CYCLE TO FAILURE

Mission

Create a closed loop benchtop system to run multiple configurations of components through a rigorous cycle while left unattended until components reach a state of failure.

Elements

(1) Vacuum Pump

(2) Arduino microcontroller w/ SD card shield

(3) Multiple sets of different electromechanical components

(4) Suction Canister

(5) Water reservoir

(6) 12V Power Supply

(7) Relay

(8) Lots of tubing & wire

(9) 12V Water Pump

Details

In the search for the most suitable components at the best price point, a head to head comparison needed to be completed. However, the only way to truly test these components was to ensure that the test was representative of the product cycle. Rather than sit and watch the exciting show of water flow back and forth through a closed loop system for hours and hours, I decided to design and fabricate a benchtop system that would help automate the process.

The main trick was integrating all the necessary components in a closed loop and trusting it (and myself) enough to let it run overnight and collect data while I was busy counting sheep.

There were certain things that needed to come together to complete this test including:

Ensuring all connections are air tight
Providing a source of water, a canister to deposit water into, and a pump to recycle the water through the system
Writing a program for the Arduino to run components through multiple unique sequences on a loop
Collecting data on each component
Building in safety stops including auto shutdowns if enough components in question failed
Turning a vacuum pump on and off (required large relay to allow the Arduino to tell the AC powered Vacuum Pump to turn on and off)
Bleeding vacuum and return to atmospheric pressure

After lots of iterations, code updates, and frustrating air leaks, the system was up and running. Multiple trials were completed during normal work hours to prove out the efficacy, and finally multiple system runs were completed overnight while gathering lots and lots of data. In the end, the data gathered provided ample information as to which components suited the system better and would last long enough for a procedure. Additionally, we gained extra information about how the system would act under different pressure conditions as a bonus, which led to further explorations that proved helpful.