ANNOUNCING: navX MXP Robotics Navigation Sensor

[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.

[JB987]

Our alpha and beta testing of the rRIO included vertical mounting and we had no problems with it's orientation.

[Ben Wolsieffer]

Originally Posted by JB987

Our alpha and beta testing of the rRIO included vertical mounting and we had no problems with it's orientation.

Are you talking about the navX, or simply the roboRIO by itself.

[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.

[slibert]

Originally Posted by lopsided98

It also looks like it can be connected over USB, which would make it even easier to mount it away from the roboRIO.

Connection over USB is definitely doable; but do note that the navX MXP RoboRIO I/O expansion capability is only accessible when navX MXP is connected via the MXP connector.

One interesting side note is that navX MXP can be connected *simultaneously* by both MXP connector AND USB. So you can access the navX MXP over the MXP Connector from your robot software and simultaneously monitor the navX MXP over the USB connector. There's a PC-based application called the navXMXPUI, more info on the Wiki (https://code.google.com/p/navx-mxp/wiki/navXMXPUI).

The navXMXPUI is really helpful to understand the full breadth of what the navX MXP can do, and should also help debug as you integrate the navX MXP into your robot.

[PeterBrock]

Originally Posted by slibert

Press Release - January 2, 2015
KauaiLabs, Inc. announces the navX MXP Robotics Navigation Sensor

The “9-axis heading” is enabled by magnetometer calibration tools (available online at no cost) and magnetometer disturbance detection and data fusion algorithms. This capability is known within the aerospace industry as an “Attitude/Heading Reference System” (AHRS). Kauailabs brings this high-tech AHRS capability to FIRST FRC teams - to use, learn and explore. navX MXP is a key component of Kauailabs’ ongoing efforts to make state-of-the-art navigation technologies used in autonomous vehicles (e.g., the Google Car) available to robotics students and enthusiasts as low-cost, open-source products.

The AHRS capability is very useful for field oriented driving.

Have you tried using the navX (or the nav6) for pose information? It would be useful to track robot position during the match.

[sanddrag]

Is it expected that more than 100 will be available? If you run out of stock, what's your lead time to get more up for sale?

[slibert]

Originally Posted by sanddrag

Is it expected that more than 100 will be available? If you run out of stock, what's your lead time to get more up for sale?

Lead time is 5 weeks. We will be deciding soon when to send out the next order, based on initial sales velocity.

[slibert]

Originally Posted by PeterBrock

The AHRS capability is very useful for field oriented driving.

Have you tried using the navX (or the nav6) for pose information? It would be useful to track robot position during the match.

If you mean using gravity-corrected linear acceleration to estimate current x,y position, the classic response is that double-integration of acceleration to derive first motion vectors and then a track from 0,0 would work for a short period of time but errors would grow quickly. We haven't tried this, but I think determining the error rate would be a very good idea.

I'm of the opinion that navX MXP plus scanning LIDAR is an elegant approach for localization. And low cost products like the LIDAR Lite are emerging that make it affordable for FRC teams to have long-range time-of-flight ranging. Based on that thinking, fusing a IR LED-based scanning LIDAR with navX MXP's heading and linear acceleration measures is the direction we're heading.

[slibert]

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. Does the navX have this approval?

Please see rule R58 of the 2015 FRC Game Manual, which indicates that the Kauai Labs navX MXP is approved as an "Active Device".

[Dunngeon]

Originally Posted by slibert

Lead time is 5 weeks. We will be deciding soon when to send out the next order, based on initial sales velocity.

Looks like you had that initial sales velocity. To those on CD, what is a good alternative to this IMU? If any.

[slibert]

Originally Posted by Dunngeon

Looks like you had that initial sales velocity. To those on CD, what is a good alternative to this IMU? If any.

Here's the link to the navX MXP on Andymark's website. They'll have 100 units in about a week. We are recommending people click on the "Email when available" link to be notified when they can be purchased.

http://www.andymark.com/product-p/am-3060.htm

[slibert]

Originally Posted by Dunngeon

Looks like you had that initial sales velocity. To those on CD, what is a good alternative to this IMU? If any.

As to alternatives, you might consider the nav6. It's software compatible with the NavX MXP. We have some remaining stock at http://www.kauailabs.com/store. The nav6 yaw accuracy is very similar to the NavX MXP, though the NavX MXP adds roborio expansion I/O, 9-axis headings and magnetic disturbance detection.

[Dunngeon]

Originally Posted by slibert

Here's the link to the navX MXP on Andymark's website. They'll have 100 units in about a week. We are recommending people click on the "Email when available" link to be notified when they can be purchased.

http://www.andymark.com/product-p/am-3060.htm

Oh, so they haven't sold yet. Thanks for the info!