Thread: How to measure low velocity
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Unread 06-04-2005, 10:16
nobtiba nobtiba is offline
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Re: How to measure low velocity
I'm using ADC 10bit of ATMEGA8535. The resolution is 1lsb = 1/1023 corresponding to (1/1023)*5 V = 0.0049V. ADXRS150's sensitivity is 12.5 mV/deg/s so 0.0049V means 0.0049/0.0125=0.392 deg/s =141.12 deg/hour.
That's means if gyro can measure all angular rate from -150 deg/s to +150 deg/s , my ADC can detect the rate at 141.12 deg/hour.
But when I rotate the table faster than that (It takes only about 5 minutes/cycle) the value I get is constant: 480. That is the value at zero point. It shows that ADXRS150 can't detect this slow rate. How to do with this prob?