ARDUINO  2009  

HA FUNZIONATO  PERFETTAMENTE AL  PRIMO COLPO!!!!!!...

NON GUARDARE LA PROVVISORIETA'  DEL SISTEMA appena ho tempo ne realizzerò uno professionale.

 In seguito il programma memorizzerà temperature e numero di giri su SD CARD (mi servirà per il GEMP)

COMPONENTISTICA ACQUISTATA PRESSO FUTURAELETTRONICA di  GALLARATE.

FOTO INTERRUTTORE A FORCELLA   GP1A57      Euro 2.50

CIRCUITO STAMPATO  per lo stesso                             Euro 1.70

MOTORE a c.c. MOT2N                                                   Euro 2.00

RESISTENZA da 220 ohm

IL MOTORINO E' ALIMENTATO con 5 volt c.c.  da ARDUINO

Viene utilizzato l'ingresso analogico nr. 5  di ARDUINO

PROGRAMMA SCARICATO da INTERNET:

//
// This example shows one way of creating an optoswitch
// using an IR LED as emiter and an IR LED receiver as
// light sensor.
// On this case it acts as a tachometer to count the
// revolutions per second of an aeromodelism plane's
// propeller.
//
//           + GROUND                                 +GROUND          
//           |                                        |  
//           <                                        < 
//           > 220 ohm resistor                       > 220 omh resistor
//           <                                        <      
//           |                                        |  
//           |                                        |
//         -----                                    -----
//          / \    >>IR LED emiter >>>>>>>>>>>>>>>>  / \   IR LED receiver
//         -----                                    -----
//           |                                        |
//           |                                        |
//           + +5VCD                                  +  ANALOG INPUT 0
//
int val;
long last=0;
int stat=LOW;
int stat2;
int contar=0;
int sens=75;// this value indicates the limit reading between dark andlight,
              // it has to be tested as it may change acording on the 
              // distance the leds are placed.
int nPalas=2; // the number of blades of the propeller
int milisegundos=500; // the time it takes each reading
void setup()
{

  Serial.begin(9600);
  pinMode(13,OUTPUT);
}
void loop()
{
  val=analogRead(5);
  if(val<sens)
    stat=LOW;
   else
    stat=HIGH;
   digitalWrite(13,stat);//as iR light is invisible for us,the led on pin 13 
                          //indicate the state of the circuit.

   if(stat2!=stat){//counts when the state change,thats from (dark to light) or 
        //from (light to dark), remmember that IR light is invisible for us.
     contar++;
     stat2=stat;
   }
   if(millis()-last>=milisegundos){
     double rps=((double)contar/nPalas)/2.0*1000.0/milisegundos;
     double rpm=((double)contar/nPalas)/2.0*60000.0/(milisegundos);
     Serial.print((contar/2.0));Serial.print("  RPS ");Serial.print(rps);
     Serial.print(" RPM");Serial.print(rpm);Serial.print("  VAL ");Serial.println(val);
     contar=0;
     last=millis();
   }
}