Arduino Vending Integration Support

$10-30 USD

In Progress

Posted 19 days ago

$10-30 USD

Paid on delivery

I’ve put together a prototype smart vending machine around an Arduino UNO that authenticates users with an RC522 RFID reader, lets them pick Snickers or Skittles on a 4 × 4 keypad, and drives stepper motors to release the selected treat. Each part works on its own, yet when I run the full sketch the system freezes, tags go unread, or the wrong motor spins. I don’t have a complete wiring diagram yet, so one of the first tasks will be helping me draft a clear schematic before we dive into the code. From there, I need comprehensive guidance: • Debugging the existing sketch so RFID login, keypad input, and AccelStepper control cooperate without blocking the loop • Advising on clean wiring, power distribution, and noise suppression to keep the motors from browning-out the UNO • Recommending performance optimisations—state machines, debouncing, timer interrupts—so the dispenser stays responsive Deliverables 1. A revised, well-commented Arduino sketch ready to upload 2. A simple, shareable wiring diagram (Fritzing, Eagle, or clear SVG) 3. A brief change log explaining what you altered and why, so I can learn for future iterations Acceptance criteria • Valid RFID tags always grant access; unknown tags are rejected • Keypad registers every keypress without ghosting • Correct stepper turns the right number of steps and then stops • Main loop remains responsive during any motor activity My starting budget is $5, but I’m happy to negotiate upward for experienced, teach-as-you-go assistance that gets the machine dispensing reliably. If you’ve tamed RC522 readers, membrane keypads, and steppers before, I’d love to work with you.

Project ID: 40405888

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Remote project

Active 18 days ago

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@amelectronics

I am a skilled and reliable Embedded Systems Engineer with over 6 years of hands-on experience in Arduino, ESP32/ESP8266, and microcontroller-based development. I specialize in designing efficient, stable, and scalable embedded solutions, turning ideas into fully functional hardware-software systems. I have a strong background in electronics, sensors, communication protocols (UART, I2C, SPI, MQTT, WiFi, BLE), and real-time embedded systems. My development approach focuses on clean, well-structured, and well-documented firmware, ensuring long-term reliability and easy maintenance. I also provide thorough testing, debugging, and performance optimization, including power efficiency improvements where required. I am a detail-oriented engineer with strong problem-solving skills and extensive experience in hardware debugging and firmware optimization. Beyond technical expertise, I value clear communication, meeting deadlines, and maintaining high client satisfaction. I work closely with clients to fully understand project requirements and deliver high-quality results. Pricing is flexible and can be discussed based on project scope and complexity. I am open to both short-term and long-term projects. Let’s work together to build a professional, reliable, and efficient embedded system for your needs.

$35 USD in 7 days

4.8

(86 reviews)

7.4

4 freelancers are bidding on average $41 USD for this job

@Webslinger01

I have Arduino in stock and hands-on experience integrating multiple peripherals — including a home automation system with Arduino, RFID, relay control, and multi-device coordination. RC522, membrane keypads, and AccelStepper are components I've worked with before. Your freeze is almost certainly a blocking loop issue — AccelStepper's runToPosition() or delay() calls stalling the RC522 SPI reads and keypad polling. The fix is a non-blocking state machine where each peripheral gets checked every loop iteration without any one of them holding up the others. I will deliver: • Revised sketch: non-blocking state machine for RFID auth → keypad selection → stepper dispatch, clean SPI timing, keypad debounce, correct AccelStepper run() placement • Clear wiring diagram (Fritzing or SVG) covering power distribution, motor driver decoupling, and noise suppression to prevent UNO brownouts • Commented change log explaining every fix so you understand what changed and why Delivery in 3 days. Can you share your current sketch and a photo of your wiring so I can identify the exact blocking call before we start?

$60 USD in 3 days

5.0

(4 reviews)

3.2

@soniaer987

Hi, I have worked on Arduino-based vending machine projects before, including RFID authentication, keypad input, and stepper motor control, so this is a familiar problem set for me. The freezing you are seeing is almost certainly a blocking call somewhere in the loop, likely in the RFID polling or a delay-based stepper sequence. These three subsystems need to run cooperatively using a state machine, not sequentially. Here is what I will deliver: - A clean wiring schematic covering the RC522, 4x4 keypad, stepper drivers, and power distribution with noise suppression for the motors - A revised, well-commented Arduino sketch using a non-blocking state machine so RFID, keypad, and AccelStepper all cooperate without freezing the loop - Proper debouncing for the keypad and interrupt-safe RFID handling - A short change log explaining every fix so you understand what changed and why All acceptance criteria you listed will be met: valid tags grant access, unknown tags are rejected, correct motor spins the right steps and stops, and the loop stays responsive throughout. Let me know if you want to move forward. Timeline 3 days Thank you.

$50 USD in 3 days