new to sim

Early man based the number system on 21 but early women said that it was unfair

Started on electronics over the weekend. Keeping an old computer around, sure came in handy for parts.


Ready for testing. I remember watching a video on the setup of the JRK's and motion limits on the motors, but can't seem to locate it. Can anyone direct me to it?

did you put heatsinks on the big chips of the JRKS? They will need them

EDIT, sorry, more than likely yes, I can see them in the photo, just not on the jrks

do you mean the various commands for the jrks?
motion limits on motors?

Yes, It was on setting the motion limits on the motors

motion limits? or feedback limits?

motion limits

anyone had a problem with windows 8 and the JRK's? hooked them up last night per the "Quick Start Guide" and windows 8 would recognize it then drop it then recognize again ect. This is the one on com 4, com 6 stayed linked. Any ideas?

Try reinstalling the driver, it is digitally signed, another common issue is the quality of leads and the port you plugin them into, try different combinations, and this is only a windows 8 issue, I was running Windows 8 but registry became corrupted and the Jrks would not register as well as my Ard for my Dashboard, mmm Windows 7 was on a hour later, and no issues yet. Try reinstalling the drivers for them. And make sure you install Net Frame work 4.5 and its updated , Windows 8 is a pain for this. But does work.

On setting up the Jrks that's not too hard its is documented here in places, but no time as of lately to write it all into one document. Sorry.
But when you ready let me know , quite happy to spend sometime running you through the process.

thanks Rob. I have ordered some new USB cables as I switched them around last night and the one now on com 6 kept dropping.

JRK firmware is 1.4 and Net 4 has been updated. I do plan on running this on a win 7, but do not want to lug it to the garage, so using laptop (win 8) for setup.

I did however try to get the one motor to run with no luck. . The motor shows running in the JRK software and it took my min and max limits, but when I clicked run, no movement.

Do the pots need to be mounted before I try to run the motors? I had them wired to the board, just not mounted.

Thanks in advance for you help and I will be more than happy to write up a step by step procedure with your approval once we get it running.

It would be best if pots are also mounted on the motors to test, so you can do proper setup.
How did you took Min/Max in JRK utility, rotating the pot shaft with your hand?

Also, if you didn't used the pot at all and you just moved the motor arm up and down to set Min/Max, you basically didn't do anything, because the pot gives the feedback to the JRK utility on how much to move the motor.

In JRK utility there is also a slider, so when you press Run try moving that slider to test your Min/Max limits.
I think when you press Run without using the slider, the motors will not move freely.

@prodigy that is correct.
The pot gives a feed back reading of 0-5v to the jrk and is in respect the position of the lever.
Please connect the pot to the motor, either direct to the end of the shaft, the easiest way.
Or with a lever and connecting rod, or even gearing. Once complete the sets are easy if following Pololu's guide.

In the Pololu Configuration Utility- Select the Jrk you wish to setup.
(hint look at graph and move a lever that a pot is connected too, if graph moves you have the right lever.)

FeedBack Tab
Click Reset to Full Range
Click Apply settings to device
Click Learn
Now move the lever to the Max position of Movement required
Press Ok
Now move the lever to the Min position of Movement required
Press Ok
Click Apply settings to device

Now Max and Min position is set (an explanation on setting this is pic below) we can move on and set a base PID

PID Tab

Set a Proportional Coefficient = 0.4
Set a Integral Coefficient = 0
Set a Derivative Coefficient = 0.5
These are a fairly stable base for most 12v dc motors , I have found over time. We can tune up later to help motors support weight and sharpen it stops.

PID period (ms) = 20 . Is a base can be speed to 10 but the feel in motion is no better but can be changed later.
Integral limit = 2000
Check - Reset integral when ...... to help any error clearing in pid calc.
Feedback dead zone = depends if the value in the scaled Feedback is flicking up and down 2-3 values then set to 3. Needed with cheap pots.
Click Apply settings to device

Ok now we have a base pid that the Jrk will use for its position calcs we need to move on and set some motor speeds and accels.

Motor Tab

Set PWM frequency to 20
Set Max duty cycle to 450 to test later you can increase or decrease
Set Max Acceleration to 600 let the Jrk decide the speed needed to reach its position. (faster the better)
Brake = 0 as we don't actually brake, we are always changing direction.
Set Max. current (A) to 0 let the Jrk decide how much boot it needs, this is where heatsinks and cool play their parts.
Current calibration , leave as default. We don't need it, not for position control.

Set Max duty cycle while feedback is out of range to 600 as if it bounces over or under we need to return to the proper position as soon as possible.
Set When motor is off to Coast unless your motor contains a electrical brake, most dc motors don't come with them.
Click Apply settings to device

Ok now we need to test that we have the Jrks motor direction and pot direction going the right way.
Ok set the lever to about its centre(middle position) and while holding the connection rod in place with a little resistance so it doesn't over or under shoot badly , happens sometimes with cheap pots,
Press Detect Motor Direction
Follow the instructions and motor will kick , it will tell you nothing then all is good , but if it tells you it needs to be inverted click Apply setting to device

Now we are ready to test this motor.

Input Tab

Set Input mode to Serial.
Check USB Dual Port
Check Automatically set Target in the bottom right.
Click Run Motor
Now you can set the target with the Manually set target slider also leaving cursor over the slider you can press page up and down to step the slider or home and end to go to the min and max set.
Test it while look at the Graph if you double click the graph it zooms out and you should be tuning to make the blue line move closely to the red line. Will explain that later.

Need to have both motors moving correctly before even starting to work out SimTools , actually makes SimTools setup a breeze after this.

Hope that's not too much to grasp, the basic setting up of a Jrk.

thanks for the info @eaorobbie and @prodigy. @prodigy , you are correct that I turned the motor levers only. When I saw them register in the JRK"S, I thought that was a good thing. I will take the info from above and also have been reading the complete set up guide that I found from @earobbie. The quick start is kinda confusing for a newb. Thanks Rob for taking the time to input the info above.

@Tendonitus lets get the Jrks setup correctly and moving then I can take you through the steps in setting SimTools up with the Jrks.
Lastly how to patch the game and build your first base motion profile, I do see the issues the Quick Start create for newbies who have had no sim experience. But overall for Sim Builders it works. mmmm We need a Newbie Quick Start or proper Guide.

@eaorobbie , spoke with pololu yesterday and the one board that kept popping in and out of windows is bad. I'll send in back Monday for them to check out and have ordered another one to keep progress moving.

I' ll get the pot attached tomorrow to the board that works as today is race day for us. Don't like the idea of hot glue, so will drill a hole in the pot shaft and attach with a pin.

Not sure how good these pots are as they are a radioshack version and only $4.00.
http://www.radioshack.com/family/in...um=RSCOM&znt_source=CAT&znt_content=CT2032230
10K-Ohm Linear-Taper Potentiometer
Model:
271-1715
| Catalog #: 271-1715

Your thoughts?

Hi Tendonitus,

I tried those RadioShack pots on my first build, they were very jittery so I removed them and replaced them with better pots.

would you send me the specs on the ones your using

http://www.radioshack.com/product/i...ce=CAT&znt_medium=RSCOM&znt_content=CT2032230


I tried four of these. I use them now on my button boxes. Jittery feedback is ok for course adjustments but for my motors they were horrible.

@Tendonitus I had used theses http://www.jaycar.com.au/productView.asp?ID=RP3510
for almost 12 months before changing to hall effects, they were a little jittery but with setting the scaleback valve and using 512 sample a sec in the Feedback tab smoothens the pot movements back out, to perform acceptable motion, only reason to replace them is I was only getting a week's use out of them before wearing them out. lol
But better pots will result in a better feel, the Ard doesn't do any smoothing , etc so jittery pot can not be compensated for.
And yes hot glue is a bad idea, breaks too easily on fast direction change on motor.
I setup my pot and jrk, then move the pot in the jrks graph until its close to 50% with my lever sitting in its middle (centre) position and then drill through and pin it in that location. So I know I have the same amount of deg up and down. Then I set the feedback to the movement I want.