# Sensors

The *sensors* screen lists most of the sensors that are available to the FMU (internal or external). It allows you to start the calibration process for the listed sensors. The QGroundControl user guide has all information you need about calibrating the sensors. This step is very important for stable flights, it is required to do the calibration at least once and it should be redone whenever the drone starts flying less stable!

{% embed url="<https://docs.qgroundcontrol.com/en/SetupView/Sensors.html>" %}

![The sensor setup screen listing the sensors and their calibration status.](/files/-Lc6S_sMetHrrraGAemF)

You can check whether the sensors are properly calibrated using the *Analyze* widget, which can be found under *Widgets* at the top of the screen. This is a tool in QGroundControl that allows you to plot sensor values of sensors inside of the RDDRONE-FMUK66 in real-time.

![Select the analyze widget.](/files/-Lc6T0L9DuPmajhwb2Y0)

You can check the calibration of the sensors inside of the FMU by putting the drone on a flat, horizontal surface, and looking at the *ATTITUDE.roll* and *ATTITUDE.pitch* variables. If they are larger than 0.02 (both positive and negative), you should consider recalibrating the Accelerometer, Gyroscope and Level Horizon.&#x20;

{% hint style="info" %}
Note that the scaling of the graphs in the analyzer changes automatically! In some cases, very small changes might appear as if they are very large. Look at the current scale before drawing any conclusions!
{% endhint %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://nxp.gitbook.io/hovergames/userguide/qgroundcontrol/sensors.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.