Tutorial SMC3 Arduino 3DOF Motor Driver and Windows Utilities

Hi RufusDufus,
No i did not do that, after i tested everything in SMCUtil (all axis worked fine) i'd used Simtools to test the 2dof movement.
it was not to responsive (moving the sliders above 40% did move the motors), but then i used the calibration tool (tuning center) to set the min/max
values, and i did it with the game LFS of course
Now the movement in the game engine (Rool & pitch) is very responsive.
After i saved it i did a couple of laps with LFS, but exelerating and braking doesn't give the desired effect of roll (tilting the platform to the front or back) it does it when is use the settings in the gameEngine tool :-(

I'd tested it with Assetto Corsa and the thing i noticed is that the movement looks like it is Sway & Surge, in the game engine screen it displays the right game and Roll & Pitch, thats also the movemet i captured in Tuning Center.
Maybe this brings some light in the darkness

(in the mean time i'm going to reset al my settings and start all over again, maybe it helps)

Hi Dedas, for braking you want the Surge DoF. That will tilt the car forward and back under braking and acceleration. Roll is the side to side motion caused by orientation of the car (such as sitting on the side of a hill).

Hi Historiker,
You are so right this explanes the strange behavior.



Now its seems to work, as a matter a fact a bit to good (i got kicked out of the seat now when i'm cornering and hitting the curbs)
Got to tweak it because the rig is devastating
I'm testing now with surge to emulate accelerating and breaking, and sway to emulate the g-forces when cornering.

Yes, my wife made be put a harness in mine because the violent movement tossed me out one day, lol. I was riding a roller coaster

Edit: Those are really nice graphics of the forces, do you have high def versions of those?

I agree we could add that to the manual. and FAQ section.

Done! FAQ15

Hi @RufusDufus this evening one of the two psus stopped (I have connected one PSU to one Monster Moto separately). After powering the psu and starting the SMC3 utility nothing happened. The winches was dead. Turning the potentiometer did not give any feedback in SMC3. First I thought about an hardware issue (Monster Moto, potentiometer etc) but I tried (as one last solution always) the reset button onto the ardunio - "et voila" it works. Any suggestions?

EDIT - I have a short circuit but do not know from where and why. Perhaps the Moto Monster (the new one) is blowed

@Pit, there are a couple of reasons a reset of the Arduino would have worked

1. If the failure caused current spikes or significant noise on the power/gnd lines it could have caused the Aurdino to latch up and need resetting.

2. More likely though, when it failed and you turned the pots, you turned them into the "Limit Zone" setup in SMC3Utils. If this happens the SMC3 code shuts down the motors for safety until reset either through SMC3Utils or a hardware reset. Note also if you leave the sime tilted such that the pots are in the limit zones when you power on the code will shut down the motors immediately making it appear as though nothing is working. Just make sure the sim/pots are somewhere close to center when powering up.

As for the short circuit... I still think the way you are connecting the two drivers together could be causing problems (assuming you are still doing this). Think about it this way... Assume the motor is being driven and you have +12V output on Moto Monster A1 and GND on B1 and the same for A2 and B2. I understand you are connecting A1 and A2 together and B1 and B2 together. Now we reverse direction... A1 goes to GND and B1 to +12V. IF the second driver takes even a ms longer to switch its outputs then you (for a very brief instant) have A2 still at +12V and B2 still at GND. With A1 connected to A2 you therefore have +12V connected directly to GND for that brief instant. Now remember the PID algorithm is switching the direction at something like 20kHz so that is alot of times you are potentially connecting 12V to GND which may be over stressing your H-Bridge output driver chips causing them to fail or shutdown early.

I personally would go with the recommended wiring from the driver datasheet - it can still have the same problems if the wiring is wrong however the risk is reduced because each side is driven by one driver IC.

@RufusDufus thank you for your efforts. I tried to wire as described in the diagramm(s) and get the same polarity on each side. (A1/A2) and (B1/B2):

2 (Motor 1 H-Bridge ENA) ---------------7 and 8 (INA1 and INB1)
3 (Motor 1 H-Bridge ENB)----------------4 and 9 (INA2 and INB2)
9 (Motor 1 PWM) --------------------------5 and 6 (PWM1 and PWM2)

But now I have no pot feedback onto the Monster Moto. If I turn it nothing happens. The output is 12v continuous (PWMmax = 10 !). The direction drive LEDs are always off. Did I forget something?

@Pit, Ok, First of all the wiring is correct as per the datasheets. In this configuration you connect A1/B1 to one side of the motor and A2/B2 to the other side of the motor.

Just let me just make sure I understand...
You are getting say +12V on A1/A2 at the same time and GND on B1/B2 at the same time? That definately doesn't sound right? In this case it seems something is wrong with the Moto Monster board or the wiring.

Or are you saying you get +12V on all A1/A2/B1/B2. This is OK in terms of outputs it just means the motor is being braked. So in this case either the Aurduio thinks the motor is in the correct position, or it has shut them down for some reason, or its not outputting the correct signals, or the Arduino board is stuffed?

A few things to check
1. SMC3 is configured as MODE1 for this setup.
2. When running windows SMC3Utils it is not saying the motor is OFF in the top left of the window
3. When running windows SMC3Utils you can see the pot input moving as the pot moves

A1/B1 have the same polarity, meaning if I connect them I have zero V. If I connect A1 to A2 I have 12V.

Passed.

Passed

Passed.

IMO there seems to be an issue with the PWM output.

To be sure two pots are connected to the arduino.

1. KP=400, PWMmax = 10 or more. A1 and A2 =12.55V (or -12.55V if the pot is lower or upper) . If the pot is within the zero line no voltage output is generated.
2. KP=400, PWMmax = 0 (!). A1 and A2 = 11.88 V output. If the pot is within the zero line no voltage output is generated.

Conclusion: Due to the LEDs are not lighting and there is no correct PWM signal there seems to be an issue with that.

UDPATE: ditto failed using the Duemilanove 2dof firmware! Only power ON (+ or -) or OFF (pot within zero line) , no LEDs, no continuously increasing pot feedback. Perhaps there exist different VNH2SP30 revisions.

@Pit, Ahh, the LEDs will never work in this configuration. Because we are using each single driver as half of a H-Bridge each one is always set at +12V brake mode or GND brake mode.

ie. A1 and B1 will always be set to match each other (12V or GND) giving us double the drive power because we are using both the highside and lowside switches for one motor terminal. If they didn't ALWAYS remain the same voltage as each other then you wouldn't be able to join them together!

A2 and B2 also must always be the same as each other.

But when the motor drives in one direction you will see A1=B1=12V and A2=B2=GND
When the motor goes in the other direction A1=B1=GND and A2=B2=12V
When the motor is stopped you could have either A1=A2=B1=B2=GND or A1=A2=B1=B2=12V

Hope I'm not confusing you

prfff

I am going to try out it now. I have one more bridge in reserve

Good luck... maybe your other h-bridges are still ok also?

it works!

If you want and if you are agree you can implement the half-bridge option of the Monster Moto into your first posting.

Wow, looks great Pit!

yeah I am very happy now. Ready at last. After the video was taken I could set the values of heave more aggressive without stopping the winches. Thank you all for your efforts and time you have spent.