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Energy from Natural Resources => solar systems homemade and commercial => Topic started by: joegatt on March 11, 2009, 06:09:49 PM

Title: Meccano Heliostat for testing
Post by: joegatt on March 11, 2009, 06:09:49 PM
A small heliostat can be used for a solar kettle, or for driving a small stirling engine or thermopile.

This Mini Heliostat uses shiny hard disk platters for its concentrator.  Meccano is good for prototyping, but this motor is too fast for solar tracking. A stepper motor seems better suited for the job. My first tracking tests can be controlled by PC. A series of carefully timed nudges should keep the concentrator at the correct azimuth. For a stationary target, the mirror has to bisect the angle between the sun and the target so its angular velocity will be half that of the sun.

A final version should track the sun with photo-sensors.


Oh! ... and you can see this swivel at:

http://www.youtube.com/watch?v=uuBkbK5yP7k

Regards
Joseph Gatt

Title: Re: Meccano Heliostat for testing
Post by: hansvonlieven on March 12, 2009, 02:18:54 AM
Good on you Joseph.

For many years I have used Meccano to prototype new ideas and to test the validity of some postulate or other. It is a pity most people see the Meccano sets as something purely for kids. When Frank Hornby invented the Meccano system in 1901 his objective was to teach kids physics and mechanics. Very soon serious inventors and engineers saw this as a cheap and versatile way to prototype almost anything mechanical.

These days the Meccano system is seen as a children's toy. A shame really because with a couple of hundered dollars worth of parts you can build and test many things cheaply because you can use the parts over and over again in new projects. The versatility of Meccano is legion. Frank Hornby was a very talented and successful engineer and his ideas, from toy trains to Meccano, have stood the test of time.

Hans von Lieven
Title: Re: Meccano Heliostat for testing
Post by: joegatt on April 02, 2009, 04:16:24 PM
Yesss! A stepper motor offers a much better control of the heliostat alignment.
All I need now is some feedback to compensate for when a gust of wind pushes the concentrator off course.

Now, where will I position the photosensors ... ?


Regards
Joseph