Project Members

Devin Cress
Virginia Tech Electrical Engineering (2025) dcress94@vt.edu

Alex Betz
Virginia Tech Electrical Engineering (2025) abetz01@vt.edu

Summary

The Modular Amateur Rocket Computer, or MARC, is an ARM-based flight computer for use in high-powered amateur rockets. The computer will continously monitor and log linear acceleration, rotation, altitude, and compass heading, as well as deploy recovery devices and ignite additional stage motors.

As this is a long-term project and we would like to add additional features in the future (namely telemetry), a modular design has been chosen in which multiple boards are stacked and interconnected via header pins. Five header pins will supply battery voltage, 3.3V, ground, and two I2C lines to every board in the stack, allowing new hardware additions without a complete system redesign.

The MARC will eventually be used in the high powered rocket that we are developing alongside this project - the Lima II.

Components

The initial MARC design will include the following boards:

Sensor Board

Contains the MARC's sensor suite, including accelerometer/gyrometer, magnetometer, and altimeter.

  • 1 Accelerometer/gyrometer IC - LSM6DSO32XTR
  • 1 Magnetometer IC - IIS2MDCTR
  • 1 Barometer IC - BMP390
  • 1 5-pin pass-through header

Power Board

Contains USB charging circuitry for a connected LiPo battery, a chip for measuring battery charge, and a 3.3V regulator to provide power to the board stack.

  • 1 1000mAh LiPo battery - ASR00012
  • 1 3v3 low-dropout voltage regulator - LD29080DT33R
  • 1 I2C battery gauge IC - MAX17048
  • 1 LiPo battery charge IC - MCP73831T
  • 1 MicroUSB port - 10118194
  • 1 0805 red LED
  • 1 0805 green LED
  • 1 5-pin pass-through header

Main Processor Board

The brains of MARC, this board contains the STM32 microcontroller. It will also include SRAM for temporary data storage, an SD card slot for data retreival, MOSFETS for motor and deployment charge ignition, and LEDs and a piezo buzzer for status indication.

  • 1 STM32F401RET7
  • 1 SRAM IC
  • 1 MicroSD card slot - 104031-0811
  • 3 n-channel MOSFETs
  • 3 screw headers
  • 1 piezo buzzer - CMI-9705-0380-SMT-TR
  • 5 dip switches
  • 1 5-pin pass-through header