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Unread 10-01-2012, 15:13
Greg McKaskle Greg McKaskle is offline
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Re: Camera-to-Driver Station latency

I don't have a recent measure, but I have measured it in the past by enabling an LED (assumed to be an instantaneous stimulus), and doing very cheap pixel intensity test on the controller, laptop, or wherever you would like to determine the latency.

The camera has its own internal clock and that will use that clock to start and stop exposures -- no more often than every 33ms. We have no good way to synchronize or control that clock, so the code will make numerous measurements possibly with intentional random jitter, and look at it statistically to find the distribution of times. This will give you a range of expected lag for a particular setup.

I'll see if I can redo the measurements to the cRIO and to the dashboard and post the distribution graphs.

The FPS numbers are far easier to measure and are independent of the lag.

Greg McKaskle
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