Low cost 2DOF/3DOF/6DOF motion simulator - DOF REALITY

Thanks for the reply noorbeast. So you could get away with one person holding the rig to balance? I could possibly put my girlfriend in it and add another 20kg in weight - not sure she would appreciate the idea

What you are trying to get is the rig sat above the universal joint. If its correctly balanced, with you sat in the rig, you should be able to rock left to right and front to back.

If the rig isn't balanced then it will be a lot harder to rock forward to back or left to right. So the easier it is to rock, the closer you will be to the rig being balanced.

Sorry, I'm not explaining it very well.

Andy

The problem is, when you disconnect the two control arms, if the rig is unbalanced it will fall quite easily.

As Noorbeast suggests, invite a couple of friends round and offer them a race night in exchange for a little help up front.

It only takes an hour assuming you are not too far out balance wise.

But the important thing is the balance is with you sat in the rig.

As I said, I can sit in the rig and rock front to back and side to side with very little effort. Just a slight shift in weight.

Thanks guys, I’ll see how I go. The rig rocking makes sense.
The 6 dof looks interesting...

Edit: thanks dofreality for your post as well.

disconnect both front motors arms.
Be careful not to fell off the platform and heart yourself, move very gently.
Slowly get it to the seat by sliding your body in to the seat from front to back
and checking the balance on the way. your goal is to find the point of the front to back equilibrium (platform is not leaning to the front when your legs are at the pedals plate) and not to bend the seat to the back. if this point is some way before you properly completely slide in . you need to stop moving and move your seat to the front a bit and repeat this until the equilibrium will be around your normal seating position.
If you slide all the way in and still not reached equilibrium (platform is still leaning to the front when your legs are at the pedals plate) you need to move the seat a bit to the back and check again.
When done you can do the same for the left to right balance. Again if you are doing it without help be very careful.

I am interested in this answer too because I will have the same problem since I do not have 2 people to help me to calibrate the p3

Again, I agree with Noorbeast, please be careful when adjusting the balance points for your rig.

It really doesn't take a lot for things to get out of hand and people or equipment get broken. I have on a number of occasions disconnected both motor control arms and the whole moving frame smashing over one way or the other. Luckily I didnt get hurt and nothing got broken but it was a little scary.

If you really cannot have a couple of people come and help you then the only thing you can do is adjust in small incremental steps.

1. Sit in your rig and move your weight around. Find out where the rig tends to fall. For example, if I sit in my rig, it takes a lot of effort for the seat to rock over to the right. That means weight is on the left.
2. Unbolt your seat and move the seat into the next mounting holes in the seat frame.
3. Go back to step 1 and try again. Has it made any difference, does it feel easier to rock to the right?

I slotted my seat frame so it allowed me the ability to slide the seat left to right but that wasn't enough for me and I also had to re-position my pedals and my wheel motor to the right as well.

I was now able to sit in the seat and gently rock side to side pretty evenly.

4. Now go through the same process rocking forward to back. If you have a reclining seat and seat sliders then finding a forward to back balance a little easier without having to disconnect stuff.

You will also notice there are fore/aft positioning of the universal joint where it mounts to the spine of the rig. All of this gives quite a lot of fore/aft adjustment and you should find a balance position quite easily. All of this can be done without disconnection the motor arms. But it is still easier if you can find people to help.

5. Once you have the rig balanced as best you can, then adjust fore/aft one more time to put just a little bit of weight forward (and it really is just a little bit of weight forward). This helps take out some of the slop in the worm drives.

6. Now install and run SMC3 software. Sit in your rig with SMC3 driving a motor (I find the motor following a sine wave works best) and view the various traces to see if the motor output is able to follow the sim demand. If the rig is balanced, you should see the motor output trace (the green line I think) follow the demand line (blue line I think, but I have not used SMC3 for a while so could have the colours mixed up).

The SMC3 software allows you to see what your rig is doing. Get the rig balanced and the demand and output lines shown in SMC3 will follow each other. Get the balance wrong and the lines wont follow and you are likely to see all sorts of weird stuff.

Sorry, I know I'm not explaining it well and it does take a little time to understand what is happening and what the SMC3 software is telling you, but it is actually straight forward. Probably easier to understand that explain.

Thank you all for the replies for the balancing!

I wish there would be a video tutorial for the balancing. That would help a lot!

I am so curious to see the final version of the 6 dof and after that, of course , try it, since I ordered it

I don't think you will have the balancing problems of a 6 Dof rig.

Lots of other problems I'm sure, but balance probably won't be one of them.

What other problems ? Lol
Should I be scared ? Lol

I don't know Marco, but we are all going to sit here and follow your voyage of discovery.



Andy

Haha!! oh man! I think we will share that journey together lol , because you will be of great help during the setup and tests and for sure we together will get to see and know about the 6dof experience

When are you expecting it to arrive?

Andy your explanations make sense, everyone has been very helpful. Thank you to all of you.

Depends on the size.. I do balance my 6DOF, to keep the load similar over the three attachment points (six motors) for best performance. My front two attachment points are adjustable to enable this especially if you add things like heavy DD Steering Servos or pedal boxes. I used three scales with myself and all equipment fitted into the rig and a second person recording the readings , similar to how you would 'corner weight' a race car.

Where can I get information on the 6DOF upgrade/sim from DOFReality? I went to their sight but found no detailed information on the 6DOF.

Danny