[magnets]

Originally Posted by yash101

Laaaaaaaggg!!! At competitions, if you are relying on vision processing heavily, you may get a 500 ms response time on your robot even if you had an i7 extreme, the most expensive one available. The network connection is unreliable. The ability to process within the robot and communicate via i2C or SPI or something hardwired to the cRIO. There's nothing more dependable than that. I think the 7 mbit/s internet connection speed cap is just random and in-required.

I think it would be most wise to process the images onboard, send the signals to the cRIO, and have a background process to update the driver station. Note, the driver station won't be very accurate at high speeds because of the laagg.

I agree that the speed cap is rather stupid, as the whole point of using 802.11 is to get higher connection speeds than that, but there really isn't lag if you're doing it right. Our camera stream managed 20 fps at only 3 mbit/s, and worked really well for processing. If you're seeing a 500 ms response time between your robot and your driver station, then something else is really wrong and you need to look at your software again. A robot isn't really driveable with that sort of lag.

In fact, I'd be willing to bet that our vision setup (processing on the ds laptop) has way less lag than your onboard processor. The ds laptop is an order of magnitude faster than an onboard processor, and the time from an image being sent from the robot to the laptop, the laptop processing it, and the laptop sending the coordinates of the target to the robot, was well under 100 ms all the time.

If you use a PID loop for alignment, you can compensate for any lag pretty easily while sacrificing response time.

When we used vision, we could align our robot with the target in under 1 second every single time. Also, watch videos from 341 in 2012. They were one of the fastest to get aligned, and they processed images on their driver station laptop. If you think that this process could be improved with lower lag, then prove it.

You can say (and be right) that a hardwired connection will be faster than the wi-fi connection, but unless you've actually done tests with well-written and complete setups in both arrangement, you can't comment on the effect of the increased time on the effectiveness of actual image processing. What you have above is just speculation with incorrect information.