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[AldoZ]

Hello dudes.
After the great help of this forum, eaorobbie, frakk and the other guys, now I can to show to you my newborn 3DOF project

I am in full test time but unfortunately my third Jrk12v12 is broken so I have to stop main experiments for the time I need to buy and to have another one jrk12v12 .

first to see that one of the Jrk was broken, I could do various experiments about how many amps my motor draws and especially many tests about mechanical limits of the three platform legs in the various type of movements and inclinations.

I am very sad about my broken jrk because without this forced stop now I made ​​my first experiments with the rFactor running under the X-Sim

Sure the joy about my creation is very high but believe me, to be almost to the top and not be able to reach it is a very bad feeling.

If you want to understand the Jrk problem you can go to this link (pololu forum):
forum.pololu.com/viewtopic.php?f=15&t=3735

Now I am forced to do just the tests about left and right leg with my stern leg in stop condition. Better than nothing.

Here the pics:

[Frakk]

Good job Aldo! I would try to make the moving upper part much lower for stability and safety.

Have you tried if the motors will be strong enough for vertical movement?

[eaorobbie]

wow looking good but agree with Frakk on height of top platform reducing this will take some forces of the motors,
power for vertical lift cant see a problem mate tested my units on me joyrider with 200kg in chair for extreme weight test and not slowing in motor movement or excess heat. Units can dead lift 150kg easy, so when ya times the power by 3 plus spring backup cant see an issue.
Jrk problems the only issues i've had is burning out the inbuilt power regulator because of hooking in too much amps, unit still works but needs a usb connection at all times or the max and min values wander, still go as a demo unit but.
If ya havent got any burn marks on the card or strange electrical smells it all should be still go. Something to try would be a firmware re flash which ya can download from pololu v1.3 a strong power spike or too much amps can cause the firmware to corrupt sometimes.

Again looking good, didnt hear from ya for awhile, so I thought ya shelved it, but I was wrong looking good.

[kubing]

nice implementation. good effort bro.

[AldoZ]

Thank you all dudes! your help and support it's great!
Today I am very happy 'cause I find the jrk problem! not broken, just my weldyngs was not perfect!.
Now new weldings done and the Jrk working great!

@Frakk :
About height, yes, it's a bit too tall.. just I had made the project mantaining the original dimension of the spring (a car damper). Sure I will to follow your words and I will cut about 30/40 cm the total height.
ehh Frakk I remember when I wrote the first post on this forum.. you just start to help me since now (and it's really good for me to show to you my progress!) and without your "initiation" and help in this forum I could not absolutely be at this level.

@eaorobbie :
mate in first I need to say to you that your idea of using winches was great! (an idea that allow to start to think about making a 3DOF!!) and a big thank you for all!

I am very curious about the amps draws when the motors are at full cycle.
When I try to move my motor (changing continuosly the motor direction) at full cycle (without wheight to be lifted) I get my motor draws 7/9 amps.
Maybe It's not the best thing in the word but is better than nothing.
I think that when the platform will lift the weight of the final configuration so the total amps will be over the 12 of the Jrk specifications..... lucky the jrk12v12 can handle peaks of 30amps but this matter remain to be seen until I run the new tests (tomorrow!).

About my third Jrk lucky it's working! just my weldings was really ugly!
Please teach me about your problem of the the inbuilt power regulator burned.
how many amps were handling? And what do you mean when you say that after the accident you need to use the usb connection at all the time? I have already my jrks all the time connected via usb!!

@kubing:
Thank you!!

[eaorobbie]

to start with i had my jrks hooked to a mastro rc controller, biting too much off attempting a 6dof first up, quickly changed to 2dof first off, then discovered that i could talk to the jrks directly took a while to work out because the pololu crowd just kept saying read the manual.
We live on a property so power is not too clean got a 45amp surage through the first power supply i used, modifed pc psu, not good, heard the pop saw the smoke,but by the time i hit the power button too late, hence now running 20amp fuses between power supply and jrks, and a decent filtered power supply, no worries now all safe as houses. Only used the usb on the jrks to set the mins and max then unplugged them from the usb and let the maestro go to work.

Still hoping to use the rc card to build a servo controlled dash as xsim talks to the maestro with ease and hold 12 servos so that a dashboard with 12 guages cheaper that any bought unit but a little involved in setting up.

And mate the help that goes around here is getting better just with there was more people like Frakk and kubing would make it alot more frendlier for new guys just coming in, there a bloody lot to get ya head around, motion sim building is not easy, but once ya got the basics it the ideas begin the flow, so thanks to all i wouldnt have a sim without their help and pats on the back.

[AldoZ]

@eaorobbie:

ahh very unlucky mate and I am thinking too about the use of some fuses to avoid bad amps peaks. This motor controller is great but I don't want to risk to broke it.. Italian distribuitors is empty of Jrk12v12 and order from USA can mean over a month to have another jrk...

Here my video of today, first decent tests about mechenical stress (plus an always good jorge baker song ):
(The video is edited without the anoyng pause times)

test done using the JRK configuration utility
1/2 of motor duty cycle
1/6 of motor accelleration
(really far from the maximum obtainable performance! )



PS:
at 1:15 sec you can listen the "CRACK" sound... just I need to add some another iron strips to join better the 2 parts of my wood dais (the forces start to be high!)

PS2: at the finish you can notice the "drift" of my platform.. this is cause I exceeded the maximum height of the spring with the motor arm.


Soon my vids with X-Sim!

[Frakk]

It is great to see that my help doesn't go wasted guys.

[kubing]

too bad if you gonna wait for a month..maybe somebody around here have some.

[AldoZ]

Hi guys, some news here:

In first, for the first time I tried to use X-SIM (3 axis) using test palet with very good results!
I tried to use test slider 21 to move left and right legs cloned and inverted (when I push up the slider so left leg go up and the right leg go down) plus stern leg moved using slider 22.
All very good and with a good speed (perhaps closer to flight simulators that racing sims).

The real first problem is that my JRK can't obtain the maximum available motor power!
With my tests using max duty cycle and max acceleration I obtain that the single motor can lift more or less 70/75kg slowing down slightly. If I try to lift over so my motor get slowing much and my JRK get overheats (I get maximum currect exceeded from JRK config utility many times).
So I wanted to take my doubt off (it's the motor or the jrk limitation?) and I try to use the motor directly connected to the battery to try to lift up 100 kg and I obtain that the motor lift up 100kg easly without slowing!. Then the problem is from the Jrk.
Just the Jrk can not give enough current to the motor for lift up weight over 70kg. (jrk limitations are 12amps continuosly with 30amps peaks)

I want to says to you that in the final configuration sure my platform no plans to put 70kg directly in the vertical of my motor leg as these tests eh! But I would more!

It's not the end of the world.
I have again 210/225 kg (the 3 legs summed) available to be lifted with my platform (I figured my final configuration with an human onboard + all racing or flight devices will be more or less 130/140 kg) but maybe I find a way to obtain the 100% motor power using the Jrk.

Sure, I can raise the max amps from 12amps to an higher value from the jrk config utility but sure I risk to burn my Jrk.. so today I will to try to using some relay to obtain my motor get the amps from these relay instead from the Jrk!.. The jrk will provide just a very little amps value to the relay, just to excite these. So later, will be the relay to provide the amps to the motor.. theoretically I can get 100% of my motor power.
My english is not enough good to describe correctly this process but today I will try this solution and later I will can says to you if I had a good result.