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Unread 21-04-2009, 00:05
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RobotPy Guy
AKA: Dustin Spicuzza
FRC #1418 (), FRC #1973, FRC #4796, FRC #6367 ()
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Re: "Java, Sun SPOT and the FIRST Robotics Competition"

Quote:
Originally Posted by AustinSchuh View Post
Correct me if I'm wrong, but I believe that updating the speeds of the motors on the robot 50 times a second while processing images using the rest of the CPU time would qualify. When I've tried to get code I've written under Linux to execute a loop 50 times a second without the timing being off by a fairly large percentage while using all of the available CPU resources, I've had trouble and found the best way to get the loop to execute every 20 ms is to use less CPU resources. Maybe I was doing it wrong, but that's been my experience.
You're right, obviously linux and vxWorks have different design goals. Probably would be a bit better if you were running in the kernel like we do on the cRio or if it were a realtime patched kernel, but hard to say -- I've no experience with realtime Linux.

In any case, I value the flexibility quite a bit more than I value the realtimeness. Cmon, a robot controlled by a shell script... would be pretty amusing.
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Maintainer of RobotPy - Python for FRC
Creator of pyfrc (Robot Simulator + utilities for Python) and pynetworktables/pynetworktables2js (NetworkTables for Python & Javascript)

2017 Season: Teams #1973, #4796, #6369
Team #1418 (remote mentor): Newton Quarterfinalists, 2016 Chesapeake District Champion, 2x Innovation in Control award, 2x district event winner
Team #1418: 2015 DC Regional Innovation In Control Award, #2 seed; 2014 VA Industrial Design Award; 2014 Finalists in DC & VA
Team #2423: 2012 & 2013 Boston Regional Innovation in Control Award


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