6.111 Final Project, Fall 2015Michael Holachek and Nalini Singh

HeartAwarepulse oximetry system

HeartAware M. Holachek, N. Singh6.111 Fall 2015Motivation

● Develop variety of skills involved in FPGA design

● Explore medical applications

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

Figures courtesy Freescale “Pulse Oximeter Fundamentals and Design”

HeartAware M. Holachek, N. Singh6.111 Fall 2015Pulse Oximetry

Figures courtesy Freescale “Pulse Oximeter Fundamentals and Design”

HeartAware M. Holachek, N. Singh6.111 Fall 2015Pulse Oximetry

Figures courtesy Freescale “Pulse Oximeter Fundamentals and Design”

HeartAware M. Holachek, N. Singh6.111 Fall 2015Pulse Oximetry

HeartAware M. Holachek, N. Singh6.111 Fall 2015Pulse Oximetry

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

Pulse oximeter analog driving circuitry designed by Prof. Hom

pulse ox

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

Pulse oximeter analog driving circuitry designed by Prof. Hom

driving circuitry

pulse ox

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

Pulse oximeter analog driving circuitry designed by Prof. Hom

driving circuitry filtering op-amp

pulse ox

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

Pulse oximeter analog driving circuitry designed by Prof. Hom

driving circuitry filtering op-amp ADC

pulse ox

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

Pulse oximeter analog driving circuitry designed by Prof. Hom

driving circuitry filtering op-amp ADC

nexys 4pulse ox

HeartAware M. Holachek, N. Singh6.111 Fall 2015Analog Circuitry

custom HeartAware PCB

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015Signal Processing

mVNoisy Input Signal

Time(s)

HeartAware M. Holachek, N. Singh6.111 Fall 2015Signal Processing

mV

mV

Noisy Input Signal

Filtered Input Signal

Time(s)

HeartAware M. Holachek, N. Singh6.111 Fall 2015Signal Processing

Time(s)m

Vm

Vm

V2 /s

Noisy Input Signal

Filtered Input Signal

Squared Derivative

HeartAware M. Holachek, N. Singh6.111 Fall 2015Signal Processing

Time(s)

mV

mV

mV2 /s

mV2

Noisy Input Signal

Filtered Input Signal

Squared Derivative

Window Integration

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015Display Output

● Current heart rate

● Smoothed oxygen saturation waveform

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015System at a Glance

signal processing

pulse oximeter

analog control

display

audio

HeartAware M. Holachek, N. Singh6.111 Fall 2015Audio Output

beep440Hz frequency100ms duration

announcerannounces “40-199 beats per minute”

SD cardstorage of voice

samples

hr_pulse

hr_number audio mixervolume controls

HeartAware M. Holachek, N. Singh6.111 Fall 2015System Block Diagram

HeartAware M. Holachek, N. Singh6.111 Fall 2015Top Level Finite State Machine

HeartAware M. Holachek, N. Singh6.111 Fall 2015Potential Issues

● Signal variations

● RAM sizes / buffering

● Clear VGA graphics

HeartAware M. Holachek, N. Singh6.111 Fall 2015Timeline

Week 10/26

Week 11/2

Week 11/9

Week 11/16

Week 11/23

Week 11/30

Week 12/7

Project Proposal & Requirements Both

Analog Circuitry & PCB Michael

Signal Processing Nalini

Display Output Both

Audio Output Michael

Integration & Testing Both

Alternate Filters Nalini

UI Improvements, Night Mode Michael

Final Testing & Buffer Both