Update: My 2DOF + homemade shifter

Hi -again

Please, don't fight with each other, you're all helping here

@eaorobbie , indeed that rig is made of a bunch of crap There isn't a single shop around where I can buy steel unless I order industrial quantities... so I dig into the garbage of my employer and re-use old rusty stuff. E.g., the motor mounts, levellers and rods are pieces of metal from an old and strong TV wall mount!

Anyway, I'm now back in the garage for some setup I've applied both @eaorobbie and @bsft settings and still the same issue. I actually have to reduce the Max duty cycle and Max acceleration otherwise the problem occurs very often which makes me thinking that I have an over power issue. FYI, I use one PSU per motor, those being rated at 700W (each of course).

Could be, have you got a car battery you can hook up?

Unfortunately not I'll try to find this to see if the PSUs are the problem. Also note that I'm using 6mm2 cables so I'm sure the power passes

Now it's clear, when I was testing again, my PSU shut off (and restarted after unplug/replug). There must be something I can do...it's rated for 700W.

[Edit] Now it happens more and more often, even with the rod unplugged from the motor (= no load). My PSU don't have any internal cooling system, I believe they are made to be cooled down by their server. I've added a fan in front of both but it might not be enough

Ok yes fan on psu will help them a bit.
Ok now you can wind them down a little and test.
Duty 500
Acc 200
amps 20

use pid P 0.39 D0.39 even drop P to 0.2
if stable slowly increase duty and amps and P.

Another might be to pack psu in parallel so and have both Jrk draw from there.

But it sound like not enough amp peak avail to jrks.
Sorry

I've just tried to force air through one PSU with a compressor and it worked Guess what, I'm not going to use this rig with the air compressor next to me

I'll look for other PSU... any recommendation there? Some well approved high power PSU? It is maybe easier to use a car battery in fact? In parallel with the PSU?

join both the pos and neg leads so pos from both Jrks and pulling from both supplies and both neg and connected to both gnd on the jrks, please be careful wired right you will have double the amps and 12v wire wrong and you will have 24v and the same amps.

Google wiring batteries in parallel mate.

I would recommend a 30amp Led Driver like this -http://www.ebay.com.au/itm/85V-265V...id=100011&rk=7&rkt=8&mehot=pp&sd=251363172812

This might work for driving one motor but the problem will be the same when using both motors. I now think that my initial problem was that I did not provide enough power to my motors so they couldn't change direction and produced this weird electric noise. Now that I authorize more power...the PSU is limiting the whole setup.

I'll go buy a cheap car battery today and see how it goes (it's not lost, an extra car battery can be the opportunity for new projects if it does not stay in the rig )

So, the car battery is plugged now...still not good. I have to decrease the max duty cycles to 300 and acceleration to 200 to avoid the problem (actually I would need to decrease even more to be 100% it's not gonna happen in game).

To me it's a power issue, the little JRK might have reached their limit I'm afraid :/ When the motor stop responding, I have an error 0x0004 (motor driver error)

Hi @Vef445 I have all my PSU's in parrarell like robbie said and custom fan cooling it's very easy to do.



Hope this helps a little

My power setup, poor man PSU and Battery is in protected with fan filter air case too.

Nice mounting @SilentChill , very impressive. It might help later, for now I have a battery car plugged on it and it's still bot good

What PID as you should be able to run it flat out, or is there an issue with reverseing motors itself ?
Have you driven motors just with psu to check with no jrk to test direction. ?

Yeah I posted at the same time you were posting about getting a car battery lol ahh well nevermind

Thanks for the help @eaorobbie. I can run the motors both direction with constant speed with no problem (I've tried by removing the pot from the motor). Whatever PID config I put, same result as long as I don't reduce the Max duty and Max accel.

Here is my configuration:

I keep trying and I found out that it's not exactly when I switch motor direction multiple times that the problem occurs, but when I "throw" the cursor too fast in any direction, like from one end to the other.

Some more discoveries tonight If I refer to the seller website, my motor is 4700rpm: http://www.motioncontrolproducts.com/pdfs/pmdc_2.pdf

On their eBay announce, it's written 65rpm (with 60:1 gearbox) but it's obviously wrong. As you said earlier @bsft , motor >4000rpm will be a problem Do I have any other solution than replacing my motors?

Just checked his post, lots of good info and appears to be the same issue that I meet, which gave me hope

I went back to my initial setup which was (surprisingly!) not that bad. I reduce the Max duty cycles and max acceleration, put the break back on and voila!


This works a lot better! With the indications given by @bsft and @eaorobbie I am also much closer to the proper PID configuration. The more I play with it and the more I understand the effect, so I'm now getting close to something good.

Tomorrow I'll install simtools and give it a try. To be continued...I'm sure I can spend a lot of time fine-tuning the whole setup. Oh, and by the way, the break is barely noticeable (I might reduce the break time though) and the whole the reaction time/speed seems to be reasonable if not quite good compare to the many videos I've seen here

Beawdy mate!