The core difference
Arduino is a microcontroller. It runs one program at a time, has no operating system, and interacts directly with hardware pins. Raspberry Pi is a single-board computer. It runs a full Linux-based OS (typically Raspberry Pi OS), supports multitasking, network connectivity, and peripheral devices like screens, keyboards, and cameras.
This distinction determines almost everything else in the comparison. A student project that needs precise timing, direct motor control, or reliable real-time sensor reading is typically better served by Arduino. A project that needs a web interface, image processing, data logging to a database, or SSH remote access belongs on a Raspberry Pi.
Side-by-side comparison
| Criteria | Arduino Uno R3 | Raspberry Pi 4 Model B (2GB) |
|---|---|---|
| Processor | ATmega328P, 16 MHz | ARM Cortex-A72 quad-core, 1.8 GHz |
| RAM | 2 KB SRAM | 2 GB LPDDR4 |
| Storage | 32 KB Flash | MicroSD card (external) |
| Operating system | None (bare-metal) | Raspberry Pi OS (Linux) |
| Power consumption | ~50 mA at 5V | ~600 mA idle, up to 1.3A load |
| Analog inputs | 6 (10-bit ADC) | None (requires ADC add-on) |
| GPIO pins | 14 digital, 6 PWM | 40 GPIO (digital only) |
| Primary language | C/C++ (Arduino IDE) | Python, C, C++, Java, many others |
| Retail price (PLN) | ~65–90 | ~250–320 |
| Setup time for beginners | 5–15 minutes | 20–40 minutes (OS install + config) |
What Arduino handles better
Arduino's direct hardware access and predictable execution timing make it the right choice for:
- Sensor reading with tight timing requirements — ultrasonic distance sensors (HC-SR04), infrared line followers, and encoders rely on microsecond-level pulse timing. Arduino handles this reliably; Raspberry Pi, running Linux with process scheduling, introduces unpredictable latency.
- Motor control via PWM — driving DC motors through H-bridge modules or servo control via PWM works cleanly on Arduino without the timing jitter that affects Pi GPIO in Python.
- Battery-powered mobile robots — Arduino Uno draws around 50 mA; Raspberry Pi 4 draws 600 mA at idle. For a robot running on a 1500 mAh LiPo, this is the difference between 30 hours and 2.5 hours of continuous operation.
- Absolute beginners with no Linux experience — the Arduino IDE compiles and uploads a sketch in under 10 seconds. There is no terminal, no package manager, and no file system to navigate.
What Raspberry Pi handles better
Raspberry Pi's full operating system and processing power make it appropriate for:
- Computer vision — OpenCV runs on Pi OS, enabling object detection, colour tracking, and lane-following via camera. This is not feasible on Arduino.
- Web-based dashboards — students can run Flask or Node.js on a Pi to build browser-accessible robot control interfaces or data displays.
- Machine learning inference — small TensorFlow Lite or ONNX models run on Pi 4, enabling voice command recognition or gesture classification at the edge.
- Data logging and analysis — Pi can write sensor data to SQLite, CSV, or send it via MQTT to a server. Storage and processing capacity on Arduino is insufficient for sustained logging.
Common use patterns in Polish school contexts
In practice, many school projects and competition robots use both boards together: Arduino handles real-time sensor and motor work, while Raspberry Pi (or a Pi Zero) handles higher-level processing, decision-making, or a web interface. Communication between the two typically runs over a serial USB connection.
For younger students (10–13) and introductory robotics clubs, Arduino is the standard starting point — the lower price, simpler setup, and direct hardware interaction are consistently cited by instructors as advantages over starting with a Pi.
For older students working on Science Olympiad electronics categories, maker faire entries, or independent projects requiring data visualization, Raspberry Pi is more appropriate.
The question is not which board is better — it is which board matches the project's requirements. Most school robotics projects that actually move something are Arduino-first. Most projects that display, classify, or communicate something are Pi-first.
Available alternatives worth noting
Two boards occupy useful positions between Arduino and Raspberry Pi:
- BBC micro:bit v2 — a purpose-built educational board with on-board Bluetooth, accelerometer, and LED matrix. Supports MicroPython and a block-based editor. Popular in Polish primary schools. Retail: ~60–80 PLN.
- Raspberry Pi Pico — a microcontroller (not full computer) based on the RP2040 chip. Supports MicroPython and C, has 26 GPIO pins with 3 ADC inputs, and costs around 25–35 PLN. A capable Arduino alternative with better language support.
Summary
For student robotics projects in a school or extracurricular setting in Poland, Arduino Uno remains the lower-friction, lower-cost starting point. Raspberry Pi 4 is the appropriate choice when the project requires networking, vision, or general computation that exceeds what a microcontroller can provide. The two boards are complementary rather than competing, and the most capable student robots typically combine both.
Further reading: Arduino Getting Started Guide · Raspberry Pi official documentation · micro:bit getting started
