Add article on analyzing the logs

README.md

@@ -9,7 +9,7 @@
 * Simple and clean Arduino based source code.
 * Acro and Stabilized flight using remote control.
 * Precise simulation using Gazebo.
-* In-RAM logging.
+* [In-RAM logging](docs/log.md).
 * Command line interface through USB port.
 * Wi-Fi support.
 * MAVLink support.

docs/log.md

@@ -0,0 +1,72 @@
+# Log analysis
+
+Flix quadcopter uses RAM to store flight log data. The default log capacity is 10 seconds at 100 Hz. This configuration can be adjusted in the `log.ino` file.
+
+To perform log analysis, you need to download the log right after the flight without powering off the drone. Then you can use several tools to analyze the log data.
+
+## Log download
+
+To download the log, connect the ESP32 using USB right after the flight and run the following command:
+
+```bash
+make log
+```
+
+Logs are stored in `tools/log/*.csv` files.
+
+## Analysis
+
+### PlotJuggler
+
+The recommended tool for log analysis is PlotJuggler.
+
+<img src="img/plotjuggler.png" width="500">
+
+1. Install PlotJuggler using the [official instructions](https://github.com/facontidavide/PlotJuggler?tab=readme-ov-file#installation).
+
+2. Run PlotJuggler and drag'n'drop the downloaded log file there. Choose `t` column to be used as X axis.
+
+   You can open the most recent downloaded file using the command:
+
+   ```bash
+   make plot
+   ```
+
+   You can perform both log download and run PlotJuggler in one command:
+
+   ```bash
+   make log plot
+   ```
+
+### FlightPlot
+
+FlightPlot is a powerful tool for analyzing logs in [ULog format](https://docs.px4.io/main/en/dev_log/ulog_file_format.html). This format is used in PX4 and ArduPilot flight software.
+
+<img src="img/flightplot.png" width="500">
+
+1. [Install FlightPlot](https://github.com/PX4/FlightPlot).
+2. Flix repository contains a tool for converting CSV logs to ULog format. Build the tool using [the instructions](../tools/csv_to_ulog/README.md) and convert the log you want to analyze.
+3. Run FlightPlot and drag'n'drop the converted ULog-file there.
+
+### Foxglove Studio
+
+Foxglove is a tool for visualizing and analyzing robotics data with very rich functionality. It can import various formats, but mainly focuses on its own format, called [MCAP](https://mcap.dev).
+
+<img src="img/foxglove.png" width="500">
+
+1. Install Foxglove Studio from the [official website](https://foxglove.dev/download).
+
+2. Flix repository contains a tool for converting CSV logs to MCAP format. First, install its dependencies:
+
+   ```bash
+   cd tools
+   pip install -r requirements.txt
+   ```
+
+3. Convert the log you want to analyze:
+
+   ```bash
+   csv_to_mcap.py log_file.csv
+   ```
+
+4. Open the log in Foxglove Studio using *Open local file* command.