiencing jerky or distractive motion, the smoothing option for each axis works wonders if used sparingly.

I ran into a jerky situation on one side and software smoothing didn't help, but it just ended up being a defective/worn out pot.

5 minutes after popping on a spare I was back it business.

Things like that make these DIY rigs vastly superior for users like us to troubleshoot vs a commercial kit or finished unit with "mystery" parts.


Good luck!

To gain enough clearance for over rotation events I would need to raise the top frame by about 50mm or so which would make it a lot more unstable with a higher COG.
Sim tools is still giving me grief which is part of the learning curve and it seems every sim's sweet spot is totally different to another.
I have been trying to get Project Cars setup and have gone from bad to worse and back again, so I disabled everything except Roll but it still make odd moves like diving forward when at top speed on a straight or the opposite of pitching up dramatically when trying to ascend the fast uphill section of the Bathurst track called the cutting , .and it totally buggers up your line and concentration.
And before you ask, yes I tried your settings that you gave me without much luck. I have also tried the Smoothing setting , also with not much luck.
I have tried dumbing down all of the settings and it still can be pretty aggressive in it's motions which is probably where I am going wrong by changing too many settings at one time, which is something you never do in a real race car situation.
I'm not that concerned as the longer it takes to beat the beast, the longer that I keep it as usually once I do a project it's out the door and on to the next new idea, speaking of which I still have an off road buggy that is 98% complete and needs some time spent on soon after I abandoned that project for a year when Mr. C entered my life and took all of my time and energy to overcome.
Who knew retirement would be so busy

Oh, well then that may be part of the problem then.
ROLL is geared more towards flight sims, and you only need a small amount on a racing sim in order to simulate front end dip/dive to either L or R side, such as driving into a corner.
If you were only using roll then pCARS would probably not feel right at all.


There are three rotational degrees of freedom (roll, pitch, yaw) and three translational or linear degrees of freedom (surge, heave, sway).


The main ones for racing sims would be the translational ones:
SURGE for acceleration (rear dive) & braking (front dive).
HEAVE for road bumps/kerbs/textures/etc.
SWAY for opposing side to side movements

PITCH works great for elevation changes (Brands Hatch, Spa, Nords, Monza, etc.)

ROLL, small amount just to simulate front L & R dive when driving into corners.


I'd just start with surge, then move onto sway, heave + any others you wish to use.

Even with only 2dof you can dial in the "Extra 1" setting which can simulate traction loss to some degree.

Take this all with a grain of salt, as I'm just learning as well.

I installed the new gearbox and replaced my rubber fuel hose connectors between the pots and the motors with some proper ally flexible anti backlash connectors
which seems to have fixed most of my problems, touch wood.
So here is my first video of it actually in motion in Dirt 4

Your probably right. I will set it to the right direction.
I did have a small issue when I finished a stage of Dirt 4 the rig is sitting there and both motors are making a jittery type motion so I added some smoothing which I think ha s sorted that out
but I was not sure if it might be related to my settings in SMC3 which I played with and increased some values then lowered them until any jitteryness went away.
Any ideas ?

I reversed the Sway direction and it feels correct I think, but I'm too busy trying to keep off the snow banks

Today here in Australia we have Anzac Day to commemorate and remember all service personnel who have served in all theatre's of war in the last century
and to those who made the ultimate sacrifice and never made home to the country and families that they left to defend for our freedoms that we cherish.

They shall not grow old, as we that are left grow old.
Age shall not weary them, nor the years condemn.
At the going down of the sun, and in the morning, we will remember them.
Lest we forget.

In the US we have two different holidays. Veterans Day celebrates the service of all U.S. military veterans while Memorial Day honors those who paid the ultimate price while in military service.

Hello,I know this is probably a stupid question but why did you angle your seat?

It was basically how it ended up.
I didn't like the seating position with the seat runners level so I reclined the seat a few degrees to find the sweet spot and mage the brackets to suit.
That's the difference between shop bought and custom made.
You get to chose what you the builder wants.
Easy.

Oh okay,thought it was to balance the the lever movement.Thanks for your reply.

It was all made adjustable.
The rail mounts had three different hole sets so it could be adjusted for and aft about 25 mm.
and the CV joint also had three sets of mounting holes which gave another 30 mm. of adjustment to fine tune the weight/balance point.

Hey mate.

Nice work on finally getting it all sorted, looks like it’s running great now!

I’m about to weld up my frame and make the motor mounts..... and being in Brissie, I’ll be ordering from MotionDynamics also.

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

I have a question though.

The motors don’t come with a keyed shaft, just a hole to put a shaft in....... though you can add a blank 12mm one as an additional extra.

Can you talk me through what you did to make your shaft, so you could connect your levers?

Thanks!

It's been a while but when I ordered my motors I opted for 50:1 gearboxes and from memory they did have a keyway cut I think or I may have cut it myself on my mill
I know that I used some heavy wall tube and drilled and tapped those holes for lock screws, one of which registered on the keyway and the other for extra security.
Then of course those were welded to my levers which started out at about 100mm. long with multiple mount holes spaced along the length, but I ended up cutting them down
to about 75 mm. as that had ample power.
You just have to think about your next moves when building it and CAD is fine for theorizing something but doing it in real life usually presents you with all the hidden little faults
that the computer model might not show which is no different to a set of old school blue print drawings.