Sentinel Data Logger (SDL)

Design Goal

SDL is designed to act as a rocket data logger, tracking pressure, acceleration , rotation, and magnetic fields. This version lacks both GPS and a radio link, but an expansion port is planned to allow later installation of both features.

It also has both a micro SD card (post flight bulk logging) and SPI flash chip (in flight logging).

Active Development

While I will do my best to keep this page updated, this project will be going through many changes in the next month or so, and as a result it will likely fall behind actual changes. The blog posts below will be the most up to date source of information on this project.

Posts

Sentinel: Component Selection

STM32G474 Microcontroller The MCU of the SDL board is an STM32G474, chosen for its extensive peripheral set and processing headroom. With multiple SPI and I²C interfaces, DMA support, and high clock speed, it can handle several sensor streams simultaneously while maintaining precise timestamping for logged data. The STM32 ecosystem and tooling also make firmware development and debugging straightforward during early prototyping. ICM-42670-P BMI088 Multiple IMUs (BMI088 + ICM

Sentinel: Early Dev

The Sentinel Data Logger (SDL) began as a compact avionics platform designed to capture high-resolution flight data during experimental rocket launches. Early in development, the focus was on building a robust hardware foundation capable of recording multiple synchronized sensor streams while remaining reliable in the harsh conditions of rocket flight. The board integrates an STM32-based microcontroller with several onboard sensors—including inertial measurement units and bar