About This Program

This Freeware program was written to help you design solar collector or wifi projects using Parabolic Reflectors. This program calculates the focal length and (x, y) coordinates for a Parabola of any diameter and depth. It can help you determine what size and shape to make your parabola very quickly.

If you would like modifications to the program to make it more useful to you, or to send feedback, you can email me here.

Thanks to Bernhard S. Müller for beta testing the program.

Download the Program

This program was written in Visual Basic 6, and should run on Window 95 or later. It requires the Visual Basic 6 Runtime files, your computer may already have them installed. I would try downloading the smaller file first and seeing if it runs. If not, delete it and download the full Windows Installation Package. This will do a standard Window Installation of this program on your computer.

• Download Parabola1.1.exe (81 kB) (does not include Visual Basic Runtime Files.)
• Download Windows Installer (1.60 MB) (extract files & run Setup.exe to install.)
• Download VB6 Source Code (85 kB)

Links

SolarTechnik.com
La Cuisson Solaire
Welcome to ReCombinant Design!
The Solar Cooking Archive Wiki

Program Notes

1.When you run the program you will see the main program window shown here. Use any units you like, as long as you use the same units for both the Depth and Diameter. I recommend using smaller units: inches instead of feet, or centimeters instead of meters, to increase the resolution of your measurements.

2. After you enter some numbers into the Diameter and Depth text boxes and click the Calculate button, the program will show you the scaled down shape of the parabola you described, and it will calculate the (x, y) coordinates of the curve of the parabola in 16 straight line segments. You can calculate the (x, y) coordinates using anywhere from 2 to 1000 segments.

3. To see what the shape and focal length would look like when the depth is increased to 18, hold down the horizontal scroll bar next to the text box and watch the parabola's shape change.

4. If you click the Save to Text File button, the program will prompt you to select a folder and enter a filename, and then it writes a file with the information you see in the text box on the right. Here's how the saved file looks when it is opened using Windows Notepad (using the Lucida Console non-proportional font where all characters have the same width so the columns line up vertically). The program will automatically suggest a filename that includes depth and diameter but you can enter any filename you like.

5. If you'd like to see the coefficients of the Equation that describes the current Parabola, use the menu choice: File > View the Coefficients. You will see a message box like this one showing you the values used in the parabola equation:

6. If you move your cursor over the image of the parabola, you will see the individual points calculated by the program: the (x, y) coordinates are shown at the bottom of the display. The point (horizontally) closest to the mouse cursor will be shown, you can see the location of each point listed in the text box.

7. There are several file output formats you can use to save the data to a file that can be read by another program like ACAD, CorelDraw, or MS Excel. You can see these menu choices under the File menu.

You can print the graphic of the parabola to a printer using the Print menu choice.

You can change the foreground and background color of the Parabola graphic using the Options menu choice.

8. If you'd like to read more about Solar Collectors and Solar Cooking Projects, or about the math behind Parabolas, click the menu choice:
File > Parabola and Solar Project Websites.
Click on a website and it will load into your default web browser automatically. Click the Hide button to view the main program form again when you're finished with the web sites. A collection of these links can be found here.