From Robogardens via hackster.io:

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

Read more

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