Brain Wave Group 1

1
Brain Wave Group 1

• Final Presentation
• James Lin
• Son Phan
• Michael Oduselu

2
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

3
Potential Applications

• EEG Biofeedback
• Control brain rhythms
• Computer Control Communication
• Thought controlled systems
• Entertainment Virtual Reality
• Brain influcenced music and graphics
• Adaptive Virtual Worlds

4
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

5
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

6
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

7
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

8
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

9
Goals

• Tackle first task of reading brainwaves
• Research and design EEG circuit
• Assemble EEG circuit
• Read brainwave on oscilloscope

10
Design Objective

• Build EEG Circuit
• Get parts
• Use BrainMaster schematicsd
• Test/Optimize EEG
• Test for heartbeat
• Test for brainwave
• Solder final circuit

11
Previous Design

• Amplifier didnt work

12
Revised Design

• First step EEG Monitor

13
Amplifier Schematic
14
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

15
Implement Circuit in P-spice
16
Simulate and Examine Result
17
Continued
18
Specifications

• Type differential
• Gain 20,000
• Bandwidth 1.7 34 Hz
• Input Range 200uV
• Output Range 4 V
• CMRR gt100dB

19
Other components

• Midpoint Voltage circuit

20
Other components

• Clean power source

21
Navigation Waves vs Emotion
22
Heartbeat Test Results

• Breadboard circuit measurement of heart beat
• Second figure shows a close up.
• Compare with EKG

23
Assemble working circuit

• Solder circuit together for better performance
• Cleaner signal with better electrodes and pads
• Flat signal good sign

24
Signal from head

• Tested signal to amp by biting down.
• First capture shows one bite.
• Second capture shows 3 bites.

25
Measure Brainwaves

• Results from head show fluctuating signal between
  3 and 30 Hz.
• Wave compared to Brainmaster screenshot.

26
Brain results cont.

• Waves look similar
• Need to use filtering to isolate frequency energy
  of wave in a specific time.

27
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.

28
Muscle induced response

• First capture shows response of raising eyebrows
  once.
• Second capture shows two eyebrow raises.

29
Results continued

• Capture shows signal created by a hard blink

30
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.