Project

# Title Team Members TA Documents Sponsor
11 Noninvasive PoC Anemia Detection Device
Jeremy Dejournett
Mythri Anumula
Yamuna Phal design_review
final_paper
other
other
other
other
video
video
video
Purpose
Anemia is a condition that affects nearly 2 billion people, according to the WHO.Anemia is an entirely preventable disease, and once detected, the patient can take corrective action to restore their iron levels to a healthy state. According to Miller et al, the probability that you are affected by anemia increases five-fold in underdeveloped geographies [1]. Current non-invasive POC detection methods can be relatively expensive, and are difficult to move from place to place which makes them all the more inaccessible to the geographies that need it most. We propose to build a more portable and cost effective non-invasive anemia detection method by combining image and spectroscopy based detection methods in a wearable device that can be taken to regions without adequate medical facilities and used to help diagnose this preventable disease.

Design Requirements
The device we build will be required to provide accurate binary diagnosis of anemia based on both the oxygen level from a fingertip pulse oximeter[2], and the hemoglobin level based on RGB heuristics given by the pallor of the conjunctiva [3]. Data collection hardware will include a low-resolution camera for detecting conjunctiva pallor and wide-band photodiodes for pulse oximetry measurements. The two detection methods will be encapsulated in a single, wearable, fingertip device that delivers at least 9 correct diagnoses out of 10. This will be accompanied by a wristband that carries the power, processing, and diagnosis indication subsystems. The device will deliver all 10 diagnoses on a single charge, and be able to deliver diagnoses even while charging.

The minimum viable product will deliver two complete detection systems for data capture, a processing system for data analysis and detection, a power system for delivering the required capacity and charging needs, and a diagnosis indicator to relay the results to the testing administrator.

The total cost of the assembled product should be less than $50.

Detection System Design
Pulse oximetry is done to non-invasively estimate the concentration of both Hb and HbO2 by measuring the absorption coefficients at two separate wavelengths [2]. We intend to use at least wideband photodiodes, each with a filter for either red (660nm) or near-infrared (940nm), that are activated by two distinct light sources at red and near-infrared, which illuminate the tip of the finger in a 50% duty cycle. The light that perfuses the tissue is then detected by an array of wide-band photodiodes that detect the light which is transmitted through the tissue. This waveform is then offloaded to the processing subsystem, which uses the information of which light source is currently active alongside the incoming waveform to compute the ratio of AC to DC components in the detected waveform. This ratio is taken at both wavelengths, and the ratio of these ratios is used alongside a lookup table to compute an estimate of the percent saturation of O2 in the blood.
The second method of detecting anemia is to look at conjunctival pallor. The conjunctiva is the mucous membrane that covers the front of your eye and lines the under-eyelid. For many patients with anemia, the conjunctiva is distinctly pale and lacks redness [3]. A healthy patient has a distinctly red conjunctiva [5]. A diagnosis for anemia can be made accurately when conjunctival pallor is examined and then combined with other methods of detecting Hb levels, such as the pulse oximetry method described above.

References
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3685880/
[2] https://www.nxp.com/docs/en/application-note/AN4327.pdf
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1497067/
[4] http://ieeexplore.ieee.org/document/8249080/
[5] http://epomedicine.com/clinical-medicine/clinical-examination-pallor/

Prosthetic Control Board

Caleb Albers, Daniel Lee

Prosthetic Control Board

Featured Project

Psyonic is a local start-up that has been working on a prosthetic arm with an impressive set of features as well as being affordable. The current iteration of the main hand board is functional, but has limitations in computational power as well as scalability. In lieu of this, Psyonic wishes to switch to a production-ready chip that is an improvement on the current micro controller by utilizing a more modern architecture. During this change a few new features would be added that would improve safety, allow for easier debugging, and fix some issues present in the current implementation. The board is also slated to communicate with several other boards found in the hand. Additionally we are looking at the possibility of improving the longevity of the product with methods such as conformal coating and potting.

Core Functionality:

Replace microcontroller, change connectors, and code software to send control signals to the motor drivers

Tier 1 functions:

Add additional communication interfaces (I2C), and add temperature sensor.

Tier 2 functions:

Setup framework for communication between other boards, and improve board longevity.

Overview of proposed changes by affected area:

Microcontroller/Architecture Change:

Teensy -> Production-ready chip (most likely ARM based, i.e. STM32 family of processors)

Board:

support new microcontroller, adding additional communication interfaces (I2C), change to more robust connector. (will need to design pcb for both main control as well as finger sensors)

Sensor:

Addition of a temperature sensor to provide temperature feedback to the microcontroller.

Software:

change from Arduino IDE to new toolchain. (ARM has various base libraries such as mbed and can be configured for use with eclipse to act as IDE) Lay out framework to allow communication from other boards found in other parts of the arm.