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Mechanical Filtering of Multiline Control & Power Signals

There are two superposed signals on the lines of a power kite; the control input used to steer and the power output that results. A control-bar separates the two signals, but this is not an optimal method for most AWECS design.

KiteLab has a simple new method for kite control input to pass through a surging power-lever. The attached image file (jpg format) shows the initial "folktoy" prototype that works well.

Note the highly optimal lever set-up showing "short-stroke" downwind displacement. A follow-on version will add a little control-bar on the lever root, actuated by the new pulley-lines.

FairIP/CoopIP                       ~Dave Santos            September 6, 2010        M2121


The heart of it is a pulley spool spun by control lines rigged for constant length whatever the power-lever does. Another set of lines on the same spool run to a multi-line kite. Power strokes act on the spool axle, which is also the power lever. A slider on the power lever allows its leverage to be tuned to wind & kite. The power lever drives a cord around a belt-drive generator capstan against a spring-retract (key-chain mech). The sinusoidal power output is rectified by blocking diodes & smoothed by a big capacitor (not shown).

The core mechanism is inspired by the Egyptian Bow-Drill & the rigging of aircraft & tall-ship controls. Flying piloted power-kites is just one aspect of the idea. An exciting super-simple use of this mechanism is for an AoA control/power cycle that drives the lever in sustained self-oscillation.

Anyone can build these things...


Comment and development of this topic will be occurring here.       
All, send notes, drawings, and photographs!

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Commentary is welcome:

  • Could we get a description of what the various parts do, please?      Bob
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