2DOF with wheelchair motors

Oeps I forgot to add the line in SMC code.

Without the line motors work in SMCutils.

Problem now is when I add the line... Can't set the motors on and pots give no feedback.

Any ideas of what I am doing wrong?

Also I just found out that GameEngine does not connect to the simulator before I manually set motors
on ON in SMCutils.

When I have done that I close SMCutils and open GameEngine and then it is connected.

Does your setup-routine look like in this picture and did you connect the arduino AREF-pin to +3.3V ?
I have highlighted the relevant positions.

Ok I see... I did it like this.

void setup()
{
analogRefence(external)

and then the rest.

So I put it in the right order and uploaded again. Same problem in SMCutils.

When I start SMCutils it starts up like in the picture. Maybe I have to calibrate
the pots again?

Hello Jeroen,
I have just tested the new wiring with a brand new arduino on my bread board with two scale modelling servos. It works just like by my sim.
So i'm sorry i can't help you.

Ok Bernd, first of all thank you for youre help. I just wanted to try it out because I am annoid by the motor noise.

Maybe I destroyed the arduino because I did not modify the code befor using the new electronics?

I have checked the wiring...

5v goes to pot with 1m ohm resistor on the signal line.
added 3.3v line to the positive of the pot wich is connected to the aref line on the arduino.

I will try a new arduino...

Here are pics of the finished dashboard housing:



The next steps to be taken:

• complete the dashboard with switches and buttons
• build a diy H-shifter
• build a diy pedal set: brake with load cell, clutch and accelerator with hall sensors
• inner cover under pedals and seat with black carpet

Lookin good bernd

The dashboard is finished. Here are some pics:



I have chosen a Arduino Leonardo (in this case a pro micro), because it can output keyboard commands directly via USB. There are also three MCP 23017 connected via I2C to expand the Arduino by 48 I/O ports.

Great work! Looking really good

Impressive Bernd, Keep it up.

Thanks a lot for your positive feedback !

After having twice a shortcut in an IBT-2 H-bridge, which ended in multiple revolutions of the motor levers and ruin my feedback pots, i decided to order a Sabertooth 2x32 and two quadrature encoders.
I have removed the electrical brakes and a part of the casing from my wheelchair motors to have place for mounting the encoders directly to the motor shaft.
Now i have about 8 revolutions from the motor (= 8 x 500 = 4000 pulses) for +/- 60 degree movement on the lever. To find the neutral position of the levers there are two photoelectric fork sensors.



For the electronic part i've choosen an Arduino Mega because i need three serial connections:
One to Simtools, one to the Sabertooth and one via a bluetooth module to a PC (later perhaps to an android phone), to set the PID parameters and watch the movements of the sim.
I've written my own code for the arduino (similar to the SMC3 code), but with supporting the Sabertooth, the encoders and PID calculation with floating point numbers to get a better resolution.

It is definitely better to use quadrature encoders for feedback, because the "analog to digital encoders" of the Arduino are very simple and always have little random jumps on the output signal, even if the input signal is stable. (Even the often used hall pots doesn't eliminate this effect). So there is often a need for setting a deadzone. Whith these decoders the feedback signal is absolutely stable, no need for a deadzone.

I would like to show my diy H-shifter, which is build with parts from a Wingman Strike Force Feedback 3D Joystick.
Here are the pics:



It's controlled by an Arduino Leonardo and a Monster Moto shield.
If the clutch is pressed you can enter the gears by pushing the stick against a resistance force(coming from the motors). If you have
overcome the force the gear locks. For the next gear you pull the stick back against a resistance force to the middle and so on.
If you did not press the clutch the gears don't lock and you will hear a grinding sound.
If you press the red button on the shifter, you have 5 seconds to enter the reverse gear.
So it is protected from accidentally entering reverse.

Very Nice!!!

Nice project !!! ,
i'm looking for a long time already how to hook up SMC3 with encoders instead of POTs. Would you share your SMC3 upgrade code with community ?

You're a genius man ... any vids ?

Thanks for your reply. Next weekend i will post a zip-file with the Arduino- and Processing3 programs. I can only post it "as it is" because i am still working on it. My goal is to get the Processing3 part runnig as an app on an Android tablet (to set the PID parameters and watch the movements of the sim). But this will take a while (i'm not a professional programmer).