Matthias' Blog

In this article I will explain the operation and construction of a pill timer that can make phone calls via a cordless telephone handset. I will explain the individual parts of the device and explain the logic that controls the pill timer and telephone. Operation of the pill timer The pill timer connects to a keypad, an LCD, and a telephone handset. when the user powers on the pill timer, they must enter the current time using the keypad. To start the timer, the user presses tha "1" key on the keypad. The pill timer determines at what times the user needs to take their pills according to a schedule that has been hard-coded into the pill timer. When it is time for the user to take a pill, the timer will initiate a call to a pre-programmed number. Once the user has picked up, it will play a recorded message. Specifically, this recorded message is "It is time for pill box number" followed by a number. Schematic and explanation gEDA schematic file Memory chip T

In this article I will present a program that can identify the most efficient angle of a solar panel, taking into account any objects that may cast a shadow on the panels. I will explain each step of the program. The source code can be found at https://github.com/mnigmann/solar Finding the sky The program takes as an input an image of a spherical projection of the surroundings, such as the image below: To identify the regions of sky, the program applies a Sobel filter, dilates the image, and applies a threshold. This causes regions where the color does not change much (such as the sky) to be black and regions where the color changes a lot to be white (such as trees, grass, buildings, etc.). For the above image: The user must then click on the regions of the image containing sky. Using the cv2.floodFill function, the program identifies the rest of the sky, as seen below: Finding the position of the sun The program calculates the position of the sun based on some formulas fr