Motion Sensitive Tesla Coil

Step 2 Code

Below is the code for the Halloween part of the program. When someone walks by less than 2m away and no one has passed by for 1.5 minutes, the Tesla Coil will turn on.

int transistor = 13;                                 //transistor base to resistor to pin 13unsigned long time = 0;int avgdistance = 0;void setup(){  Serial.begin(9600);                                //protip: plug in a serial lcd for quick testing  sonarSetup();  pinMode(transistor, OUTPUT);  delay(2000);                                       //give time for everything to get ready  for(int i = 0; i <= 30; i++)                       //get an average distance on how far away the other wall is  {    avgdistance += sonarPulseWidth();  }  avgdistance /= 30;  avgdistance -= 50;}void loop(){  int distance = sonarPulseWidth();  Serial.println(distance);  if(distance < avgdistance && (time + 90000) < millis())    //distance has to be less than the avgdistance away                                                             //and can't have been triggered in the past 90 seconds  {    digitalWrite(transistor, HIGH);    delay(500);                                      //turn coil on for 1/2 second    digitalWrite(transistor, LOW);    time = millis();  }}

Also, the code to run the sonar sensor is below.

                         //Sonar GND to ground                         //Sonar +5 to +5                         //Sonar TX -- Useless for this project                         //Sonar RX -- Useless for this project                         //Sonar AN -- Useless for this projectint sonarPW    = 5;      //Sonar PW to digital pin 5, 147uS per inch (2.54cm/in)                         //Sonar BW -- Useless for this projectvoid sonarSetup(){  pinMode(sonarPW, INPUT);}int sonarPulseWidth(){  return ((pulseIn(sonarPW, HIGH) / 147) * 2.54);}

You can download the sketch below.