# Four Motors, Two Drivers: The 4WD Arduino Robot Kit

> Four TT motors, two L298N drivers and ultrasonic avoidance on a ₹1,320 4WD chassis — a rough-ground robot platform and a lesson in power-noise discipline.

[HTML version](https://soldr.ai/blog/four-motors-two-drivers-the-4wd-arduino-robot-kit)

23 August 2026 · Bharat Raj · [originally published on Compoden](https://compoden.com/blogs/guides/four-motors-two-drivers-the-4wd-arduino-robot-kit)

The [4WD Arduino Robot Kit with Ultrasonic Avoidance](https://compoden.com/products/4wd-arduino-robot-kit-with-ultrasonic-avoidance) (₹1,320) builds a four-wheel-drive robot that handles what makes 2WD builds give up: gravel, sand, dusty workshop floors and uneven ground. Two L298N motor drivers power four TT gear motors — each side commanded independently over PWM — while a front-mounted HC-SR04 ultrasonic sensor gives it autonomous obstacle avoidance. **It is an Intermediate kit, a 5–6 hour build with no soldering, and its real value is as a platform: once the chassis drives, it becomes the base for line-following, remote control or maze-solving — whatever you program next.** At ₹1,320 it is also one of the cheapest routes to a serious, competition-capable drive base in our range.

## What's in the box
Arduino Uno R3, one HC-SR04 ultrasonic sensor, two L298N motor drivers, four TT gear motors, a 4WD chassis, two 18650 cells with holder, 10kΩ resistors, eight 1N4007 flyback diodes, four 100µF 16V capacitors, and 30 male-male jumper wires. The diodes and capacitors are not filler — four motors switching on one battery pack generate real electrical noise, and this kit teaches you to suppress it properly. Connections use screw terminals and jumper wires; the only tool-work beyond a screwdriver is stripping the battery holder leads for the terminal blocks.

## What you'll learn

- **PWM speed control across four motors** — commanding each side of the chassis independently for smooth acceleration and sharp pivot turns.

- **Dual motor-driver wiring** — splitting four motors across two L298Ns and keeping the logic and power grounds honest.

- **Ultrasonic obstacle avoidance** — turning HC-SR04 distance readings into steering decisions.

- **Power distribution debugging** — using flyback diodes and capacitors to stop motor noise from resetting your Arduino, a skill every larger robot demands.

## The build, honestly
The chassis and motor mounting are straightforward; the honest difficulty is wiring discipline. Eight motor terminals, two drivers and one battery pack means the classic failure mode is a robot that veers, stutters or resets — and the cause is almost always a swapped motor polarity, a marginal ground, or missing noise suppression rather than your code. The kit anticipates this: the capacitors and diodes exist to be used, and calibrating per-side PWM in software to make four not-quite-identical motors drive straight is part of the intended learning, not a flaw. Give the power wiring the same care you give the code and the 5–6 hour estimate is realistic.

## Who it's for — and who should skip it
Ideal for CBSE Class 11–12 students building a first differential-drive robot for exhibitions or ATL lab projects, and for engineering students who need a ready-to-code 4WD base for hackathon-style autonomous navigation challenges. Makerspace regulars who keep reinventing chassis from scratch will appreciate a pre-matched platform.
Skip it if this is your very first build — the two-driver wiring doubles the places a beginner can go wrong. Our Obstacle Avoiding Robot Kit teaches the same avoidance logic on a simpler 2WD base with a servo-swept sensor, and the Sumo Robot Kit is the budget entry to driving robots. At the other end, if what you actually crave is legged locomotion or vision, the Hexapod Robot Kit and Vision Tracker Kit are the deeper waters.

## FAQ

### Can it follow a line instead of avoiding obstacles?
Yes — the motor-control code is modular. Add a line-sensor array (not included) and modify the sketch to detect and follow a tape line; the AI companion guides the change.

### Why might the motors run at slightly different speeds?
TT gear motors vary slightly unit to unit. PWM lets you calibrate each side in software, and the included capacitors and flyback diodes reduce the electrical noise that makes response inconsistent.

### Is soldering required?
No. Everything connects with screw terminals or jumper wires; you only strip the battery holder wires to fit the terminal blocks.
The kit arrives pre-loaded in Soldr, our AI build assistant, which generates the dual-driver wiring plan, the firmware and the troubleshooting steps for this exact chassis.