Halo SPNKR Rocket Launcher Replica

Overview

Developed the embedded control software for a functional, 1:1 scale replica of the M41 SPNKR Rocket Launcher from the Halo video game franchise for my friend Jairus, from the YouTube channel Jairus of All. The system controls the rotating barrel assembly, firing animations, and haptic feedback.

Technical Architecture

• Hardware: STM32F103 (Blue Pill) Microcontroller.
• Actuation: High-torque stepper motor with FlexyStepper driver for precise barrel rotation and acceleration curves.
• Sensors: Hall-effect sensors for barrel indexing and “Lid Open” safety interlocks.
• Build System: PlatformIO / VS Code.

Key Engineering Features

• Haptic Audio: Implemented a novel feature where the stepper motor coils are driven at specific frequencies to play the Halo theme song and weapon sound effects, turning the motor itself into a speaker.
• Calibration Firmware: Wrote test code to allow the hardware to drastically reduce the time to get to full operational status.
• Kinematic Realism: Programmed custom acceleration profiles to mimic the heavy mechanical movement of the in-game weapon.

Complexity

• State Management: Handled complex state transitions (Reload -> Safety Check -> Indexing -> Firing) with custom software debouncing for reliable user input.
• Safety: Implemented hardware interrupts to immediately halt high-torque motors if the reload carriage is opened during operation.

Impact & Reach

• Viral Success: Featured on “Jairus of All” (802k subs) and “Impact Props” (1.4M subs).
• Scale: Combined views across build series and features exceed 2.8 million.
• Media:
  • Watch the Build Series (Jairus of All)
  • Watch the Feature Video (Impact Props)
• Credit: Explicitly credited for embedded engineering work (e.g., Build Series Video 4 @ 2:56).
• Demonstrates ability to deliver reliable hardware/software for high-visibility public projects.

Project Resources