Science Control Unit (SCU) - Geowissenschaften/EXCISS GitHub Wiki

Summary

This document describes the operation of the EXCISS Science Control Unit (SCU).
The SCU is part of the Microgravity Lab Unit (MLU) and triggered by the Main Control Unit (MCU) to perform scientific experiments using the Science Experiment Unit (SEU).
The SCU is implemented using a Raspberry Pi (RPi) running Raspbian.


SCU tasks

The SCU performs the following tasks after beeing started by the MCU:

  • Set up SCU working environment
  • Apply updates of O/S, SCU programs and science profiles
  • Perform science experiment
  • Process and transfer data and generate reports
  • Shut down and power off RPi

Interfaces

The SCU directly interfaces with the following components of the MLU:

  • Main Control Unit (MCU)

    • Read date and time from Real Time Clock (RTC)
    • Control charger/shaker/LEDs/ignition of Science Experiment Unit (SEU)
  • Camera of Science Experiment Unit (SEU)

    • Take stills and videos
  • USB hub (USB_A/USB_B/USB_X)

    • Read and write programs, data, and logs from and to flash memory
  • SD cards (dual-boot per PCB design)

    • Boot O/S from currently selected SD card (controlled by MCU)

Control Structure


Science Experiments


File System Layout


File Format Definitions


SCU OS Setup (Raspbian)


Open and Solved Problems