User's Manual

Document MV0319P.N

MVN User Manual

140

23 Synchronization with Third Party Devices

23.1 The Hardware

MVN BIOMECH Awinda uses the Awinda Station for synchronization.

From MVN Studio 4.1 and onwards, a Sync Station is provided with MVN BIOMECH for synchronization

purposes. Details on initializing the synchronization of MVN are provided in Section 7.2.14. The purpose

of this section is to provide some in-depth information about the synchronization possibilities.

The Awinda Station was originally created as a wireless master to control the Xsens MTw kit. The

Awinda Station and Sync Station were created specifically for the biomechanics market, where

synchronization with third party devices is an essential aspect of biomechanics research. For this reason

these Stations are equipped with 4 BNC connectors, two for receiving TTL pulses (Sync IN) and two for

sending TTL pulses (Sync OUT).

The hardware clock of the Awinda Station is very accurate. As an indication of the clock accuracy, the

error in the Awinda Station’s clock has a maximum of 1 µs every second (1 ppm). Therefore, in general,

the recommended scenario is that users relying on very tightly coupled synchronization use MVN

BIOMECH Awinda, and use it with the Sync Out settings.

With MVN BIOMECH Link, there is additional hardware making synchronization possible, this is software

synchronization. It is essential that the user understands that software controlled synchronization can

lead to undefinable latencies between button click in the software and reception of this signal.

Note that to synchronize with third party devices, BNC connectors are required at the Awinda Station or

Sync Station side. Since there are a multitude of system-specific connectors for third party systems,

Xsens does not provide the cables or connectors. Please contact the respective third party providers or

user manuals for details their hardware requirements.

23.1.1 Important note when receiving 5V synchronization pulses

On the back of the Awinda and Sync Stations are four BNC ports, two Sync In ports and two Sync Out.

The ports have been configured to send (Sync Out) or receive (Sync In) TTL pulses 0-3.3V.

This 3.3V is s lower than the voltage sent by some devices, which will be synchronized with the MVN

System. These other devices are based on 5V TTL levels. For this reason it is advised to separately

purchase (from eg Farnell) a 3.3 - 5V / 5V - 3.3V SMD level translator. This will prevent damage to the

SyncIn ports of the Awinda or Sync Station when receiving 5V pulses from third party systems. In general

sending a 3.3V pulse from an Awinda or Sync Station SyncOut port is fine. Therefore unless a threshold

of 5V of the third party system is required, in which case the 3.3V-5V SMD level translator will be

required.