Reasonably Priced 100A Motor Controllers

This weekend I'll have a little window of time to work with it. I repaired a PSU that was burnt and also configured the three PS to 19,5V. I'll reconfigure SMC and follow your steps to check how it works.

Can you tell me how to do that down time when the direction changes? is it in the SMC Arduino code?

Thanks for all the help!!

I have written my own 6dof version

Smc3 may have a dead zone ?

Yes, there is an option that allow to configure a Deadzone:

Deadzone: This creates a hysteresis zone for the motor feedback If you need values greater than 1, you probably have too much “slack” in your mechanical setup.

I never used it because my motors does not have that backlash/slack, Do you think modifying this option it will add a delay to the direction change?

Thanks!

The deadzone may help

Alternatively you could program a delay when the direction pins are swapped to give the driver time to catch up

Delay(100);

Did you try your motors on 12v ?

Ok, I'll find in the Arduino code where to put the delay.

I still not reduce the voltage to 12V coz if I do that I think the torque will decrease too. I'll start with 19,5V and I'll see how it performs.

Thanks!

Definitively I'll wait to test more deeply because the PS I fixed is not fixed at all xD

I'll need more power so at the moment I ordered a new PS and will continue when arrive

Also, a too high PWM frequency could damage the board, on my side with 2 motors rated around 733Watt, I set the frequency around 20 or 25.
Higher and the board get hot. Also I added a little fan on top of the heatsink to cool it.
A single motor doesn't even need the fan.

I don't know what happened with the power supplies. I can run the motors directly connected to the PS (te last still is running) and even with a spark at touch the motor run and the PS work happily (a massive spark that literally weld wire and the PS connection screw). If I connect each board to that PS still spark but both run ok. I don't know what is happening, monday I'll receive the two new PS so I'll try again.

Also will low the frequency to see if it helps.

Thank you!

Well, today I continued testing. I have till february 16 to return the boards so the intention is try all as I can to get it work.

Each board was connected to each brand new power supply (24V 50A 1200W) configured to 18V. I installed two capacitors directly to the PS output: one ceramic to try to filter some of high freqs coming from the boards and other big electrolytic capacitor to work as buffer. Also I installed four diodes per PS in parallel to prevent the PS from returned inverted current.

3 x 24V 750W Motors with worm gear ratio, output speed 60rpm at 95Nm torque each.

The levers lenght are calculated to lift around 170 Kg.

The tests was the follows:

PWM freq: M1=M2=20KHz, M3=31KHz
Kp: 170
Ks=Ki=0
PWMmax=120
PWMrev=50
Deadzone=2

1st: motors only, without levers, SMC utils detects well all the Hall effect and send the commands to the boards and the axis moves as expected.

2nd: I installed levers, cranks, chair base and chair (between 20 to 25 Kg of load). Test with sine wave and all works fine.

3th: Then start testing with Flight simulator and FlyPT Mover, almost all the movements were OK but very fast movements (touchdown makes a fast movement upwards) do not done it. The motor 1 and motor 3 boards starts to get warm.

For the next test I changed Kp to 200 and PWMrev to 120.

4th: Now the fast movements like the described above slightly works, M1 and M2 boards get warmer but still not very hot, I could still touch and hold it

Time to put more load .... 90Kg more (Me ), total weight 120Kg at most

I've configured that when FlyPT disconnects to the Arduino the motors go to park position (levers facing down) to facilitate sitting and stand from the chair. When FlyPT and Arduino connects again the levers raise up to the "neutral" or middle position slowly.

5th) I "climbed" to the chair and click to connect to Arduino, the chair starts to lift-of and just at the moment of reaching the midpoint PAF! one of the boards starts to smoke and reek.....again the same problem.

At this point I stoped the tests. All the PS are still alive so good for me. The weirdest thing is that the "burned" board still works, what is burned (always) is not the electronics, is the track. Due the high temperature the tin starts to melt and moves down letting the thin copper track nude and insufficient to manage/admit that amount of current and burn so I don't know what to think.

I still does not buyed the Sabertooth, as I mentioned I'm very busy now and somedays I can "escape" from my duty and disconnect working with the simrig.

All the sugestions will be apreciated. Thank you guys!!

P.S.: I cannot coded the delays because I'm not sure where to put it even after read all the Arduino code. I suspect that in the functions SetOutputsMotorX() (where the X is the motor number) there are a comment saying //Drive motor forward and I think there can be placed the delays (in the forwards and backwrds parts of the code) there. Next time I'll try that.

With 2 motor on the boards I had to use a fan because the green heatsink was becomming quite hot.
My 2 motors are ampflow e30-150 24v

Yes, I have a fan installed on each board too

Maybe 1 bad motor that is shorted inside. Is it the same connection that have blown than last time and also same motor? If so, I would maybe look at the motor.
Also if your motor are not efficient / strong enough, they are maybe consuming a more more than we think.
I know that if I stall my mother they both each 100amp each and I known ill blow the board with this much current
What are the model of your motor?

Also maybe just 1 motor per bord could work

Another thing to note, I'm using batteries, so the generative go back to the battery, yours is stuck on the motor and board, maybe that's why

I tested each motor separately connecting it directly to the PS and all the motors runs perfect. The boards that get hot are making a kind of breathing noise, it is a relatively low freq noise that comes and go like a breath, I don't know why.

These are my motors: https://www.alibaba.com/product-det...l?spm=a2700.shop_plgr.41413.47.49a4674fDAMyhK


How do you connect the battery? in parallel to the PS?

Thanks!

For the moment, I only use 2 batteries agm in series without any power supply dieectlty to the board with a breaker switch between. I recharge them after each use. This is temporary and eventually I will try to add a psu to keep de batteries charged most of the time when using them.

Are the batteries supplying enough current to the motors? As I can see the batteries that offers +120Ah are really expensive and it be mandatory to use two in series to sum 24V....300€ wtf xD

Im using 2x 12v AGM (38ah) each in series (total 24v). With my rig with 3 motors it work fine for between 1-2h depending of what im doing.

These are my batteries. https://www.batteriesexpert.com/en/...phr12-38-batterie-agm-12v-38ah-haut-rendement

Since you birun your system pretty fast, you could try only a 12v car battery if you can borrow one just for testing and see if the parts are working better. its not 18v but I guess 12v is not that far just for testing,
Anyway, test before buying as if this does not workaorund your problem, then that would be quite an expensive test

Next week I'll get a car battery and will try with it. Today I was testing again. Configured the power supplies to 12V and the motors moves well but the problem is still there, with the chair empty the boards 1 and 3 get warm, board 2 less warm. When I jump on the chair the boards starts to do a weird sound then I cut the power and immediately touched the boards and I noticed that are extremely hot so is not a voltage problem.

I also restart configuring Arduino code from SMC ut. and test with a Kp to 100, 90 and 80 (the minimum value to start moving) and also having the termal issues.

Have a good weekend, I'll update soon.

Weird sounds are abnormal; I experience complete silence on my end. If you have a multimeter capable of checking DC current (amps), you should examine the amperage flowing into the motor wires when you sit on it. Maybe the motors aren't powerful enough, and you might be consuming excessive amperage.
If I have to place a bet I think I'll bet on the too much amperage before the battery stuff,

Yes, I have a ammeter clamp and it is weird it only reads 5 amperes as much. Next week I'll check it with another one (not from Aliexpress).

You remind me, the weird eletric sound you heard, in the past I had that with other controller when I was experimenting with my rig for the first time and I heard that sound when I stalled my motors, it was the excessive current going into the IBT-2 at that time. and of course I blew it.