Project

# Title Team Members TA Documents Sponsor
32 Smart Pulse Oximeter
 Faris Zulhazmi
Jason Machaj
Sidney Gresham
 Shengyan Liu design_document1.pdf
final_paper1.pdf
other1.pdf
proposal1.pdf
# Smart Pulse Oximeter

Team Members:
- Jason Machaj (jmach5)
- Faris Zulhazmi (farisaz2)
- Sidney Gresham (sidneyg2)
# Problem

Describe the problem you want to solve and motivate the need.
The problem at hand is the inaccuracy of pulse oximeters in individuals with darker skin tones due to the way these devices interpret oxygen saturation levels. Pulse oximeters function by emitting light through the skin and measuring how much is absorbed to determine oxygen levels in the blood. However, higher concentrations of melanin absorb more light, leading to less accurate readings and potential overestimation of oxygen saturation in individuals with darker skin tones.
Addressing this problem is essential to improving equitable healthcare outcomes. A more inclusive and reliable pulse oximetry technology is needed—one that accounts for diverse skin tones and ensures accurate readings for all individuals.

# Solution

Describe your design at a high-level, how it solves the problem, and introduce the subsystems of your project.
This project aims to develop an adaptive pulse oximeter that adjusts the number of wavelengths used based on the user's skin tone. Traditional pulse oximeters often produce inaccurate readings for individuals with darker skin tones due to increased melanin absorption, which interferes with light-based oxygen saturation measurements. Many modern devices attempt to address this by using multiple wavelengths, but this approach increases power consumption.
Our solution integrates a camera and computer vision algorithms to determine skin tone and a wavelength-switching mechanism to optimize accuracy while conserving power. The device will also measure heart rate using the same optical components, making it a multifunctional health monitoring tool. All collected data will be displayed digitally for real-time user feedback.

# Solution Components

## Subsystem 1: Pulse Oximeter Subsystem

This subsystem will use infrared and red light to measure blood oxygen levels as well as heart rate. The way this works is that oxygenated blood will absorb more infrared light and pass through more red light. Deoxygenated blood does the opposite. Knowing this, we can capture and calculate the total blood oxygen level (SpO2) based on the ratio of red and infrared light passing through with a photodetector and a calibration algorithm. In order to properly measure the heart rate, the system will measure the photoplethysmography signal (PPG). When the photodetector records the light intensity, the blood volume increases as the heart beats, causing more light to be absorbed, reducing the signal. These wave-like pattern peaks correspond to the heartbeats and use the time difference between each successive peak to calculate the heart rate in BPM.

We will use the respective emitter LEDs and photodiodes:
- Red - Kingbright APT2012SECK
- Infrared - Vishay TSAL6100
- Photodetector - Hamamatsu S1223

## Subsystem 2: Color Recognition via Computer Vision Subsystem

This subsystem will utilize the “300K PIXEL USB 2.0 MINI WEBCAM” in conjunction with a flashing light to image the skin tone of the user. Using these images, color recognition will be employed to determine whether multiple wavelengths of light would need to be used to provide higher blood oxygen level measurement accuracy depending on user skin tone.

## Subsystem 3: Digital Display Subsystem

To display the contents of our measurements, data will be taken from the microcontroller and will be displayed on an external digital display. This will show the blood oxygen levels and heart rate to the user in real time.

## Subsystem 4: Power Supply Subsystem

This system must be able to operate on a rechargeable lithium-ion battery. This subsystem will provide appropriate power to each other subsystem/component using this battery with DC-DC converters (buck/boost converters). Reasonable operation time must also be available from one charge of the li-ion battery. Power efficiency can be managed via the switching of the oximeter from one to two wavelengths depending on skin tone, leading to longer operation time on one charge and higher efficiency.


# Criterion For Success

Describe high-level goals that your project needs to achieve to be effective. These goals need to be clearly testable and not subjective.

- Read blood oxygen within a 2% range.
- Read heart rate within a 2% range.
- Camera successfully captures and sends data to the microcontroller.
- Ability to change wavelengths depending on skin tone.
- Assistance via computer color recognition (to show success, try with and without to see difference in measurement)
- Correctly display measured blood oxygen levels and heart rate.

Covert Communication Device

Ahmad Abuisneineh, Srivardhan Sajja, Braeden Smith

Covert Communication Device

Featured Project

**Partners (seeking one additional partner)**: Braeden Smith (braeden2), Srivardhan Sajja (sajja3)

**Problem**: We imagine this product would have a primary use in military/law enforcement application -- especially in dangerous, high risk missions. During a house raid or other sensitive mission, maintaining a quiet profile and also having good situational awareness is essential. That mean's that normal two way radios can't work. And alternatives, like in-ear radios act as outside->in communication only and also reduce the ability to hear your surroundings.

**Solution**: We would provide a series of small pocketable devices with long battery that would use LoRa radios to provide a range of 1-5 miles. They would be rechargeable and have a single recessed soft-touch button that would allow someone to find it inside of pockets and tap it easily. The taps would be sent in real-time to all other devices, where they would be translated into silent but noticeable vibrations. (Every device can obviously TX/RX).

Essentially a team could use a set of predetermined signals or even morse code, to quickly and without loss of situational awareness communicate movements/instructions to others who are not within line-of-sight.

The following we would not consider part of the basic requirements for success, but additional goals if we are ahead of schedule:

We could also imagine a base-station which would allow someone using a computer to type simple text that would be sent out as morse code or other predetermined patterns. Additionally this base station would be able to record and monitor the traffic over the LoRa channels (including sender).

**Solutions Components**:

- **Charging and power systems**: the device would have a single USB-C/Microusb port that would connect to charging circuitry for the small Lithium-ion battery (150-500mAh). This USB port would also connect to the MCU. The subsystem would also be responsible to dropping the lion (3.7-4.2V to a stable 3.3V logic level). and providing power to the vibration motor.

- **RF Communications**: we would rely on externally produced RF transceivers that we would integrate into our PCB -- DLP-RFS1280, https://www.sparkfun.com/products/16871, https://www.adafruit.com/product/3073, .

-**Vibration**: We would have to research and source durable quiet, vibration motors that might even be adjustable in intensity

- **MCU**: We are likely to use the STM32 series of MCU's. We need it to communicate with the transceiver (probably SPI) and also control the vibration motor (by driving some transistor). The packets that we send would need to be encrypted (probably with AES). We would also need it to communicate to a host computer for programming via the same port.

- **Structural**: For this prototype, we'd imagine that a simple 3d printed case would be appropriate. We'd have to design something small and relatively ergonomic. We would have a single recessed location for the soft-touch button, that'd be easy to find by feel.

**Basic criterion for success:** We have at least two wireless devices that can reliably and quickly transfer button-presses to vibrations on the other device. It should operate at at *least* 1km LOS. It should be programmable + chargeable via USB. It should also be relatively compact in size and quiet to use.

**Additional Success Criterion:** we would have a separate, 3rd device that can stay permanently connected to a computer. It would provide some software that would be able to send and receive from the LoRa radio, especially ASCII -> morse code.