Dirty Pool Turbidity Testing

An unfortunate chemical imbalance in our pool this past long weekend resulted in some algal growth and clouding of the water. Normally this would be cause for disappointment, given the warm weather we have been having lately. However it was a good opportunity to test out the cat-food-tin turbidity sensor. The following is the turbidity voltage data that has been collected since about 4:00 pm this afternoon:

The good news is that the chemical re-balancing that Kelly performed earlier today appears to be working. This was the state of the pool at the start of data collection (~ 4:00 pm):

At the time of this writing it is dark outside, but I'll post a picture of the (hopefully) cleared pool tomorrow morning. Other turbidity readings collected over the past week were usually around 3.6 or 3.7 V when the pool was clear. At Cap-Brulé this past weekend, the turbidity voltage was between 3.35 V and 3.5 V. That was for a moving boat however, which could possibly have some air bubbles interfering with the readings a bit.

Some new software for AMOS was also tested at Cap-Brulé. It changed how the log file was saved, in order to open/close the file for each write, ensuring no log data gets lost in the event of a crash. Also, a secondary program was created to launch the main AMOS program, and then re-launch it if necessary in the event of a crash. Since implementing these changes, no crashes have been observed, but if a crash does happen, AMOS will be ready!

Here is a picture of Hannah holding one of the new 3D printed propeller shields:

These shields are quite light and only contribute a modest amount of drag. They will hopefully protect the propellers from the worst types of entangling seaweed. The water at Cap-Brulé was relatively weed-free this weekend, so a more harsh test will be done tomorrow at Woolastook in an area that has a lot of lily pads.

EDIT: At 07:20 this morning (Sept. 05) the pool is now much more clear. The turbidity sensor is  averaging ~ 3.7 V: