Monday, November 25, 2013

Weather Station continued

I wanted to add a solar radiation sensor to my weather station but I didn't want it $160 worth like the one from Davis Instruments. I don't need that kind of accuracy, I just want to know how cloudy it is. Then I saw a light sensor on Adafruit that cost four bucks. It had the advantage that it was logarithmic so it could handle big swings in the amount of light it was measuring.
I was thinking about how to protect it from the weather and found a test tube in one of my junk boxes. It was the right diameter so I cut the end off and voilĂ !, a perfect little glass cover.

I was then considering the mathematical adjustments to make in the readings based on the fact that the angle between the sensor and the sun changes throughout the day and throughout the year. I mentioned these ruminations to my brother Jim, and he suggested that I just etch the glass so it is "frosted" and thus the light will be dispersed more-or-less evenly no matter where the sun is. I thought that was worth a try. I bought some etchant, but due to the fact that glass in the test tube was specially treated, the acid had no effect. Therefore I resorted to the old fashioned way and just took some emery paper and sanded it. 

Next I made a mount for it, embedded it in silicone, and angled it slightly toward the south. Once that was dry I fastened it to the mast holding the anemometer and rain gauge.

I plan to watch the data for the next few weeks to see how it responds to various levels of sunshine at different times of the day and see whether I need to make any adjustments.

Saturday, November 16, 2013

2001: A Space Odyssey, the Weather, and Web Programming

In 1968 I saw the film 2001: A Space Odyssey and one part of it, in particular, stuck in my mind. Around the spaceship were screens that would cycle through tables and graphs of various operating parameters of the ship. Since then I've carried the idea that it would be interesting if I could have these types of displays in my house, showing information on what was going on as far as the various systems in the house and the environment around it.

A few years ago I bought a Davis Instruments Vantage Pro2 Weather Station. My brother Jim has always been interested in weather, and my sister Monica took a course in weather forecasting when she was in college and gave me a copy of some of the handouts from that course at the time. I guess I caught the interest from them. Well, I had the weather station set up at my house in Chicago but I took it down when I moved to Asia. Now that I'm retired and living in Florida I set it up again. It gave me the idea that this could be one of the sources for data for the "2001" displays.

My idea was to create a screensaver that I would put on each of the computers around the house so that when they weren't being used they would start cycling through the various graphs and tables. I thought the best way to do that was with web pages, but I didn't know anything about web programming. Fortunately my nephew Matt did. I got a single board Linux computer and dove in. I then realized how steep a learning curve there was. The little UNIX knowledge I had was from twenty years ago, but worse than that, it wasn't just UNIX I needed. I had to learn at least a little something about HTML, JavaScript, CSS, PHP, and SQL. Every time I got stuck though, Matt was able to bail me out.

Well the webpages are finally working, and I have been saving weather data every five minutes since May, 2013 (with some hiccups) and so I have included some screen shots.

Now I just need to turn them into a screensaver and phase I will be complete.

Further Work

Besides adding another sensor or two to the weather station I want to measure things like my electricity, gas, and water usage, including monitoring the performance of the pool equipment and HVAC, and maybe even things like lp gas and carbon monoxide sensors. But at least now I have a platform on which to build.

Wednesday, November 6, 2013

Orange Sorter for Historic Spanish Point

My wife volunteers at Historic Spanish Point in Osprey Florida. It is a reserve that was part of the estate of Bertha Palmer, a significant figure in the development of the west coast of Florida, and someone with strong links to Chicago as well.

They have a reconstruction of a device that was used to sort by size the oranges that were grown there. Below are a couple of pictures. As you can likely see, the oranges are dumped in at the upper end. As they roll down the inclined top they fall into the gap between the boards that form the top. However, since the boards are closer together near the top of the "hill", and farther apart toward the bottom, the oranges fall through into the various crates based on size.

Jane Glennan is the Outreach Coordinator at Historic Spanish Point. She asked me if I would make a model of the orange sorter that she could use when she goes out and makes presentations on Historic Spanish Point to schools and other groups. Here is my miniature version. It is about 15 inches long, and is designed to sort three different sizes of wooden balls.

Below is the completed model. Jane supplied the little crates and decorated the wooden balls as faux oranges.