How to build an Autotester

This describes the steps for making the automated water tester.  The design has slightly changed since the initial post.  The original design required printing a central stalk which all the parts attached to.  The stalk was 310mm long, which meant that a large format printer was required.  In addition, it was difficult to print it without warping.  Based on some suggestions, I redesigned the tester to use a piece of 2020 extruded aluminum as the central stalk as well as in a few other parts that were long.  The tester parts can now be printed on a printer with a 150mmx150mmx150mm build area.

The autotester is controlled through a web interface.

For convenience, I have broken the assembly into multiple parts:

  1. Overall guidance on printing the autotester 
  2. Concept of operation
  3. Putting together the mixer stand
  4. Putting together the carousel assembly
  5. Putting together the stopper assembly
  6. Putting together the plunger assembly
  7. Putting together the camera mount
  8. Putting it all together
  9. Miscellaneous Parts
  10. Electronics
  11. Software
  12. Operation

The Bill of Materials for the AutoTester Can be found here.

The STLs can be found on Thingiverse here.

The PCB design can be found here.

The software can be found here.  And the install instructions are here.

A video showing the previous prototype in operation can be found here.

Good luck and feedback on the design or the build process is welcome