Before buying a single component, decide what your robot should do. This is the most important decision in the process — it determines every part you'll need and how complex the build gets.

For a first build, we strongly recommend a wheeled ground robot. It's the easiest to assemble, the easiest to program, and the most forgiving when things go wrong. It can navigate a room, follow a line, avoid obstacles, or just drive around under remote control.

Once you're comfortable with a wheeled robot, you can graduate to robotic arms, drones, or walking robots — all of which use the same fundamental building blocks covered in this guide.

Below are all the components you need to build a basic wheeled robot. Every part is in stock and ships from our warehouse within 24 hours. Click any card to go directly to its product page.

You likely have most of these already. None of them need to be expensive — this is a prototype build, not a production line.

You'll need a USB-A to USB-B cable to upload code to the Arduino, a small Phillips screwdriver for the chassis assembly, and a multimeter to verify voltages before powering on for the first time. A soldering iron is optional — the breadboard and jumper wires handle all connections without it. A laptop running the free Arduino IDE handles all the programming.

Follow these steps in order. Each one builds on the previous. Don't skip ahead — it's much harder to diagnose a problem when multiple subsystems are connected at once.

Before connecting the battery, use your multimeter to confirm there's no short between the +V and GND rails on the breadboard. Once you're confident everything is correct, connect the battery and upload the starter sketch to the Arduino via USB.

The robot should drive forward for 2 seconds, stop, spin 90°, then repeat the sequence in a loop. If both wheels spin the wrong direction, swap the motor wires at the L298N. If only one wheel is wrong, swap just that motor's pair.

Once basic motion is confirmed, modify the sketch to read the ultrasonic sensor — for example, stop and turn if the sensor reads less than 20 cm. This is the foundation of autonomous navigation.

Robot doesn't move at all: Check that the battery is charged and properly connected. Verify the Arduino's power LED is on. Confirm ENA and ENB are wired — without these the motors are disabled regardless of what the code sends.

One motor spins, the other doesn't: Test the non-working motor by connecting it directly to a 5V source. If it spins, the issue is wiring or code. If it doesn't spin, the motor may be faulty — contact us for a free replacement within 30 days of purchase.

Bluetooth won't pair: The HC-05's default pairing code is 1234 or 0000. Make sure the module's LED is blinking (not solid) before trying to pair — a solid LED means it's already connected to another device.

Ultrasonic sensor returns garbage values: This almost always means the TRIG and ECHO pins are swapped in the wiring. Double-check your connections against the table in Step 4 above.

Arduino resets randomly while driving: This is a power issue. The motors draw a current spike when they start, which can briefly drop voltage to the Arduino. Add a 100µF capacitor across the motor driver's power input to smooth it out — available from our capacitor kit.

Once your robot is running reliably, a whole upgrade path opens up. Add a servo-mounted sensor bracket so the ultrasonic sensor can pan and scan a wider arc. Swap in an RPLidar A1 for full 360° mapping. Add a Raspberry Pi 5 alongside the Arduino to run computer vision and autonomous path planning.

For robotics enthusiasts who want to go further, our Robotic Arm Starter Kit covers servo-driven articulated builds, and our Drone Build Kit takes the same electronics fundamentals into the air.

Every component you'll ever need for those builds is in our store — and the same principles you learned here (power, control, sensing, actuation) apply to every robot you'll ever build.