How to mount Razor IMU on Clearpath Husky Robot

Question

I hope you can help me with my Razor IMU configuration (SEN-10736). I've followed the razor_imu_9dof tutorial in order to make the board work under ROS Indigo and everything works great!

I'm just getting confused about the IMU orientation on my Clearpath Husky robot: should I mount the board by aligning the x-axis (the axis which points towards the short edge with the connector holes) towards the front bumper of my robot? Or should I use the frame orientation specified on the sensor board?

The side with the electronics component should point up or down?

By looking at the visual tool under ROS, I think I should place the IMU with the short edge pointing towards the front bumper, but what about the component side? Should it face up or down?

• The roll values should be positive when moving on the right side or on the left side?
• And the pitch values should be positive when moving up or down?

Thank you!

EDIT:

EDIT2:

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Originally posted by Marcus Barnet on ROS Answers with karma: 287 on 2017-03-07

Post score: 0

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Original comments

Comment by aarontan on 2018-08-08:
did you find razor imu to work better than the um7 that comes with the husky?

Comment by Marcus Barnet on 2018-08-08:
I have a very old husky version and it doesn't include any imu sensor so I can't help you, sorry

Comment by Marcus Barnet on 2018-08-08:
The razor surely worked fine

Answer 1

See the documentation for the razor imu, section "Coordinate Frames" (You have to select indigo first):

The definition of the coordinate frame used by the Razor_AHRS firmware differs from what is printed on the board and also from the ROS coordinate frame. You will be exposed to these differences when testing the Razor AHRS and ROS topic output in the testing section below.

The Razor_AHRS firmware uses:

X axis pointing forward (towards the short edge with the connector holes)

Y axis pointing to the right

Z axis pointing down

Ignore the labelling on the board and use this coordinate frame when mounting the Razor.

So to answer your question, you are correct:

• Ignore the axis labels
• Components up
• Roll positive clockwise
• Pitch positive on front down

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Originally posted by Humpelstilzchen with karma: 1504 on 2017-03-08

This answer was ACCEPTED on the original site

Post score: 1

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Original comments

Comment by Marcus Barnet on 2017-03-08:
Thank you for your answer! I edited my first post in order to add a picture. The Z-axis should point UP since the Z-axis of the robot points up, is it correct?

Comment by Humpelstilzchen on 2017-03-08:
This is correct.

Comment by Marcus Barnet on 2017-03-08:
Thank you for your support!