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ahrs-visualizer reads orientation data on its standard input and uses that to display a 3D representation of the orientation. A Debian package is available for easy installation and the ahrs-visualizer source code is on github.

Currently, the presence of GPU-specific code means that it only works on the Raspberry Pi but it can probably be ported to other boards. It uses OpenGL ES 2.0.

Getting started for experts

If you are an embedded Linux expert, the only getting-started instructions you will need are:

• Get minimu9-ahrs working.
• Install the latest ahrs-visualizer Debian package or compile ahrs-visualizer from source.
• Run minimu9-ahrs | ahrs-visualizer.

Getting Started

Get minimu9-ahrs working

This program is meant to be used with minimu9-ahrs, a separate utility that reads data from the Pololu MinIMU-9 and computes its orientation. To get that working, please follow the instructions in the minimu9-ahrs tutorial.

Install ahrs-visualizer

If you are using Debian or some other distribution that allows you to install .deb package files, I recommend installing ahrs-visualizer using the Debian package. You can find the latest Debian package at http://www.davidegrayson.com/minimu9-ahrs/debian/ . Copy the URL of the latest .deb file, use the wget utility to fetch it from the web onto your Raspberry Pi, and then use dpkg -i to install it. For example, you could run the following commands to install a hypothetical version VERSION:

wget http://www.davidegrayson.com/minimu9-ahrs/debian/ahrs-visualizer_VERSION_armel.deb
dpkg -i ahrs-visualizer_VERSION_armel.deb

Alternatively, you can install the program from source. Please see README.textile in the source code repository for help.

Invoking

To pipe direction cosine matrix (DCM) data from minimu9-ahrs to ahrs-visualizer, simply run the following command:

minimu9-ahrs | ahrs-visualizer

The visualizer runs fine from the console; you do not need to run X.

Understanding the visualization

• The 3D model is a Pololu MinIMU-9 v2.
• The X axis is drawn as a red line.
• The Y axis is drawn as a green line.
• The Z axis is drawn as a blue line.
• The acceleration vector is drawn as a cyan line.
• The magnetic field vector is drawn as a yellow line.