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--- beam_robotics [2009-01-12 10:14] – davegriffiths
+++ beam_robotics [2009-01-12 10:26] – davegriffiths
@@ Line 56: / Line 56: @@
 The power coming from a solar cell is pretty tiny. In order to do anything much, especially drive a motor, you need to employ some method for increasing the current from the solar panel. The commonest method in BEAM robotics is to store the energy in a capacitor and use it in bursts. This circuit is called a solar engine.
+====FLED Solar Engine====
 {{http://www.pawfal.org/dave/images/beam/solarengine.png}}
+The LED is a flashing type, and is used for detecting when the voltage across the capacitor reaches around 2v - then it turns on and trips the transistor into dumping all the power to the motor. The bigger the capacitor, the more charge it will store. This method is known as a FLED Solar engine.
 <html><embed src="http://blip.tv/play/AeXoAY_+Sw" type="application/x-shockwave-flash" width="320" height="270" allowscriptaccess="always" allowfullscreen="true"></embed> </html>
+====1381 Solar Engine====
+A more efficient method is to use a voltage regulator, such as the 1381 - unfortunately they are difficult to get hold of, and I couldn't manage to get any voltage regulators I had to work.
+====Timed Solar Engine====
+Another method is to just have a timer waiting a set time for the capacitor to charge. This can be useful if that fits the application better, but it's less efficient than the methods above, as you need some power to run the timer. I tried this with a 555 IC, but the power coming from the solar cell was insufficient to run the timing chip. It might be possible with a 7555 - the low power cmos version of the 555 timer.
 ===BEAM types===