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g.tec - g.USBamp LabVIEW High-Speed Online Processing

High-Speed Online Processing under LabVIEW

The High-Speed Online Processing under LabVIEW is now available for the g.MOBIlab+ and the g.USBamp. It supports Labview 8.6 and allows to easily create custom signal analysis experiments.

The High-Speed Online Processing under LabVIEW allows acquiring biosignals like EEG, EMG, EOG, and ECG with LabView 8.6. Therefore the High-Speed Online Processing under LabVIEW block is copied into a LabView project and can be connected to any other available LABVIEW block for further signal processing. The project is just started and the amplifier device driver guarantees that the Labview is updated in real-time.

This Rapid Prototyping environment speeds up the development cycle dramatically and within a few hours the first real-time experiments can already be made. The High-Speed Online Processing under LabVIEW allows using all LabView standards and writing your own LabView based programs.

The High-Speed Online Processing under LabVIEW gives access to the specific hardware settings like analog channel selection, digital I/O lines, SD card streaming,... Just put the High-Speed Online Processing under LabVIEW in your LABVIEW program and start the biosignal acquisition and analysis.

Biosignal data can be visualized and stored directly to the harddisk in LabView data format.

The figure below shows the model for the usage with g.USBamp.

Highlights

	acquire EEG, ECG, EMG, EOG data directly within LabView
	wireless biosignal data acquisition with g.MOBIlab+ or over USB with g.USBamp
	add graphically your own sophisticated data processing algorithms
	benefit from the Rapid Prototyping environment for developing, testing and releasing your biosignal applications
	no compilation of the Labview 8.6 is necessary for real-time analysis
	use standards of Labview 8.6’s for online analysis
	store data to a LabView file

Example High-Speed Online Processing under LabVIEW for the g.MOBIlab+:

g.MOBIlab+ transmits data via a bluetooth connection to your PC. In this case COM 14 is used for the transmission.

The example below displays the setup for reading eight analog input and eight digital input channels in a waveform graph. A LED array displays the status of the digital channels.

First select g.MOBIlab+ COM port where the device is connected to the PC or notebook and start the program.

Then select the channels to be acquired from g.MOBIlab+. The 8 digital channels can be used as input (channels 1 - 8) or output channels (channels 4 - 7) or can be disabled. Check the Testmode box to enable sending a sawtooth test signal from g.MOBIlab+.

The Waveform Graph shows the sawtooth signals with different frequencies on the different analog channels. The digital inputs blink from channel 1 to 8 in ascending order.

g.MOBIlab+ is also able to stream data onto a mini SD card. The SD card is inserted into the water protected battery compartment first.

Then start the Labview and with the channels to record check the Enable writing to SD card checkbox in the configuration dialog and enter as filename GMOBILAB.

g.MOBIlab+ is now streaming the data onto the SD card and is sending simultaneously the signals to the PC/notebook for visualization. After checking the signal quality of the biosignals press the Stop button. A dialog window appears which asks if you want to stop the data acquisition or if you want to disconnect the Bluetooth connection.

Click on Disconnect to keep on streaming the data onto the SD card but to close the signal transmission over Bluetooth. Now the subject can move freely around for 36 hours for home observation, sports activities or other physiological experiments.

When the subject returns from the experiment, startup the Labview again. The Bluetooth connection will be established again and the biosignal data can be visualized.

Finally stop the acquisition with the Stop button in the Labview. Now the SD card can be removed from g.MOBIlab+ and inserted into a card reader on the PC to analyze the physiological data. With a 1 GB SD card about 70 hours of data can be recorded.

Example High-Speed Online Processing under LabVIEW for the use with 4 g.USBamps: NEW!!!

g.USBamp Highspeed for LabVIEW (part of g.tec Highspeed for LabVIEW also containing g.BSamp and g.MOBIlab+) supports data acquisition from up to four g.USBamps.

One VI (gUSBamp.vi) is able to acquire data from the amplifiers and to set the corresponding digital outputs of each g.USBamp.

All four amplifiers must be connected to the computer, switched on and connected with the synchronization cables before the LabVIEW VI is started.

After device selection, the configuration dialog has one tab for each of the four amplifiers and can be configured separately. It is also possible to configure one amplifier and apply the settings to the other devices.

24 channels are displayed in the Data Out waveform chart, six channels for each amplifier as selected in the configuration dialog.

Second Life Control with aBrain Computer Interface by g.tec

Second Life is a virtual environment developed by Linden Lab. The program can be downloaded and accessed via the Internet. The users of Second Life, also called the residents can interact with each other through avatars. Residents can explore the environment, meet other residents or participate in group activities. It’s even possible to trade within Second Life!

Some people are meeting each other in their “Second-Life”.

Usually the users can control their avatars with the computer mouse and keyboard. Dr. Ushiba from Keio University, Department of Biosciences and Informatics interfaced Second-Life already to a BCI-system and used motor imagery as direct control for the avatar movement (YouTube link). g.tec implemented now a BCI control unit based on the P300 principle. This concept was already used for spelling and smart-home control. Therefore different symbols are arranged on a computer screen and are highlighted in a random order. If the subject focuses on one specific symbol that is flashing up the P300 response is induced and the BCI system is able to recognize this response and therefore the symbol. To control Second-Life different masks (GUI with icons) were created for moving around, chatting, ... specialized for the current task the user wants to execute.

Control mask of the P300 BCI with symbols to turn left, turn right, move forward, etc.

The EEG signal processing is realized in Simulink and is running in real-time to recognize the corresponding command. Then the command is transmitted to a Second-Life controller to translate it into Second-Life command.

Schematic of the Second Life control

The work was performed together with HTL Leonding (Schnürer Armin and Berth Alexander), who produces also a video showing the working setup .