Vending Machine With Coins and Online Payments Support Using Arduino

This is a vending machine model that is designed to accept various coins, online forms of payment like UPI and wallets(ex. Google Pay,PayTM, PhonePe, Amazon Pay etc). Nowadays, People want to avoid the hassle of carrying change and this is where online payment support is useful.

It was actually my final year engineering project that was completed but was not presented due to the Covid-19 pandemic disrupting everything. I am extremely sorry for the badly recorded videos as I never got to make a proper demonstration.

This machine only has 3 slots for storing products as it was a proof of concept, however there are motor shields for arduino that can support dozens of motors. The cashless mode is really helpful feature to have in this pandemic to reduce risk of transmission.

1. Coin acceptor:

First, we connected a 12V supply to the coin acceptor and programmed the number of coins it would support (the CS616 is able to support 6 coins but we programmed 3 which are 2Rs,5Rs,10Rs), the number of pulses that each coin would generate and then we inserted 15 samples of the coin to have high coin acceptor accuracy.

Then we interfaced the coin acceptor with Arduino and programmed it to recognize a coin based on the number of pulses that we received by the Arduino input pins.

2. GSM module:

We connect the GSM module with Arduino and program it to receive and parse payment sms notifications. The amount received gets extracted and displayed on the screen.

3. DC motors:

We connected the motors on a motor shield and mounted it on Arduino. Then we program the motor inputs like motor rotation direction, ON time for the motor to rotate the spiral mechanism just enough to dispatch one unit of product and not more.

4: LCD display:

we mount the LCD on the i2c module and interface it with Arduino.

5. LEDs and SPST:

We simply interfaced SPST switch and 3 LEDs connected in parallel.

The machine now complete.

1. First we test the idle condition of the machine.

2. Then we test the coin payment mode of the vending machine by paying the machine with different coins and verifying that the correct product is delivered, LCD displays proper amount, and LEDs highlight the correct product.

3. Then we test the Online mode of the machine by paying the machine with UPI multiple times with different values and checking the product is correctly delivered, LCD displays the proper amount, and LEDs highlight the correct product.