Thread: How to measure low velocity
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Unread 06-04-2005, 08:17
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Re: How to measure low velocity
If I remember correctly (someone feel free to correct me if I'm wrong), even though it's actual resolution is that small... the values you get on the IFI controller will not be that accurate.

The Analog Inputs work from 0 to 1023. This covers a 5 volt range. Therefore, 1024 possible values / 5 volts = ~205 values per volt. I believe with the actual ADXRS150, it only works with + 1.5 volts around the 2.5 volt center. So a positive 1.5 volt means 150 degree/second rate.

So, that your 205 values per volt * 1.5 volts(at 150 degrees) ~= 308 values over the center (511) of the range. Now, (150 degrees / 308 values) = ~0.49 degrees/sec rate. So, by using the IFI controller, your accuracy is 0.49 degrees/sec. You won't see any change until you get it going at that rate.

I hope this makes sense, and I haven't gotten much sleep... so if I just completly messed up those calculations or put bad values or something, someone please correct me.
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