During a team meeting, I sat and looked at our miserably scraped 2012 robot. It had the cRIO and several electrical components removed for our current bot. As we all know, the cRIO setup is costly ($600), and I don’t think any team can produce that much money each year for a new robot.
As a result, I looked into a replacement controller. I realize this will not be FRC legal, but the end goal is to revive old bots for presentation (and a ~$50 budget). I’m not worried about pneumatic control at the moment since this particular bot doesn’t use them. All that’s really needed is 8 PWM outputs.
After some googling, I ended up with the BeagleBone Black. It has exactly 8 PWM outputs and seems very ideal for this project. Additionally, the API is BeagleScript, which runs on Node.js, and Node.js is my life.
Does anyone see any technical limitations with this before I drop $45? It doesn’t have to use any of the standard FIRST utilities (Drive Station), just remotely control 8 victors throw PWM. I’m am still open to suggestions for other boards.
The problem with the beaglebone is it does not have a Real time operating system. This means that there is a delay when inputting data and things don’t always work in real time. This becomes an issue for safety as proccesing can become delayed as you can not expect it to processe an input in a certain time frame.
If you’re looking for a cheap and simple set-up I would try the robot open http://www.team221.com/robotopen/
I’ve tested the code, and it works great with dual CIMs and an UNO R3, can’t see why it couldn’t be modified to run 8 motors. It also has code to check for errors in data packets, and to shut the system down if a data connection is lost.
If you need more processing power, just step up to a MEGA or DUE… just watch that the new Due processor has 3.3V I/O lines, as opposed to the 5V lines on the Uno and Mega.
One more thing. If you go this direction I would strongly recommend getting the 9xr or upgrading the 9x to er9x with a ISP programmer. It will give you way more programming options.
If your team has any spare VEX microcontrollers, they work great for controlling past FRC bots. They are a bit more expensive than the other options you are considering but they are reliable and easy to use. My team uses the older PIC microcontrollers for past FRC robots and other robots we’ve made for demonstrations.
I just started looking into all the different Turnigy options. These are especially attractive because they eliminate the need for a laptop and drivers station setup and appear to have some additional non-drive capabilities (like telling the shooter to run, controlling the compressor, etc). Can anyone with Turnigy experience comment on this and perhaps post an example of a recommended setup for an FRC robot? Our use, like many other teams, would be in keeping old robots “alive” with perhaps reduced functionality so that we can use the expensive cRIO hardware for more important projects.
The Turnigy receivers only output pwm signals so they will only control Talons and Jaguars (victor 884s and 883s are incompatible. We have not tested the 888s)
