User Guide
VMU931 User Guide
4.2 User integration
If you are not using our user interface, please note that the VMU931 will continuously stream data through
the USB cable as soon as the cable is plugged in. However, no data is saved within the sensor itself.
4.2.1 Connection
The VMU931 is seen as a serial device (COM port) when plugged into a computer. Since the sensor uses
a USB CDC to emulate serial communication through USB protocol, no settings need to be specified when
opening the serial port.
4.2.2 Commands
Every commands must be preceded by the prefix "var". For example, if you want the VMU931 to stream
accelerometers data, you need to send the characters "vara" ("var" being the prefix and ’a’ being the command).
Multiple types of data can be sent by the sensor:
• accelerometers, gyroscopes, magnetometers
• quaternions, Euler angles, heading
By default, the VMU931 sends the quaternions and the Euler angles as soon as the cable is plugged in. You
can toggle what the sensor streams by sending the following command:
Table 4.1: Toggle commands of the VMU931
Data Command
Accelerometers ’a’
Gyroscopes ’g’
Magnetometers ’c’
[Default] Quaternions
2
’q’
[Default] Euler angles
2
’e’
Heading
2
’h’
2
Limits the output rate to 200 Hz.
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