Autonomous Field Following Robot
Designed a battery-powered autonomous robot that detects and follows the changing magnetic field generated by a guide wire with AC current from a function generator. Notable hardware functionalities include an autonomous object detection system with automatic braking, DC Motor control through Pulse Width Modulation, magnetic field detection through LC Tank Circuits, and a wireless remote controller using UART to transmit and receive commands to/from our robot.
Hardware Design Lead · UBC ELEC291 · Electrical · 2026-01-01 – 2026-04-30
Problem
Our team needed to design and test a fully functional field-following autonomous robot with the tools and parts given to us. Numerous challenges, such as field detection, motor control, microcontroller implementation, and remote controller implementation, were solved within the 3 weeks given.
Architecture & implementation
Designed and implemented two discrete Half-Bridge MOSFET Circuits, connected them to our DC Motors and STM32 Microcontroller to be controlled using Pulse Width Modulation (PWM). Implemented optoisolators to prevent signal noise from our DC motors propagating throughout our circuit. Soldered and assembled three tuned LC Tank Circuits with their respective Non-Inverting Amplifiers and Peak-Detector Circuits to send magnetic field data and position to our STM32 Microcontroller's ADC System. Installed and used the Universal Asynchronous Receiver Transmitter (UART) Communication Protocol to send and receive commands to/from our robot to switch between autonomous field following mode and manual driving mode through a decoded joystick. Including proportional-like control by adjusting DC Motor speed through increasing/decreasing PWM cycles for more fluid control by the joystick. Used the Inter Integrated Circuit (I2C) communication protocol to implement a Time of Flight (VL53L0X) module to achieve an automatic collision braking system for our autonomous robot. Managed power rail design and ensured our microcontroller's power supply was isolated from our motor power. Preventing overvoltage and maintained functionality. Placed decoupling capacitors to maintain signal integrity throughout the circuits. Efficiently troubleshot all circuit/hardware errors and malfunctions on the autonomous robot.
Results
A fully functional autonomous robot that follows a magnetic field generated by a guide wire. Including intersection detection and predetermined turns (Right/Left/Straight) at each intersection.
Project Media
