ANNOUNCING: navX MXP Robotics Navigation Sensor

[mman1506]

Looks great! I really love the MXP breakout too, no screw terminals or PCB breadboards just an extension of what's on the RoboRIO itself.

[Amar Shah]

This looks really cool. I wonder if I can convince my team to buy one.

[Conor Ryan]

This is the coolest Control System Add On ever. You can do so much with it, all without the danger of overloading the main CPU.

Looking in the Wiki here are the list of examples:

• Field-oriented Drive

• Automatic Balancing

• Rotating to a given Angle

• Motion/No-Motion Detection

That is pretty impressive, I can't wait to see what some teams can do with this.


Any videos of it in action?

[slibert]

Originally Posted by Conor Ryan

This is the coolest Control System Add On ever. You can do so much with it, all without the danger of overloading the main CPU.

Looking in the Wiki here are the list of examples:

• Field-oriented Drive

• Automatic Balancing

• Rotating to a given Angle

• Motion/No-Motion Detection

That is pretty impressive, I can't wait to see what some teams can do with this.


Any videos of it in action?

Here's a video recently posted by the lead technical mentor of team 246, showing how they used the nav6 to implement field oriented drive. The navX is based on the same technology:

http://www.chiefdelphi.com/forums/sh...highlight=nav6

It's mentioned at about 5:30 and 10:30 into the video referenced in this post.

[Mr. Lim]

Just put in our order for one.

Team is excited to have a proper IMU on our robot this year!

Thanks, and good luck with the product!

[SpeedFreed]

I spent the large portion of my summer working with the Nav6 by Kauai Labs, and it was, by far, the easiest (and most accurate) gyro I had ever worked with. Ever. I never got around to using the other degrees (pitch, roll, linear acceleration), but it was worth it alone for just the yaw measurement, and it's easy integration into FOD. But that was just an offseason project, who knows what else tomorrow's challenge might allow us to do with it?

Needless to say, I already ordered one of the navXs, and you can be sure it will be on our robot next year.

[craigboez]

Because this is an "active" roboRIO expansion module, my understanding is that it needs explicit FRC approval before you can use it on your robot. Does the navX have this approval?

[Joe Ross]

Originally Posted by craigboez

Because this is an "active" roboRIO expansion module, my understanding is that it needs explicit FRC approval before you can use it on your robot.

It only needs approval if you plug in a motor controller or servo to it.

[craigboez]

Originally Posted by Joe Ross

It only needs approval if you plug in a motor controller or servo to it.

Thanks Joe. That would explain the lack of PWM outputs.

[slibert]

Originally Posted by craigboez

Thanks Joe. That would explain the lack of PWM outputs.

The navX does support PWM/Quad Encoders as well as standard GPIO. These pins are direct pass-throughs from the MXP Connector, so whatever RoboRIO drives out those pins is routed to the navx MXP Digital I/O connectors.

Any announcement regarding legality as an active device can only come from FIRST, who has indicated that all approved devices will be listed in this year's game manual, to be released tomorrow.

[craigboez]

Are there any restrictions or recommendations on how to mount the roboRIO? Is vertical ok?

[Greg Needel]

Originally Posted by craigboez

Are there any restrictions or recommendations on how to mount the roboRIO? Is vertical ok?

I can't speak for the orientation requirements of this board, but you could always use a cable to relocated it off of the roborio.

http://www.andymark.com/product-p/am-2997.htm

[slibert]

Originally Posted by craigboez

Are there any restrictions or recommendations on how to mount the roboRIO? Is vertical ok?

I'd definitely recommend horizontal alignment with the chassis.

We've put a decent bit of thought, though, into alternate mounting strategies.

Please take a look at the following wiki page and hopefully it provides enough detail regarding these alternate solutions:

https://code.google.com/p/navx-mxp/w...InstallOptions

You might want to consider the "One-wire connect via Floppy-disk Extension Cable" option and the "One-wire connect via USB Cable" options.

We were able to order some of the "Floppy-disk Extension Cables" on Ebay, and another poster just indicated that AndyMark is carrying them, as well.

[JesseK]

2 questions:
How much testing has this board undergone with the RoboRIO, outside of a Great like Joe Johnson?
The website shows 11 available. Is that true? Seems a bit low.

[slibert]

Originally Posted by JesseK

2 questions:
How much testing has this board undergone with the RoboRIO, outside of a Great like Joe Johnson?
The website shows 11 available. Is that true? Seems a bit low.

First, regarding the availability. As you noted, Kauai Labs has 11 remaining, but AndyMark will initially have 100 units for sale, I expect within a week or so.

As to the Roborio Testing: Like many others, Kauai Labs has been hampered because the RoboRIO firmware has not been made available to non-beta teams. So internally we do our firmware validation by running functional and stress-test code on Arduinos (connected to MXP connector) and PCs over USB. And electrical validation was performed on a new RoboRIO.

As to the Roborio-side libraries, one extremely helpful beta team tester got the nav6 working on the RoboRio in both LabView and Java, with small modifications to the libraries on the CRio. This proves out the WPI Library Serial Port support, as well as the Kauai Labs Serial Port-based nav6 libraries for Java and Labview. Since the navX MXP is backwards compatible w/the nav6, this means the navX MXP will work on the RoboRio.

As soon as the RoboRio firmware and WPI libraries are released (Jan. 3, 2015), Kauai Labs will be working overtime to first get the RoboRio libraries fully tested w/the navX MXP on LabView, Java and C++ platforms. Based on the work by the beta tester, and the maturity of the nav6 libraries, this should proceed quickly. Once that's solid, we'll next work to add extensions to the Serial Port-based Roborio-side libraries, which will make the new navX features (9-axis heading and Magnetic Disturbance Detection) accessible, too.

We're also finishing up documentation on the I2C/SPI protocols - should be posted on the wiki any day now - and after the Serial Port-based libraries are completed, we'll be creating some Roborio-side libraries for accessing navX MXP via these protocols too.

Given the constraints, that's the best strategy we could come up with - but we're open to input as to priorities as we make navx MXP available to FIRST teams.