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Unread 27-12-2007, 15:28
Steve_Alaniz Steve_Alaniz is offline
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Re: Gear Tooth Sensor

Ah! I see what you are saying... you kill power but the bot still rolls. Well ok you have to "remember" which direction you were rolling and allow the bot to come to a complete stop... before changing direction with a single GTS. Yes in that case Quad is preferable.
But probably not a problem with something like positioning an arm.
In any case... this is still a "dead reckoning" scheme so it's an approximation anyway. (If it were easy it wouldn't be worth doing. )

In an aside... to obtain Quad with GTS... one suggestion has been that :
1) using a gear with an odd number of teeth.
2) using two GTS
3) IF you carefully position them at 90 degrees to the gear center, you get a 90 degree phase shift and can treat them as an A B phased encoder.
I haven't done the math on this but it seems plausible.

Steve