McScope

From Microwiki
Revision as of 08:05, 19 August 2019 by Mcmaster (talk | contribs)
Jump to: navigation, search

This page is about a reference DIY microscpoe control system similar to those used by John McMaster. Its intended to be a good starting place for what options might be for adding automated image capture to a microscope.

Mcscope overview thumb.png


Above: high level sample architecture. In this example one axis uses an MDrive17 and a second axis uses a generic stepper motor without integrated driver. However, in a real system you probably want X and Y to use the same motor/drive


Useful links:

Terminology:

  • Indexer: a device that generates step/direction pulses
  • Drive: power electronics for (stepper) motor
  • Beaglebone Black (BBB): embedded board with lots of accurate timing I/O
  • Machinekit: a CNC controller (indexer) distribution for BBB. Based on LinuxCNC
  • BBB Indexer (B3I) cape (PCB): allows BBB I/O to adapt to current/voltage requirements of typical drive photodiodes with convenient connections
  • BBB Indexer (B3I) system: b3i PCB + BBB assembly

Reference system, focusing on critical components:

  • Microscope
    • AmScope MU800 camera
    • MDrive17 stepper motors on XY stage
  • b3i system
    • BBB
    • Machinekit
    • B3I cape
  • T61p laptop
    • Ubuntu 16.04LTS
    • pyuscope (microscope control software)
    • touptek.ko modified for direct RGB control

Reference workflow:

  • Connect BBB over USB to host laptop
  • Host laptop: static config IP to 192.168.7.1
  • SSH -X from T61p to BBB (192.168.7.2)
    • Launch LinuxCNC software over X
    • Launch server.py RPC client (TODO: bring back automatic launch)
    • Use LinuxCNC GUI for all setup movement, not pyuscope
  • Optional: white balance camera using cal.py. Write values to microscope.json
  • Start pyuscope software
  • Select current objective (ie 20x)
  • Use LinuxCNC GUI to navigate around stage and make adjustments to level out
    • TODO: add link / suggestions how to do this
  • Use LinuxCNC GUI to navigate to upper left corner of die and in pyuscope hit "set upper left"
  • Use LinuxCNC GUI to navigate to lower right corner of die and pyuscope hit "set lower right"

Misc notes:

  • b3i default configuration is to power I/O buffers from "SYS_5V", which means external power is required. The easiest way to do this is to supply 5V to the barrel jack using a second USB to barrel jack cable