I'm trying to build a control panel for train simulators with an Arduino Leonardo

Projects Programming
1

I use an Arduino Leonardo and a 10k linear potentiometer. The potentiometer has a rotation range of 270 degrees, of which only 110 degrees are used by mechanical stops. Now the 100 degree rotation range is converted. The current position of the pot is set as 50%. so that a driving brake lever for train simulators works. that works up to here too. Only in the range of 50-100% does the value increase too quickly.

#include <Joystick.h>

// Joystick-Objekt initialisieren
Joystick_ Joystick(JOYSTICK_DEFAULT_REPORT_ID, JOYSTICK_TYPE_JOYSTICK,
                   0, 0,                 // Keine Buttons, keine Achsen außer X
                   true, false, false,   // X-Achse aktiv, Y und Z deaktiviert
                   false, false, false,  // Keine Rotation
                   false, false,         // Keine rudder/throttle/accelerator
                   false, false, false); // Keine Hat Switches

const int potentiometerPin = A0; // Potentiometer-Pin
const int smoothingFactor = 10;  // Für Glättung (höher = mehr Glättung)

int rawValue = 0;                // Rohwert vom Potentiometer
float smoothedValue = 0;         // Geglätteter Wert
float zeroPoint = 0;             // Dynamisch kalibrierter Nullpunkt
const int potentiometerMin = 0;  // Minimaler Wert vom Potentiometer
const int potentiometerMax = 1023; // Maximaler Wert vom Potentiometer

void setup() {
  pinMode(potentiometerPin, INPUT);

  calibrateToCurrentPosition();

  Joystick.begin();
  Joystick.setXAxisRange(-100, 100);
}

void loop() {
  rawValue = analogRead(potentiometerPin);

  smoothedValue += (rawValue - smoothedValue) / smoothingFactor;

  // Kalibrierte Werte für X-Achse berechnen
  int calibratedValue = map(smoothedValue, potentiometerMin, potentiometerMax, -100, 100);

  // Langsame Reaktion im Bereich von -100 bis +30
  if (calibratedValue <= 30) {
    calibratedValue = map(calibratedValue, 100, -30, 100, -30); // Langsame Skalierung
  }

  calibratedValue = constrain(calibratedValue, -100, 100);

  // Werte in den Joystick schreiben
  Joystick.setXAxis(calibratedValue);

  delay(10);
}

void calibrateToCurrentPosition() {
  int currentValue = analogRead(potentiometerPin);
  zeroPoint = currentValue;
}
2

Any chance that you're using a logarithmic potentiometer?

Have you printed the ADC values based on position of the potentiometer. Does it change in a linear fashion? 0 deg -> 0, 90 deg -> 340, 180 deg -> 680, 270 deg -> 1023.

3

Your pot should say ‘B’ or LINEAR…. alongside the value marking.

the alternative that you don’t want is ‘A’ or LOG.

4

I just had the ADC values ​​read out via the serial monitor. these increase linearly until 1023 as expected

5

You could print some values to see where you are going wrong.

I'm in transit looking through the tiniest of windows but I see

  smoothedValue += (rawValue - smoothedValue) / smoothingFactor;

which might be better if smoothinFactor was a float, and

    calibratedValue = map(calibratedValue, 100, -30, 100, -30); // Langsame

which is the same as doing nothing.

But printing. Anywhere you have the least doubt about what the numbers really are.

a7

6

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