Interested in an FRC-compatible remote control?

Happy champs week everyone!

Chap Research is now collecting down payments for FRC ChapRs, the FRC-compatible version of our ChapR remote control! Just as a bit of background, the pocket-sized device connects via Bluetooth to your roboRIO (using a Bluetooth dongle), then takes the place of the laptop by translating joystick data and sending it to your tele-op program. We’ve gotten a lot of interest in the ChapR, but we need commitments that are a little more firm in order to determine how many ChapRs to produce (and if we can produce ChapRs at all).

Note that we are a non-profit student organization associated with FRC 2468, so any “profits” go towards giving out free or reduced price ChapRs to teams in need (the same way we did with the FTC compatible version of the ChapR).

If you are able to commit and/or pay a small down payment, the ChapR will be $155 or $175 instead of the usual $200 (but only for a limited time!). Please visit our website for more information, and/or fill out this form if you are interested.

Looks interesting, and a nice alternative to buying a laptop just to run an old/demo bot.

A few questions:

  • What is the effective range? Last I checked Bluetooth was fairly short range compared to WiFi (<20-30ft), why did you decide to go this route instead of a 2.5/5GHz type transmitter?
  • Is it plug-and-play or does it require anything special in the robot code to work (if so, what languages is it compatible with)?
  • In theory, could one plug in a USB hub to get additional ports for more controllers, or is it hard limited to 2 USB devices?
  • Is this compatible with older cRio controllers or just the new RoboRios, and if so, how would one adapt a Bluetooth dongle to an older controller?


There’s bluetooth setups that will do over a mile (line of sight). Specifically look into the Sena line of motorcycle intercoms.

The ChapR has a range of about 75 feet (determined experimentally). We went with the RN42 (an off-the-shelf Bluetooth module) mostly because it was easy to use. Also, the ChapR was originally for FTC, so we went with Bluetooth to be compatible with the NXT.

RoboRIO Code:
The set-up on the roboRIO side is a quick deploy of our custom Linux daemon. The program just runs in the background and translates packets before sending them to itself (via Serial loopback). This means that any kind of robot code can work with it.

Additional Controllers:
The USB module we use (the VDIP2 module) doesn’t support USB hubs (or at least not that we’ve seen). Also, joysticks take a lot of power for our little 9V battery, so more than 2 might cause battery life issues anyway. You all are definitely welcome to experiment with it (as the code is completely open source).

cRIO Compatibility
The current ChapR is not compatible with the cRIO (given that it relies on the USB port and Linux environment of the roboRIO). However, we got about 75% into development of a cRIO version before we got the memo about the roboRIO, so if anyone really wants a cRIO version, we can release our LabView VI and a link to the RS232 Bluetooth to Serial plug-in. We’d definitely be up for answering questions if anyone wanted to finish a cRIO version from there.

…did that answer your questions? I may have missed something. I can also post links directly to documentation of the various modules if anyone wants.