Published April 29, 2026 © MIT

WRC - Wifi Rally Car

Making an FPV car controlled through wifi on a PC

IntermediateShowcase (no instructions)15

Things used in this project

Hardware components

SparkFun Dual H-Bridge motor drivers L298

LM2596 DC to DC Buck Converter

Perf Board

SG90 Micro-servo motor

BeagleBoard.org PocketBeagle

TG-05 DC Motor

Jumper wires (generic)

Toggle Switch, On-On

Wifi Module

FPV Camera

OTG receiver

Rechargeable Battery, 12 V

Ball Bearings

Software apps and online services

Microsoft VS Code

Hand tools and fabrication machines

Soldering iron (generic)

3D Printer (generic)

Story

Background

This wifi car was a project for the EDES 301 course as a part of my engineering design minor. I have been fascinated by the concept of living in a big world. FPV has recently exploded in drones and RC cars. Additionally the rise of hobbyist 3D printing has allowed others to build their own RC cars. I decided that for one, I could be one of the first to combine both a 3D printed car and an FPV system and then operate it all through wifi. A lot of my software was based on the work done by Daniel Zoch in his project where he set up the pocketbeagle as a wifi access point linked here: https://www.hackster.io/daniel-zoch/automated-pocketbeagle-wifi-access-point-057358

Given the parts that I had, I had to modify my configuration so that the pocketbeagle connected to a network (in this case a phone hotspot) and spoke to a PC connected to the same network through the hotspot. Additionally, to minimize lag on the video feed, I decided to make the camera signal transmit through radio.

Electrical

The code for this project depended on being able to get the UDP server up and then controlling components through that server. A UDP server was chosen in order to minimize any input delay between the PC and pocketbeagle even if that meant that some inputs could be dropped. The servo for steering and the motor for driving the car were controlled through both pwm and gpio signals. The specific wiring that I utilized for this project can be pictured here with color coding.

After this I added an on and off switch to the battery pack for ease of use. The hardest part of this project was getting the wifi module setup and connected to the hotspot. The high current draw required by the wifi module also lead to the pocketbeagle browning out at times.

Design

One of the things that took the longest on this project was designing the car. After many hours I compiled a full assembly. The thing is, this first design is not where my 3D designing ended. After this I added things such as the FPV camera mount and clamps on the bearings to stop them from moving.

I went through many iterations of the gear system that was used to drive the car. A key issue was generating enough torque in order to drive the car. I ended up generating 3:2 ratio bevel gears and spur gears in order to create a 9:4 gear ratio which was enough to overcome the weight and friction of the car on the ground. There are 94 total CAD files from my time prototyping and designing the final components of the car.

Building

A lot of time during the build process was spent prototyping different designs and understanding what meshed best with the physical components that I had bought.

The design kept the components in mind, in the chassis I left different grooves for different electrical components to go such as a spot for the pocketbeagle and wifi module separated from the battery and the other electronics.

To cut down the 5mm shafts that fit the bearings, I used a metal mitre saw.

When 3D printing, use the 3D printer OS slicing software with the STL files in the google folder. Some of the components may need to be drilled or sanded in order to be fit with each other. Components such as the bevel gears and spur gears need to be superglued onto the axel and motor gear in order to ensure that no slipping occurs during operation. Additionally the fit between the axle and the bearings is quite tight so make sure to use some sort of lubricant and a hammer to get the bearings in the correct spot.

A big help during this prototyping phase was stlgears.com. It allowed me to quickly get the 3d print files for all of the gears I wanted to try, allowing to experiment with helical, double helical, and different spur gears. After many hours of prototyping I had a working car!