Underwater Data Collector

The water layers in most large lakes is mixed throughout the year by convection currents. However, the water layers in the deep end of Ballston Lake, about 130 feet deep, has not mixed for thousands of years. With such an interesting lake so close the Union College geology department would like to conduct a long term (ten years) study. At this time there is no commercially available equipment for such a study. In my talk I will be presenting the design and implementation of a machine that will collect the necessary data. The machine sits on the bottom of the lake and raises and lowers a floating sensor package a foot at a time measuring redux, salinity, PH, and temperature. I will describe my testing to date, problems encountered, design modifications made as a result of the testing, and the work still to be done before being installed in the lake. In order for the machine to perform properly the sensor package must move smoothly through the water at a constant speed. Speed control has been implemented using a proportional-integral-derivative (PID) controller which will be described. The completion of this machine will provide a valuable tool for Union College students and faculty to perform deep lake studies at Ballston Lake and beyond.