Overview

The Arduino based RC (rather IR) operated toy car is a simple motor-controller circuit housed inside a metal chasis, which can interpret IR signals from a TV remote.
The toy car is made almost completely of scrap materials and components. It's orange frame is actually a broken geometry box, and even the Arduino inside is an old board whose USB port had come off.
The IR receiver was sourced from a cheap malfunctioning audio device destined to end up in an e-waste bin, and the DC motor was taken from an old toy.
Finally, the TV remote itself was of an old STB and not in use.
Even with these misfit components the aim was to create a coherent and somewhat decent looking car.

Tool Used

Arduino (RedBoard)Microcontoller

Arduino IDEText Editor & Compiler

Arduino ISPSketch to Program Over ISCP Using Another Arduino

Hot Glue GunFixing Motor and Servo

Zero-PCBPlatform for Motor-Controller Circuit

Soldering IronWorking on The Zero-PCB

Approach

I started this project on a breadboard and with an Arduino that had a working USB port.
Following a guide to build a motor controller using a diode and resistors, I layed out the circuit on the breadboard using jumper wires.
Once the motor circuit worked, I added a servo and the IR reciever to the board.
To reduce the size of the circuit, I decided to solder the components on a Zero-PCB. As I did not want to permanently use the reciever, motor and the servo in this project, I added header pins which could connect to jumper wires.
Also, I had an unused Arduino with a broken USB port which I thought would be sufficient as the car wont be connected to the computer except for while programming. So, to program it I used the other Arduino and the ISP sketch which allowed me to upload code directly without using USB Serial.
At this stage it was still spread out on a table and only after I confirmed all functions were working, did I start to make a cardboard frame.
The cardboard version lasted for exactly one day of testing, and quickly fell apart. It was time to find a more rigid solution. I did think of designing and 3D printing a model, but then saw a broken metal box lying around which looked perfect for the job. With some hot-glue and double sided tape, I affixed the components, and did minimal cable management.

Learnings

This project gave me insight into how motor controllers work, and was my first time working on a Zero-PCB. I gained valuable experience soldering thru-hole with flux (and desoldering with a solder sucker, as I made quite a mess from time to time)

Next Steps

I would like to explore PCB designing and printing to minimise messy solder work and build more robust projects.
The car could also have many other sensors (ultrasonic, camera etc.) to facillitate autonomous navigation.
It would be interesting to explore other mechanisms for wheel turning, including four-wheel drive.