---
title: "Calibrate IMUs"
canonical: "https://help.vicon.com/space/IMU/73108521/Calibrate%20IMUs"
format: markdown
---
In Capture and Visualize modes, if you plan to collect global angles, you must calibrate each of the IMU sensors to ensure that the data is stable and to minimize drift.

> ⚠️ **Important**  
> ⚠️ With Firmware 10 and later, sensor calibration is retained between trials when you collect global angles.  
> ⚠️ <span style="color: #1d1c1d">Calibration is continuous when global angles are either being streamed or captured onboard the sensor.</span>  
> ⚠️ <span style="color: #1d1c1d">The calibration is retained, even if you close the app, relaunch Capture.U and capture another trial with global angles, provided the new trial takes place within a two-hour period.</span>  
> ⚠️ However, you must re-calibrate for the next global angles trial if:
> ⚠️ 
> ⚠️ - The subsequent trial does not collect global angles, for example, if you collect global angles and then collect a raw data trial.
> ⚠️ - The sensors are inactive for longer than two hours.

**To calibrate the sensors:**

1. Start streaming global angles. (If you're not sure how to do this, see [Start Capture.U and choose a collection mode](https://vicon-help.atlassian.net/wiki/spaces/IMU/pages/73110578) and select the instructions for your chosen collection mode.)
  :check_mark: **Tip**: <span style="color: #1d1c1d">If you want to use real-time feedback to verify the calibration, you can calibrate in Real-Time Insight mode and then after calibration, capture global angles in To Sensor mode.</span>
  In all modes, when you start collecting data, a warning message is displayed if a sensor calibration is required.  
When you're capturing or streaming global angles in To Sensor or To Device modes, IMU sensors that require calibration display a 'Require Calibration' icon > Macro (inline-media-image)

 at the top right of the sensor on the sensor selection screen. (In Real-Time Insight and AR Visualization modes, the sensor calibration indicator is only displayed when you select the sensors.)
2. Wave the sensor in a figure-of-eight for at least 10 seconds, ensuring that it rotates through all three axes during the motion.
  > Macro (inline-media-image)

> Macro (inline-media-image)
3. Put the sensor on a flat surface and spin it through two full rotations around the **z** axis.
  :check_mark: **Tip:** To avoid any unwanted influence on the sensor, avoid placing it in proximity to anything metallic.
4. Wait at least five seconds until the data has stabilized.   
In Real-Time Insight and AR Visualization modes, you can observe that **x** angle is 0 and the **y** angle is 0 (the figure-of-eight provides enough information for the sensor to self-calibrate). However, the **z** angle may have a non-zero value, depending on how it is rotated relative to the magnetic north.
5. Rotate the sensor on the flat surface <span style="color: #1d1c1d">for at least five seconds</span><span style="color: #1d1c1d"> </span>until **z** is also 0.  
In To Device and To Sensor modes, to let you know that a sensor is calibrated, after 60 seconds, a **C** (Calibrated) icon > Macro (inline-media-image)

 is displayed at the top right of the sensor.  
In Real-Time Insight and AR Visualization modes, check that the graphs for all three axes are now at zero.
6. After you have calibrated each sensor, you can [attach the sensors to your subject](https://vicon-help.atlassian.net/wiki/spaces/IMU/pages/73120776) and collect data in the required [collection mode](https://vicon-help.atlassian.net/wiki/spaces/IMU/pages/73110578/Start+Capture.U+and+choose+a+collection+mode#StartCapture.Uandchooseacollectionmode-CaptureModes).

> ✅ **Tips for calibration:**
> ✅ 
> ✅ - As calibration is a continuous process, we recommend that after calibration you collect a trial in which the subject is wearing the sensors and in the same environment that they will be performing the movement to be collected.
> ✅ - If you plan to collect global angles, after the sensors are attached to a subject, allow a few seconds for onboard calibration to initiate before starting the movement that is to be collected.