Parking Sensor problem



  • Just completed building the parking sensor project and interfaced it to a Vera edge via NRF2501,s and every thing works. The problem I am having is the sensor (monitoring it with serial monitor to confirm ) when a vehicle is parked it changes states ever 5 seconds from car parked to car gone . this does not occur when vehicle is actually gone . It reports correctly. I have verified connections, reloaded the sketch and now I am at a complete loss . Any suggestions .


  • Mod

    Welcome @mikeg291 !
    Uncomment this

    //  Serial.println(fullDist);
    

    and see what the serial output look like. That should give a clue into what is happening.


  • Contest Winner

    @mikeg291

    It could be that transient sound waves are reflecting/scattering around and affecting the readings. The NewPing library states that 29milliseconds should be the shortest delay between reads.

    Sound travels a little more than one foot in 1millisecond so you have an inherent delay in an empty garage; 15 feet each way, for example is about 30milliseconds from ping to read.

    So, if you insert a delay(50) after you obtain the distance you may leave enough time for all of the sound to be absorbed or reflected away.

    void loop()
    {
      unsigned long now = millis();
      
      unsigned int fullDist = (sonar.ping_median() / US_ROUNDTRIP_CM);
    //  Serial.println(fullDist);
      int displayDist = min(fullDist, MAX_DISTANCE);
      if (displayDist == 0 && skipZero<10) {
        // Try to filter zero readings
        skipZero++;
        return;
      }
      delay(50);  // try this
      // etcetera
    


  • @BulldogLowell said:

    @mikeg291

    It could be that transient sound waves are reflecting/scattering around and affecting the readings. The NewPing library states that 29milliseconds should be the shortest delay between reads.

    Sound travels a little more than one foot in 1millisecond so you have an inherent delay in an empty garage; 15 feet each way, for example is about 30milliseconds from ping to read.

    So, if you insert a delay(50) after you obtain the distance you may leave enough time for all of the sound to be absorbed or reflected away.

    I second this. Built the sensor with a neopixel ring and the leds go berserk when I am about 3 cm away from the sensor with my hand.



  • Problem solved Turned out to be a bad sensor and with mfalkvidd 's suggestion troubleshooting was a lot easier . Thanks


Log in to reply
 

Suggested Topics

  • 3
  • 15
  • 24
  • 3
  • 1
  • 2

0
Online

11.2k
Users

11.1k
Topics

112.5k
Posts