Wacky racers

Wacky Racers - High-Speed RC System Integration

Role: Embedded Systems & PCB Designer

Context: 2025 Mechatronics Design Project | University of Canterbury

Team: 4-Member Collaborative Engineering Team

Executive Summary

Engineered a high-performance radio-controlled vehicle from the ground up, focusing on a custom Altium-designed PCB and low-latency wireless communication. The project centered on creating a robust hardware-software interface to manage motor control and sensor feedback in a competitive racing environment.

Key Technical Challenges

Signal Integrity: Maintaining a stable connection between the controller and the racer in a high-interference environment (multiple teams competing simultaneously).
Power Management: Balancing high current draw for the drive motors with the sensitive 3.3V/5V logic required for the microcontroller and radio modules.

The Solutions

1. Custom PCB Architecture (Altium Designer)

Layout: Developed a multi-layer PCB to house the microcontroller, motor drivers, and power regulation.
Reliability: Implemented proper grounding planes and decoupling capacitors to minimize electrical noise from the high-RPM brushed/brushless motors.
Diagnostics: Integrated onboard LEDs and test points for real-time hardware debugging during the testing phase.

2. Wireless Communication (nRF24 Interface)

Protocol: Utilized nRF24 radio modules to establish a 2.4GHz link between the handheld controller and the vehicle.
Firmware: Programmed a custom communication packet structure to minimize latency, ensuring near-instantaneous throttle and steering response.
Interference Mitigation: Implemented channel-changing switches to ensure the racer remained responsive even when other teams were broadcasting on similar frequencies.

Results & Impact

Reliability: Achieved 100% uptime during competition heats with zero radio dropouts.
Performance: Successfully navigated the technical course, demonstrating the effectiveness of the custom Altium hardware over generic "off-the-shelf" solutions.
Teamwork: Coordinated with three other engineers to integrate the communication from the "hat" team which controlled the racer effectively.

Technical Toolkit

Software: Altium Designer (PCB), C/C++ (Embedded Programming), SolidWorks (Chassis Integration).
Hardware: nRF24L01+ Radio Modules, Microcontrollers, L298N/Custom H-Bridge Drivers, LiPo Power Systems.