vera-sleeve

The Venous Return Assist Leg Sleeve (VERA Sleeve) is a wearable device for management of symptoms of chronic venous insufficiency in the lower limb. This device is being developed as a project that started with the two-quarter-long course series BIOE 141A: Senior Capstone Biodesign at Stanford University in the 2015-2016 academic year and is continuing to preclinical patient studies.

Contents

This repository contains unit testing code for various subsystems of the test fixtures we used in developing the device. This repository also contains code to control the device and to monitor the test fixture we used to characterize the device. Here are the subdirectories:

• The doc/ subdirectory will contain project documentation.
• The ext/ subdirectory contains external code to support the device.
• The verasleeve/ subdirectory contains program modules.
  • The tests subdirectory contains test programs.
    • The arduino subdirectory contains firmware tests, i.e. tests to be uploaded to the Arduino board.
  • The VERASleeve subdirectory contains the Arduino sketch to drive the VERA sleeve independently of a computer.

Contributors

• Ethan Li: responsible for all device code.
• Alaina Shumate
• Preston Lim

Dependencies

Some unit tests are designed for execution with the Arduino IDE and its Serial Monitor and Serial Plotter utilities. All other code is written for Python 3.x, with the following libraries:

• Numpy for signal processing.
• Nanpy for serial communication with the Arduino.
• Pykka for concurrency based on the Actor model.
• PyQt4 for graphical interfaces.
• PyQtGraph for plotting in graphical interfaces.

Setup

Install the required libraries using your preferred method (such as pip and/or the package manager for your distribution). Then clone this repository, using the --recursive flag so that submodules are also cloned:

git clone --recursive git@github.com:lietk12/vera-sleeve.git

Then run the setup.py script and follow the instructions printed by that script to upload the Nanpy firmware to your Arduino.

Running

Tests

Tests in the verasleeve/tests/arduino subdirectory should be opened from the Arduino IDE and uploaded. Tests in the verasleeve/tests subdirectory must be run from the root directory of the package (i.e. the directory containing this README file), and can be run as follows:

python -m verasleeve.tests.name_of_test_to_run

For example, to run the blink test:

python -m verasleeve.tests.blink

Note that you may need to replace python with the executable name of python 3 on your distribution. On Arch Linux, this is just python, but on other distributions, this may be something like python3.

Leg Model Test Fixture Monitor

The panel to monitor sensor data from the leg model should be run from the root directory of the package, and can be run as follows:

python -m verasleeve.leg_monitor

This will open a window. You should press the connect button to connect to the Arduino on the test fixture. If the connection is successful, the program will immediately begin streaming sensor data onto the display plots and labels. You can pause (and reset) and resume data streaming with the corresponding toolbar buttons. You can also save a screenshot of the window with the corresponding toolbar button, though you may prefer to save an individual plot by right-clicking on it to access the PyQtGraph-provied contextual menu. Finally, you can toggle whether to show only the noise-filtered sensor signals or also to show the raw signal and the min/max signals (which correspond to the min and max values displayed in text labels).

Note that there appears to be some bug in PyQtGraph that will occasionally cause the plots to freeze and the program to segfault or hang. Just close the program and restart it.

Sleeve Control Panel

The panel to drive contractions of the VERA sleeve should be run from the root directory of the package, and can be run as follows:

python -m verasleeve.sleeve_panel

This will open a window. You should press the connect button to connect to the Arduino (which should be running the Nanpy firmware) on the VERA sleeve. If the connection is successful, the program will immediately begin driving contraction patterns on the VERA sleeve. You can adjust parameters, and you can also pause and unpause the contraction pattern. Note that, if you also want to run the leg model test fixture monitor, you may need to run that program and connect to the test fixture's Arduino before running the sleeve control panel program and connecting to the VERA sleeve's Arduino.

Sleeve Firmware

The Arduino sketch for autonomous use of the VERA sleeve (i.e. without being controlled by a computer) is in the VERASleeve folder. Upload it to run it. The current VERA sleeve prototype uses a Cheapduino, which should be uploaded as the "Arduino NG or older" ATmega8 model in the Arduino IDE. When you first supply power to the Cheapduino, it will pause for about 6 seconds for the bootloader to finish running; then the VERA sleeve firmware will take over and blink the LED while driving the motors on the digital pins.

Quality Assurance

Everything in this package was developed and tested on a laptop running Arch Linux. It should be possible to run this with (listed by increasing order of difficulty of installation) other Linux distributions, OS X, and Windows. However, you may need to deviate from some of the installation instructions to install all the dependencies.