Math- anchoring

A very important aspect on my final product is going to be how I anchor this buoy. I mentioned this earlier in the report, under science. The major aspect is tension. The anchor and chain will be pulling on the buoy in order to keep it in place. It is very important that the chain is not applying any force when there is no tide, or else the buoy will be pulled under water. On the other hand, it is important that the buoy applies some force on the buoy when the tide picks up in order to stop the buoy from drifting far from its deployment site (an image of loosely anchored buoys can be seen in the picture). This means I have to calculate the depth of the deployment site, as stated above in the science section. Then I have to determine how much of the buoy will be under water with all the equipment inside the container. From here, I must calculate the height of the anchor, and subtract it from the site’s depth. The equation I will use will look something like this:
Chain length= Site’s Depth – height of anchor – length of buoy under water + (4*chain needed to extend to each outer support)
This equation will give me the final length of chain needed to anchor my final buoy. In case of a mistake, I will make sure to have a chain that extends slightly longer than my necessary calculations. I will be able to trim off any extra chain if needed, but leaves some room for mistakes.
Since I do not know what equipment will be on the buoy thus far (including test
taking equipment and solar panels), I cannot complete this calculation. A single solar panel will make a very large difference in the weight of the buoy. I have come up with this equation to ensure that I can do the calculations correctly when I am given all the final information.