More work on the Sharp sensor

The sharp GP2Y0A02YK0F Infrared distance sensor has a nonlinear voltage versus distance output specified by the datasheet.

I took some positions on that curve and made my multi-linear mapping...

void setup()
{
  Serial.begin(115200);
}
void loop()
{
  float dist = getSharpDistance(0);
  Serial.println(dist);
 
  delay(200);
}
float getSharpDistance(int sensorPin) {
 
  int sensorValue = analogRead(sensorPin);
  float voltage = sensorValue * (5.0 / 1023.0);
  float dist = 0.0f;
  if (voltage < 0.4f) {
    return 0;
  }
  else if (voltage < 0.8f) {
    dist = floatMap(voltage, 0.4f, 0.8f, 150, 70);
  } else if (voltage < 1.5f) {
    dist = floatMap(voltage, 0.8f, 1.5f, 70, 40);
  } else if (voltage < 2.8f) {
    dist = floatMap(voltage, 1.5f, 2.8f, 40, 15);
  }
  return dist;
}
float floatMap(float sourceValue, float sourceMin, float sourceMax, float destMin, float destMax) {
  float sourceRange = sourceMax - sourceMin;
  float percent = ((sourceValue - sourceMin ) / sourceRange);
  float destRange = destMax - destMin;
  return destMin + percent * destRange;
}

BTW I just found Jeremy Blythes blog . He used a formula he found on Sparkfuns page for the sensor
I think the source is jmatson11 and the formula is

"Distance = 16.2537 * x⁴ – 129.893 * x³ + 382.268 * x² – 512.611 * x + 306.439 *Where x=Voltage read on ADC and Distance is in cm."

I must try this formula!

The sharp sensor attached to "Flip"

I attached the sensor to Flip, just under the ultrasonic sensor, giving Flip double vision. Initial tests seems fine but The USB-cable for the Arduino is a little bit bad positioned so it blocks the sharps cable. 

I really should take the droid out to the shed to drill some new mounting holes for the arduino board. I just used two existing badly spaced holes and placed the arduino between them.