I have built a Lap timer for my track car (Tamiya Mini4wd in case you know what it is) , I used
- Arduino Nano / Arduino Pro Mini
- 128x64 OLED display
- FC-51 IR Obstacle Sensor
- Push Button for Reset
Attached the Code
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
Adafruit_SSD1306 display(128, 64);
#define button 9 //Button on Pin 9
#define IR 2 //IR sensor on Pin 2
int timerMode = 0;
long startTime;
double lapTime = 0;
void setup() {
Serial.begin(9600);
display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
display.clearDisplay();
display.setTextColor(WHITE);
display.setRotation(0);
display.setTextWrap(false);
display.dim(0);
pinMode(button, INPUT_PULLUP);
pinMode(IR, INPUT_PULLUP);
pinMode(2, INPUT);
digitalWrite(2, HIGH);
pinMode(9, INPUT);
digitalWrite(9, HIGH);
}
void loop() {
char string[10];
display.clearDisplay();
display.setTextSize(2);
display.setCursor(0, 0);
display.println("Lap Time");
if (digitalRead(IR) == LOW){
startTime = millis();
timerMode++;
delay(200);
}
if (timerMode == 1){
display.setCursor(0, 20);
lapTime =((millis() - startTime) / 1000.0);
display.println(lapTime);
}
if (timerMode > 1){
display.setCursor(0,40);
display.println(lapTime);
}
if (digitalRead(button) == LOW){ //Reset Button trigger
timerMode = 0;
}
display.display();
}
My build is working as design,
- Wait for the sensor to be triggered and start the timer count
- If the Sensor sense the second Trigger, the timer stop and print the time
- Reset Button reset the timer
My Issue is that when the car passes the sensor too quickly, it seems the sensor does not trigger Start or Stop of the timer. I can see the obstacle LED flash when the object pass the sensor, but sin many cases (over 70% of time) the Timer either NOT Start or Doesn’t Stop.
I have adjusted the range and the position is constant and stable, and as mentioned the sensor obstacle LED does flash. Any idea how I may improve the responsiveness between the Sensor and the Arduino??