Raspberry Pi 4 Model B 4GB RAM

The Raspberry Pi 4 is the gold standard single-board computer for IoT gateways, home automation servers, and robotics brain units. The quad-core Cortex-A72 at 1.5GHz with 4GB RAM runs full desktop Linux with enough headroom for complex applications.

As an IoT gateway, it excels at aggregating data from multiple sensors via GPIO, I2C, SPI, and UART, then processing and forwarding via WiFi, Ethernet, or Bluetooth. Running Node-RED, MQTT brokers, or custom Python scripts is effortless.

For robotics, the Pi 4 handles computer vision (OpenCV), path planning, SLAM, and high-level decision-making while delegating real-time motor control to an Arduino or ESP32 co-processor. The USB 3.0 ports enable fast data transfer from cameras and LiDAR units.

The 40-pin GPIO header provides all the familiar interfaces plus hardware PWM for servo control. The official Raspberry Pi Camera Module connects via CSI for low-latency video capture.

Power consumption is 3-7W depending on load, making it viable for battery-powered applications with appropriate power management. USB-C power delivery is more reliable than the Pi 3's micro-USB.