New FMS Whitepaper

FIRST General Forum
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There is now a new FMS Whitepaper.

http://wpilib.screenstepslive.com/s/fms/m/whitepaper/l/608744-fms-whitepaper

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Wooooo!!!

FMS is a lot less of a black box now!

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slow hand clap Thanks marshall for you constant nagging about FMS. (yes, I saw the other thread where you talk to past marshall :rolleyes:)

I read the paper, FMS is very cool, love how it updates the VLANs in the switches and the WiFi SID’s to control who has access to the network during matches.

Would be interesting to hear more about the interfaces to the scoring counters. One of the big selling points for me for robotics is “not building robots that run around but building robots you can run around inside of” (ie factory automation) It sounds like they are using off the shelf process control devices.

A side interest is what all of this software is written in. I’d like to think some cool scripting language like Lua.

Now isn’t the time, but if Frank and the crew could do an episode of “How it’s Made, FIRST Power UP field edition” it would be great. Lots of cool stuff that they had to engineer, built, test and deliver.

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But… But… I’ve always known our team ended up on the 10/100 rather than the gigabit switch and that’s why we lagged out… :rolleyes:

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I’m very happy to see more details on FMS internals being published! Thanks to everyone at FRC Engineering who made this happen!

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I am making assumptions below.
After reading a document from 2007/2008 I believe that the PLC talks to the led displays through RS-485 (Modbus). As for counters/scoring, the plc counts input pulses or on/off signals from sensors in the field. Ex. for this year the the switches and scales send signal of whether they are off or on to the plc, the plc sends signals to the lights on the field to turn the on,off and which color/pattern. I’m thinking all this goes through an ArmorPOINT box, back to the plc through an ethernet cable. the plc could talk to the plc through protocols like ethernet, modbus, etc. using an OPC server to collect all data. the plc may check the condition of the field I/O every 10ms, yet the software may poll the plc for data every second, limiting the bandwidth and load on the fms software. The VLans, from images I’ve seen are done with a cisco router controlling what data goes between the vlans and by what device/IP

I too have been more interested in the arena control compared to the robot side.
One could easily create their own control system using hardware like a plc, remote i/o, sensors, e-stops. as for software some kind of HMI/SCADA software.

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Mostly correct on the LED displays; they are DMX512 specficially, which uses RS485 signalling.

I don’t think they’re using modbus though, as DMX has it’s own protocol.

That said, the connection is through the SCC’s managed switch. Old SCC’s (2015 and older IIRC) used the console serial port on the switch directly; newer SCC’s use an external RS485-to-ethernet adapter inside the SCC box (as the new switches don’t have a console port, or at least one that can be used in an appropriate manner).

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Scott, you should volunteer for field setup at an event, and specify you want to work on the field electronics setup. Would let you put the physical together with the logical that the whitepaper provides.

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