How to use the hardware

Four LEDs indicating different operation modes

An image explains the roles of three buttons on PCB

An image indicates where to put a microSD card

An image indicates the location of a power indicator LED

An image shows wehre to connect an external actuator and its drive unit

Insert a microSD card to OpenGUT hardware.
Turn on OpenGUT hardware by using the on-board toggle switch.
Toggle mode to logger mode by using the mode selection switch.
Press the run button to start recording.
Place module in wearing belt, with a stethoscope placed in between the stomach and the hardware.
When recording is complete, click the run switch to stop current recording.
Turn OpenGUT hardware off by using the on-board toggle switch.
Remove the microSD card from the hardware.

Load a microSD card on a computer.
Specify wave file(s) you want to play using the OpenGUT software (up to two files can be supported) and download the wave files to the microSD card.
Remove the microSD card from the computer and insert it to the OpenGUT hardware.
Turn OpenGUT hardware on by using the on-board toggle switch.
Click the mode selection button to select either file A or B to playback.
Place the hardware in a wearing belt, along with an actuator device optionally, and wear the belt.
Once ready, press the run button to begin playback.

This mode does not require a microSD card.
Turn OpenGUT hardware on by using the on-board toggle switch.
Once the hardware has been placed in the belt and worn, click the mode selection button (could be multiple times) to set it to Mode 2.
Click the run button to start the loopback session.
Click the run button again to stop the loopback session.
For real-time audio visualization and recording on the computer, connect the on-board sound output to a headphone amplifier or an audio amplifier (i.e. Scarlett Solo) to link the audio output to your computer. Sound processing software, such as Audacity or AudioMass, for visualization and recording.
For real-time haptic feedback to the stomach, source the on-board sound output to a suitable amplifier, such as Adafruit MAX9744 breakout board or similar, to connect the transducer. This allows for experimentation with different types of transducers for feedback.