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Unread 04-03-2013, 21:22
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Optical Tachometer

After first trying to measure our tacos we figured out that we would probably get better success by measuring how fast one of our motors is going for our shooter.

However, because it is going 12k RPM the java code we use isn't able to measure the difference between it sensing on and off. Does anyone know of a way to measure time at smaller intervals in java than the regular timer class, which measures in milliseconds.
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Unread 04-03-2013, 22:17
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Re: Optical Tachometer

I don't think you'll be able to get the FPGA to read that extreme of input, will you?
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Unread 04-03-2013, 23:04
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Re: Optical Tachometer

Quote:
Originally Posted by THE DYNAMO View Post
After first trying to measure our tacos we figured out that we would probably get better success by measuring how fast one of our motors is going for our shooter.

However, because it is going 12k RPM the java code we use isn't able to measure the difference between it sensing on and off. Does anyone know of a way to measure time at smaller intervals in java than the regular timer class, which measures in milliseconds.
The FPGA has hardware counters that can read that fast. You can access them using the counter class.
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Unread 04-03-2013, 23:24
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Re: Optical Tachometer

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Originally Posted by Joe Ross View Post
The FPGA has hardware counters that can read that fast. You can access them using the counter class.
US1881 Hall Sensor and a diametrically polarized ring magnet rotating on-center should do the job with room to spare.
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