---
title: "Use Active Wand"
canonical: "https://help.vicon.com/space/ActiveWandDoc/339345815/Use%20Active%20Wand"
format: markdown
---
Use **Strobe** mode whenever possible as it produces good calibrations with a longer video camera shutter period, giving brighter video. **Continuous** mode may produce significant motion blur at a shutter period that works well in **Strobe** mode. In addition, if you're using SDI video with Genlock or VESA offset to align shutter timing with Vicon cameras, selecting **Strobe** mode makes it easier to see if the shutter timing is aligned.
However, in the following cases, **Continuous** mode may give better results:
- When you're initially setting up the volume
- In large volumes (over approximately 50 m), if the cameras' strobes are not bright enough to activate the wand’s sensor
- When working with Vicon Viper or ViperX cameras
- In cases of high light pollution, for example, in direct sunlight
- To calibrate camcorders
> ⚠️ **Important**
> ⚠️ Ensure your Vicon Active Wand is not exposed to unsuitable environmental conditions such as wet or dusty environments.
### > Macro (anchor)
When to use the Active Wand
To maintain the high quality of your Vicon motion capture system's tracking, you must calibrate the system periodically. The calibration process adjusts the parameters of the cameras (their positions, orientations, and lens parameters) based on camera observations of the markers on the wand.
In the following circumstances, the calibration may become less accurate and the captured data degraded:
- The cameras move or are bumped
- The temperature of the cameras changes significantly
- The environment changes significantly
For this reason you must calibrate the system regularly. For more information on when and how to calibrate your Vicon system, see your Vicon software documentation.
> ❌ **Warning**
> ❌ If your Active Wand is damaged, do not use it. For repair or replacement, please contact Vicon Support.
For details of the calibration process, see the following information:
> Macro (toc)
> ⚠️ **Note**
> ⚠️ Before you use Active Wand, make sure the Wand pattern control (see > Macro (inline-media-image)
> ⚠️
> ⚠️ in [Active Wand controls](https://vicon-help.atlassian.net/wiki/spaces/ActiveWandDoc/pages/339348612/Configure+Active+Wand#Controls)) is in its central (standard) position.
## > Macro (anchor)
Synchronize Active Wand to the cameras
When the wand is in Strobe mode, the camera strobe sensors (one on each side of the wand) receive the signal from the cameras' strobes and lock into it so that the wand can limit the light it emits outside of the camera shutter period.
Strobe mode works with any Vicon camera frame rate but it may have difficulty in locking into the camera strobes at high frame rates if the cameras' strobe intensity setting is low. If this is an issue, calibrate the cameras at a lower frame rate and then capture at the required higher rate.
To synchronize the Active Wand to the cameras:
1. Turn on the Active Wand.
2. If necessary, change the LED Mode switch to Strobe mode.
:info:** ****Notes**:
- When you use the Active Wand in Strobe mode, you may notice a faint buzzing noise. This is normal and does not affect the performance of the wand.
- When in Strobe mode, the Active Wand will not sync to camera rates less than 20 Hz.
3. Place the Active Wand in the capture volume where it is visible by the Vicon cameras.
When the wand enters Strobe mode, it can take some time to find the camera strobe signals, to ensure they are stable and consistent. During this phase, the status light remains orange and no light is output on the marker LEDs.
When the status LEDs turn blue and the marker LEDs output light, the Active Wand is synchronized to the cameras.
> ✅ **Tips**
> ✅
> ✅ - In environments with light or magnetic interference, turn on the wand in an area that is well lit by strobes and away from other sources of NIR/IR light or significant electromagnetic interference, and hold it at a comfortable height. If synchronization remains problematic, try Continuous mode.
> ✅ - If the wand picks up multiple Vicon strobes or similar sources of strobed light, it may be unable to lock to either one. To resolve this, block out the unwanted strobe(s), eg, by covering one camera strobe sensor with your thumb and aiming the opposite side of the wand towards a strobed camera in the Vicon system that you want to lock to.
After the wand has locked into the camera strobes, it is more resilient to interference as it has learned the strobe rate to work with. The wand can operate for some time without receiving a strobe pulse, staying locked and visible to the cameras. However, the higher the system frame rate is set, the shorter the time the wand can operate without receiving a strobe pulse. Other sources of strobed light may also shorten the time the wand can operate without a strobe pulse from the cameras.
When too long an interval has occurred between strobe pulses from the cameras, the wand loses its lock to the camera strobes and resets, indicated by the status light turning back to blue.
Strobe mode outputs more light in the camera shutter period, despite looking dimmer than Continuous to the naked eye. You can use Strobe mode with decreased brightness instead of Continuous mode with increased brightness: this substantially increases the time the batteries last between charges.
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## Calibrate the cameras
The system calibration process depends on the Vicon application software recognizing the dimensions and relative marker positions of a specified reference device (in this case, the Vicon Active Wand). This definition of a reference device is contained in a Vicon Labeling Skeleton (VSK) file. When you configure the calibration process in your Vicon application software, you load its VSK file.
> ⚠️ **Important**
> ⚠️ To calibrate your Vicon system, you must have a reference device definition file (VSK) that matches your reference device. By default, only Vicon Active Wand definitions are pre-installed in the software. (To use legacy or custom reference devices, you must import into your Vicon application software a definition file that fully describes your device.)
With the Active Wand synchronized to the cameras as described in [Synchronize Active Wand to the cameras](#SyncToCameras), you can now wave the wand in the volume as described in the following steps. This enables the Vicon application software to calculate the physical position and orientation of each Vicon camera in the capture volume based on the movement of the wand.
1. Ensure your Vicon application software is connected to your Vicon system and that the correct wand definition is selected in the software. For details, see the documentation for your Vicon software.
2. Wave the wand throughout the empty capture volume, ensuring that the LEDs on the wand are visible to the cameras, until sufficient wand frames are spread evenly across the field of view for each camera. For information on how to achieve the best possible wand wave, see [Best practices for a wand wave with Active Wand and Active Wand Hybrid](#WandWaveBestPractices).
The Vicon camera display and your Vicon application software provide feedback to help you determine when enough wand data has been acquired to calibrate each camera. For details, see the documentation for your Vicon software.
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### Best practices for a wand wave with Active Wand (IR only) and Active Wand Hybrid (NIR & IR)
The technique for an optimal wand wave for Vicon Active Wand (IR only) differs from that for achieving the best wand wave with previous versions of Active Wand:
- With previous versions of the Active Wand, the direction in which the upper face of the the wand was held in relation to the cameras was important.
- Due to the unique design of Active Wand (IR only), holding the upper face of the wand to the cameras is no longer relevant as both faces are equally important.
- Holding the wand sideways instead of flat (see [Best practices for a wand wave with Active Wand (IR only)](#WandWavev4BestPractices)) increases the visibility of the wand to the cameras.
- For the best wand wave, ensure that the wand is visible to as many cameras as possible at the same time. This enables the Vicon software to reconstruct markers at their particular 3D locations precisely and helps to ensure wand frames are collected as quickly as possible, which reduces the overall length of the wand wave.
The best technique for a wand wave with Active Wand Hybrid (NIR & IR) differs from that for previous versions of Active Wand and from Active Wand (IR only). For details, see [Best practices for a wand wave with Active Wand Hybrid (NIR & IR)](#BestPracticesAWv4Hybrid).
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#### Best practices for a wand wave with Active Wand (IR only)
To achieve the most effective wand wave with Active Wand (IR only), follow these principles:
- For best wand visibility, hold the wand oriented sideways (as shown in the following image), with the two wand faces pointing left-right rather than up-down (flat).
This is so the small dead zone (the LEDs cannot be detected reliably at near 90°) coincides with the operator’s body.
- Wave the wand up and down (in a similar movement to using an axe) or from side to side (from left to right and right to left), without turning it, and move around the volume to cover the space. Remember that the position of the wand in relation to the cameras is important. You can wave the wand from side to side or up and down, depending on your preference. If you want to reach high up in the volume, you may find an up-and-down motion more effective.
- Hold the wand as far away from your body as possible, to reduce occlusion caused by your body blocking the cameras from the wand. You may find that using the extension handle helps to achieve this, as well as enabling you to cover the whole volume more efficiently, with less walking.
- For good coverage, wave the wand high and low within the volume.
- You will always achieve better results by showing the wand to both sides of the volume at the same time, rather than separately to one side then the other.
- You don't need to include any kind of twisting motion.
> ❌ **Warning**
> ❌ When waving the wand in large volumes, where repeated movement may cause injury, be particularly careful to avoid any twisting motion, which is no longer required for a successful calibration.
> Macro (anchor)
#### Best practices for a wand wave with Active Wand Hybrid (NIR & IR)
The best technique for a wand wave with Active Wand Hybrid (NIR & IR) differs from that for previous versions of Active Wand and from Active Wand (IR only):
- Wave the wand using a movement similar to a figure-of-eight, although any technique in which the wand is twisted as it’s waved produces good results.
:info: Unlike the recommended movement for Active Wand (IR only), an axe motion or side-to-side movement is not recommended for Active Wand Hybrid (NIR & IR) as these techniques do not include twisting.
- If IR and NIR cameras are evenly spread around the volume, ensure the wand wave includes a twisting motion, to ensure that it is seen by all camera types in all directions.
- Be sure to include a twisting motion as you move around the volume to cover the space, bearing in mind that the position of the wand in relation to the cameras is important.
- For good coverage, wave the wand high and low within the volume.
- Note that the 'frying-pan' technique (where the wand is held flat and moved in a circular motion) used for previous versions of Active Wand is unlikely to be effective, as one of the sides faces downward, and does not contribute data.
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> Macro (anchor)
## Set the volume origin
In setting the volume origin, the Vicon application software measures the position of the Active Wand in the capture volume and sets the global coordinate system.
The objective of setting the volume origin is to set the global coordinate system so that subjects are displayed the right way up and so that you can change the way data is visualized in the Vicon application software workspace.
1. To identify the coordinates of the global origin (0,0,0), which represents the center of the capture volume, and the global axes (X,Y,Z), which represent the horizontal and vertical axes of the capture volume, place the Active Wand on a force plate (if used) or on the floor as described in the following steps.
- **If you are using force plates**:
- Choose one of the force plate corners to be the position of the origin of the global coordinate system.
This enables your force plates and the Vicon capture volume to share a common coordinate system.
- To position the wand correctly, screw each force plate alignment guide into the relevant set of holes and align the guides with the edge of a force plate.
The alignment guides ensure that you place the wand in the same position on top of one of the force plate corners each time you perform a calibration.
- Ensure that the bubbles in the spirit level are in the center, indicating that the XY plane of the wand is parallel to the force plate.
This adjustment doesn’t have to be precise as you will be able to set the floor plane in the software later.
⚠️ **Important**: Use the spirit level as a quick way to obtain a rough estimate of the floor plane. To obtain a more precise measurement later, you can enable your Vicon application software to detect markers scattered across the volume floor. For more information, see the documentation for your Vicon software on setting the floor plane.
- **If you are not using force plates**:
- Use the etched lines at the top of the wand (for location, see > Macro (inline-media-image)
in [Active Wand controls](https://vicon-help.atlassian.net/wiki/spaces/ActiveWandDoc/pages/339348612/Configure+Active+Wand#Controls)) as a guide to where the origin is to be located.
- Allow the wand to rest on its pivot (located near the center, on the underside) and adjust the feet of the wand (under each of the level wheels) by turning the level wheels to lower or raise the wand. Ensure that the feet are all as flat as possible.
This adjustment doesn’t have to be precise as you will be able to set the floor plane in the software later.
⚠️ **Important**: Use the spirit level as a quick way to obtain a rough estimate of the floor plane. To obtain a more precise measurement later, you can enable your Vicon application software to detect markers scattered across the volume floor. For more information, see the documentation for your Vicon software on setting the floor plane.
- Start with the handle and adjust the foot between the fixed foot and the hand grip, and then adjust the other foot until the bubbles in the spirit level are in the center.
- On the top edge of the wand, adjust the foot on the left end until the bubbles in the spirit level are in the center.
:info: **Note**: To prevent reflections interfering with leveling the wand, you can toggle on/off all the LEDs on the underside of the wand. To do this, press both brightness buttons (for location, see > Macro (inline-media-image)
in [Active Wand controls](https://vicon-help.atlassian.net/wiki/spaces/ActiveWandDoc/pages/339348612/Configure+Active+Wand#Controls)) at the same time.
2. Ensure the Active Wand is now either on top of a force plate (if used) or flat on the floor in the center of the capture volume in the field of view of at least 3 cameras.
3. Ensure the left corner of the wand is where you would like the volume origin to be and in the orientation that you would like the horizontal X and Y axes to be. The calibration process calculates the vertical Z axis from the positions of the X and Y axes, as shown in the following image.
For details on calibrating your Vicon cameras and the capture volume, including how to set the floor plane, see the documentation for your Vicon application software.