Brain Wave Group 1

Final PresentationJames LinSon Phan

Michael Oduselu

Purpose Research Thought Controlled

Applications Observe how mind control can be

used Open new means of communication Enhance quality of life and mental

well-being

Potential Applications EEG Biofeedback

Control brain rhythms Computer Control & Communication

Thought controlled systems Entertainment & Virtual Reality

Brain influcenced music and graphics Adaptive Virtual Worlds

Applications Cont. Education and Research

Brainwave experiments and labs Military and Commercial Applications

Monitor health and concisousness (NASA)

Controlling planes (Air Force) Monitor consumer reactions to Ads and

Products

Research Background John Chapin

Trained 6 rats to push a lever Computer established pattern for

pushing lever Mice pushed lever with thought

Gloria Calhoun Used brainwaves to pilot a flight

simulator

EEG Stands for Electroencephalogram Records bioelectric activity of brain Monitors Frequencies from 0.5 to

20 Hz Dependent on brain activity

Age, arousal level, sleeping state, cerebral dysfunctions

EEG Machines Available Brainmaster

2-channel general purpose brainwave monitor

Performs data storage, retrieval, real-time signal processing, display, and feedback

WaveRider Jr Has Audiovisual feedback More integrated and configured for easy

use but less sophisticated

EEG Machines Cont. POD

EEG feedback machine Used to improve self in areas ranging

from studying to golf ProComp

8 channel machine capable of EEG, EMG, EKG, skin conductance, temperature, heart rate, etc.

Expensive

Goals Tackle first task of reading

brainwaves Research and design EEG circuit Assemble EEG circuit Read brainwave on oscilloscope

Design Objective Build EEG Circuit

Get parts Use BrainMaster schematicsd

Test/Optimize EEG Test for heartbeat Test for brainwave Solder final circuit

Previous Design

Amplifier didn’t work

Revised Design

First step: EEG Monitor

Amplifier Schematic

Analysis Objectives Understanding Circuit

• Brain-Master Schematic• Part Functions

Implement Circuit in P-spice• Ideal Op-Amps• AD620• OP90

Simulate and Examine Result• Input and Output• Total Gain

Implement Circuit in P-spice

Simulate and Examine Result

0

1

2

3

4

5

1 10 100 1000

The Output Voltage

Voltage

Vo

lta

ge

Frequency

Continued…

0

5000

1 104

1.5 104

2 104

2.5 104

1 10 100 1000

Total Amplifier Gain

Gain

Ga

in

Frequency

Specifications Type: differential Gain: 20,000 Bandwidth: 1.7 –

34 Hz Input Range

200uV Output Range 4 V CMRR >100dB

Other components Midpoint Voltage circuit

Other components Clean power source

Navigation: Waves vs Emotion

Heartbeat Test Results Breadboard

circuit measurement of heart beat Second figure

shows a close up. Compare with

EKG

Assemble working circuit Solder circuit

together for better performance

Cleaner signal with better electrodes and pads

Flat signal = good sign

Signal from head Tested signal to

amp by biting down.

First capture shows one bite.

Second capture shows 3 bites.

Measure Brainwaves Results from head

show fluctuating signal between 3 and 30 Hz.

Wave compared to Brainmaster screenshot.

Brain results cont. Waves look similar Need to use filtering

to isolate frequency energy of wave in a specific time.

FFT Response FFT shows that range

of frequncies is 0 – 30 Hz

Closer insepection shows a consistant frequency spike around 10 Hz.

Frequency corresponds to Alpha waves at front of head.

Muscle induced response First capture

shows response of raising eyebrows once.

Second capture shows two eyebrow raises.

Results continued Capture shows

signal created by a hard blink

Conclusions EEG amplifier worked well in

collecting signals from the head. Muscles signals were far easier to

see and create. No training involved. Application such as a vehicle

requires instantaneous responses which muscle signals may be better suited for.