ANNOUNCING: navX MXP Robotics Navigation Sensor

[slibert]

Originally Posted by schleprock

ok, if i hook it up to CS0 on the roborio, then i assume i need to use: kOnboardCS0

ie: SPI.Port.kOnboardCS0

not sure how to specify ports on the roborio. when most people talk about the various ports, they seem to mean those available through the mxp port. if they're talking about using a port that is detached from the mxp, but available on the mxp, i've seen brokenout used... so how do you specify the SPI port connections that are separate from the mxp port?

thanks

Yes, if connecting the RoboRio onboard SPI pins to the navX-MXP's SPI breakout connector pins, you would use SPI.Port.kOnboardCS0 in your software. This also means you would connect the corresponding pins on the RoboRIO's SPI connector block (eg, the CS0 pin, the MOSI, MISO, and GND pins) to their corresponding pins on the navX-MXP's SPI breakout connector.

[schleprock]

we successfully connected the SPI port using CS0 on the roborio to the SPI connection on the navx board. no connections via the mxp ports. we used the +5V pin on the roborio SPI port to power the navx. everything seems to work according to the DataMonitor java test.
one thing to note, in a previous post you had indicated that we needed to connect MOSI to MISO, that is NOT the case. when i tried that, no data. connecting MOSI to MOSI and MISO to MISO worked.
i know you had indicated using the USB for power, but both of our USB ports on the roborio are being used. it seems to do fine with the +5 pin from the SPI port. when does a roborio stage 2 brownout occur?

thanks for your help.

[slibert]

Originally Posted by schleprock

we successfully connected the SPI port using CS0 on the roborio to the SPI connection on the navx board. no connections via the mxp ports. we used the +5V pin on the roborio SPI port to power the navx. everything seems to work according to the DataMonitor java test.
one thing to note, in a previous post you had indicated that we needed to connect MOSI to MISO, that is NOT the case. when i tried that, no data. connecting MOSI to MOSI and MISO to MISO worked.
i know you had indicated using the USB for power, but both of our USB ports on the roborio are being used. it seems to do fine with the +5 pin from the SPI port. when does a roborio stage 2 brownout occur?

thanks for your help.

Please see item #2 on the navX-MXP Best Practices page for details on RoboRIO stage 2 brownouts. There's a link on this page to more details on stage 2 brownouts.

One other option is to provide 5V to the navX-MXP (via the 5V pin on the navX-MXP SPI breakout connector) from the VRM, which provides a regulated source of 5V that is not impacted by a RoboRIO stage 2 brownout.

[TannerM]

Hi,

When I try to compile my navX code on Eclipse using C++ it says "fatal error: AHRS.h: No such file or directory"

What can I do to fix it?

Inconceivable Programmers

[slibert]

Originally Posted by TannerM

Hi,

When I try to compile my navX code on Eclipse using C++ it says "fatal error: AHRS.h: No such file or directory"

What can I do to fix it?

Inconceivable Programmers

Sounds like your include paths are not set in your eclipse project.

Please see the navX-MXP RoboRio Library for C++ page and follow the instructions there. Your issue is likely addressed by following the directions in the "Configuring Eclipse Library and Include Paths" section, but there's other potentially useful information there, too.

[cjl2625]

Using the NavX with LabVIEW, attempting to open the device results in the code crashing and these error messages to appear:

I downloaded the v2 library, and simply dropped the "Z900_navX_Open.vi" block into begin.vi.
I tried under serial/i2c/spi but the result is always the same error.

Upon removing the NavX block, the errors go away.

[Caboose]

Originally Posted by cjl2625

Using the NavX with LabVIEW, attempting to open the device results in the code crashing and these error messages to appear:

I downloaded the v2 library, and simply dropped the "Z900_navX_Open.vi" block into begin.vi.
I tried under serial/i2c/spi but the result is always the same error.

Upon removing the NavX block, the errors go away.

Are you on the latest library? v2.0.5.0

[jojoguy10]

Hey NavX people,

Would it be possible to make a block that can reset the gyro to whatever you want (instead of zero)? I was going to go into your block and make the edit, but I found that it's a built-in function in the firmware on the board itself.

[slibert]

Originally Posted by jojoguy10

Hey NavX people,

Would it be possible to make a block that can reset the gyro to whatever you want (instead of zero)? I was going to go into your block and make the edit, but I found that it's a built-in function in the firmware on the board itself.

As you discovered, the "zero yaw" functionality is now performed by the navX-MXP onboard firmware. There were a few reasons for this, including that other values (specifically, the quaternions which represent numerically all of the cumulative rotations from the 0,0,0 origin point) also need to be updated as well to keep them in synch w/the navX-MXP yaw angle.

However, here's a link to some Java code that implements an "offset tracker" which can be used to subtract a given offset from any of the navX-MXP angles, including the yaw. Specifically, look at the applyOffset() method. You may find this helpful as you work on your own offset adjustment. What you want to do should be pretty straightforward - basically, you are subtracting a known value from the angle provided by navX-MXP. The only part that's a little complicated is handling the wraparound (at -180/+180 degrees).

[cjl2625]

I've been having some serious trouble with reliability of the NavX.

I run it for a few minutes, and then the NavX dies and the yaw reading stops updating. Occasionally, it starts working again after some seconds, but other times it requires a reboot to work.

Here's what I checked.
- I'm using the latest version of the library.
- NavX has been fastened down to the RoboRIO and ensured a secure MXP connection
- NavX is plugged in to USB at the same time as a backup power source, perhaps
- Tried using two different NavX units
- Tried using two different RoboRIOs on two different robots
- Tried using every data source (MXP Serial, MXP SPI, MXP I2C, USB Serial)
- Code usage is simple -- opening in Begin.vi, reading in Teleop.vi with Get YPRH block

Nevertheless, the result is always the same. Our ability to aim falls apart without a gyro, so this problem has been quite bothersome.

[slibert]

Originally Posted by cjl2625

I've been having some serious trouble with reliability of the NavX.

I run it for a few minutes, and then the NavX dies and the yaw reading stops updating. Occasionally, it starts working again after some seconds, but other times it requires a reboot to work.

Here's what I checked.
- I'm using the latest version of the library.
- NavX has been fastened down to the RoboRIO and ensured a secure MXP connection
- NavX is plugged in to USB at the same time as a backup power source, perhaps
- Tried using two different NavX units
- Tried using two different RoboRIOs on two different robots
- Tried using every data source (MXP Serial, MXP SPI, MXP I2C, USB Serial)
- Code usage is simple -- opening in Begin.vi, reading in Teleop.vi with Get YPRH block

Nevertheless, the result is always the same. Our ability to aim falls apart without a gyro, so this problem has been quite bothersome.

Can you please let me know which version of the firmware is currently loaded onto the navX-MXP units you have? The firmware for this year has resolved all known reliability issues. You should have at least v. 2.2 of the firmware loaded on the boards.

[cjl2625]

Originally Posted by slibert

Can you please let me know which version of the firmware is currently loaded onto the navX-MXP units you have? The firmware for this year has resolved all known reliability issues. You should have at least v. 2.2 of the firmware loaded on the boards.

Ah, that's probably it -- I just plugged the NavX in and ran the code; never thought about the firmware. I'll try updating it.

[Acocagne]

Does anyone have one of these to sell or have a supplier that has it in stock?
AndyMark and the manufacturer are both out of stock.

Thanks

[slibert]

Originally Posted by Acocagne

Does anyone have one of these to sell or have a supplier that has it in stock?
AndyMark and the manufacturer are both out of stock.

Thanks

More units should be available for sale at the KauaiLabs store by 3/22, and at AndyMark by approximately 4/3.

[DKolberg]

I am trying to verify operation using the navX mxp by hooking up to a PC with a USB cable. When I connect the usb from the pc to the navX nothing happens, the lights on the navX blink and go green, but he PC does not see any com port nor any device loading message. when I open the configuration utility no com ports show up. How do I configure the drivers so the PC can talk to the navX?