This project involves a basic algorithm of a motion sensor stopwatch which also determines which athlete on a particular lane finished first. When the push-button is pressed, it starts the stopwatch and the buzzer sounds. Out of four infrared sensors at the end, the one which gets the HIGH signal first stops the stopwatch and the respective LED bulb glows, ultimately showing the time of the fastest athlete.
It is obvious that when two athletes finish at almost the same time, it creates ambiguity in the final decision. Thus, to save time and have a clear decision, the position monitoring idea was implemented. This system helps avoid ambiguity and ensures a clear result.
This is just a glimpse of the idea. Long-range infrared sensors can be used to make the system functional at a larger level.
I used TCRT5000 infrared sensors, which have a low range, so I made lanes approximately 4 cm wide. The sensors must be glued upright to the designated platform to ensure uniform readings.
I used Balsa wood sheets to create the platform, as they are easy to cut and allow for a neat appearance.
Below are the circuit connections for each component:
16*2 LCD Display with i2c module Connections:
SDA = A4
SCL = A5
GND = GND pin on Arduino board
VCC = 5V pin on Arduino board
TCRT5000 infrared sensor-1 Connections:
DO = Digital pin-10 on Arduino board
GND = GND pin on Arduino board
VCC = 5V pin on Arduino board
TCRT5000 infrared sensor-2 Connections:
DO = Digital pin-11 on Arduino board
GND = GND pin on Arduino board
VCC = 5V pin on Arduino board
TCRT5000 infrared sensor-3 Connections:
DO = Digital pin-7 on Arduino board
GND = GND pin on Arduino board
VCC = 5V pin on Arduino board
TCRT5000 infrared sensor-4 Connections:
DO = Digital pin-6 on Arduino board
GND = GND pin on Arduino board
VCC = 5V pin on Arduino board
LED-1 Connections:
+pin = Digital pin-2 on Arduino board
-pin = GND pin on Arduino board
LED-2 Connections:
+pin = Digital pin-3 on Arduino board
-pin = GND pin on Arduino board
LED-3 Connections:
+pin = Digital pin-4 on Arduino board
-pin = GND pin on Arduino board
LED-4 Connections:
+pin = Digital pin-5 on Arduino board
-pin = GND pin on Arduino board
Push-button-1 Connections:
pin-1 = GND pin on Arduino board
pin-2 = Digital pin-9 on Arduino board
Push-button-2 Connections:
pin-1 = 5V pin on Arduino board
pin-2 = +pin of buzzer
Both push buttons must be placed side by side, and their buttons must be glued to the same piece of wood to make a single functional button. This ensures the buzzer sounds when the push button for the timer is pressed.
When the 'single' push button is pressed, the timer starts and the time is displayed in milliseconds for high precision. When one of the infrared sensors reads a HIGH signal, the stopwatch stops, and the corresponding LED glows. If the first infrared sensor reads HIGH, no other sensor should interfere with the calculated time.
If the code doesn’t work initially, upload the code to find the address of the i2c LCD first.
Download all the code files (code and other pictures)In the drive link is a short video demonstrating how the system works. It shows the entire process of setting up and running the system with athletes.