A Modular, Wireless EEG Platform Design
Tyler S. Witt · OhioLink ETD Center (Ohio Library and Information Network) · 2014
Electroencephalography (EEG) is the measurement of electrical activity that takes place in the brain.EEG and the study of the waveforms thereby acquired are useful in the clinical and medical range.In addition to this, commercial applications and electronics are ever approaching the use of such technology as well.Moving forward in time, these technologies (as all technologies in general) are moving more towards becoming solutions composed entirely of embedded technology.As the technologies get smaller and more complex, the capabilities of current medical solutions are continually improving.The work presented in this thesis shows how embedded technologies can interface to completely comprise an entire EEG system.Among all things, this design is modular and wireless.This novel design concept provides ways to take an existing solution and improve its portability and adaptability, without compromising the accuracy of the system as a whole.The design itself is based on three main components: an Analog Front End, a 16-bit Microcontroller, and a Bluetooth Transceiver.This work will show that by interfacing these three main embedded devices, the results of a proven clinical EEG system can be replicated.Additionally, this work will show that this design can exceed in value the existing system due to its vast superiority in portability and adaptability.iii I take great pride in and have a great appreciation for everyone who has helped me throughout the course of my Master's studies at the University of Cincinnati.I am first off very appreciative of my immediate family.My mother Judy, my father Dennis, and my brother Michael have always been supportive of my academic endeavors.Through the ups and downs, and all the delays, they were always there to push me as far as I could go.I would also like to thank Dr. Fred Beyette for being so patient and helpful throughout this entire process.Under Dr. Beyette's guidance, I have been able to expand my thoughts and interests in the embedded processing applications space, especially focusing on medical technologies.I would also like to thank any and every professor at the University of Cincinnati who imparted knowledge and wisdom to me in my years here.Specifically, I would like to extend a special thanks to Dr. Carla Purdy and Dr. Paul Talaga for serving on my defense committee and showing an interest in my work.I would also like to thank all of my close friends that I have known throughout my time at the University of Cincinnati.When I needed a break from anything (or everything), I could always count on at least one of my friends to be there to give balance to my life.The final group of people I would like to thank are those who were in the Point of Care System Design Laboratory (POCSDL) with me for my Masters studies and all the help and knowledge they imparted to me throughout this process.So to all, a sincere, "Thank you."v Contents viii 4.15 Designed System Results (Filtered) -O1 4.16 Designed System Results (Filtered) -O2 5.1 Occipital Lobe Electrode -Comparative Result 5.2 Occipital Lobe Electrodes -Acquired Result 5.3 FP1 EMG Events -Comparative Result 5.4 FP1 EMG Events -Acquired Result 5.5 TI HRM Laptop Application C.1 FP1 Electrode Filtered -Eye Blink Events C.2 FP2 Electrode Filtered -Eye Blink Events C.3 FP1 Electrode -Eye Blink Events C.4 FP2 Electrode -Eye Blink Events ix List of Tables 2.1 Data Rate(s) 3.1 ADS1299 SPI Commands 3.2 ADS1299 Registersthe-art EEG platform.In this thesis, we will use the g.USBamp 3.0 system [3] manufactured by g.tec Inc. as a baseline system for EEG signal capture.The g.USBamp allows for up to sixteen channels of EEG data acquisition per USB amplifier.This system also provides 24-bit resolution and will simultaneously sample all channels up to a maximum sampling rate of 38.4 kSPS.The design described in this work provides a replication of result quality on up to eight EEG channels, with improvements which make the designed system much more modular, portable, and adaptable, thus making this system an improvement on the basic system structure as a whole.