ElectroencephalogramControl System
By
Joseph Fletcher
Ryan Lacroix
Gary Stroup
Kenneth Sugerman
Bioengineering 175- Senior Design
University of California, Riverside
February 3, 2010
Executive Summary
This project consists of using anelectroencephalogram (EEG) to measure brain wavesto be used as a control system. The control system will allow fortwo independent axes to be controlled.
1 Introduction
1.1 Background
A human’s neurological system transmits information through electrochemical pathways. Consequently, these electrochemical events can be monitored from the surface of the skin using electrodes connected to an electroencephalogram (EEG). Because the occurrence of various types of signals read by the EEG can often be controlled consciously by a subject, this phenomenon has been invoked in a wide variety of application; including wheelchair control by paraplegics, video games, light dimmers, and computer mouse control.
1.2 Purpose
The proposed design involves reverse engineering already existing single dimension EEG controllers to produce a two dimensional controller for widespread application. Previous attempts at projects such as this have involved extensive training by the subjects or have been quite expensive. The goal here is to use already existing controllers to significantly reduce cost and, by determining ideal placements for electrodes, reduce training times. Ultimately, this project will allow for design of products for wide scale consumer application.
1.3 Previous Work Done by Others
1.3.1 Products
1.3.1.1 Force Trainer
Electrodes on the skull read brainwaves, mostly beta waves. The brainwaves are interpreted and transmitted wirelessly to tower and the fan blows air and causes the ball to rise.
1.3.1.2 Mind Flex
Like the Force Trainer, the Mind Flex reads brainwaves and transmits it as a signal to the main console which then activates a fan to elevate the ball. The greater you concentrate the more power is delivered to the fan and thus the ball rises higher.
1.3.1.3 Work Done by Researchers
Title:Scientists Develop Helmet to Control Toy Vehicles via Brain Waves
Applied to:
-use for people in wheelchairs and prostheses
-diagnostic work
-video game controller
To steer the vehicle:
- the person wearing the helmet views a screen with two chessboard patterns that
blink at different frequencies.
- Concentrating on the left or right chessboard will move the vehicle in that
direction. If the person doesn’t focus on either pattern it will travel straight ahead.
Title: A real-time EEG Based Remote Control of a Radio Shack Car
- used Labview digital IO
- used mosfets instead of switch contacts
strobe stimulus: light intensity altered
-analyze mu rhythms and measurement from visual cortex
-quiet and relaxing environment
-Sinusoidal modulated video files
Title: Continuous Brain-Actuated Control of an IntelligentWheelchair by Human EEG
-3 subjects were asked to mentally drive wheelchair to 3 locations using 3 mental commands
-Turn left, turn right, and move forward
-10 trials per target
- Results show that mental control of wheelchair can be achieved
1.3.2 Patents
United States Patent #5638826
Wolpaw, et. al.
June 17, 1997
The invention contemplates that brain waves, preferably mu rhythm waves of an individual, can control a cursor on a video monitor or other device in the environment
United States Patent #4928704
Hardy
May 29, 1990
A biofeedback method and system for use to train a person to develop useful degrees of voluntary control of personal electroencephalogram (EEG) activity.
United States Patent #4013068
Settle, et. al.
March 22, 1977
An EEG activated control system responsive to voluntarily or consciously produced EEG signals encoded to correspond to a plurality of commands.
2 Project Description
2.1 Objective
The objective of this project is to develop a remote EEG controller system with twoindependent axes of control. The goal is to minimize training time and have reproducible results.
2.2 Design Specifications
Specifications# Independent Axes / 2
Response Time / 1000ms
Power Source (EEG reader) / 6V (4 × AA batteries)
Power Source (Controller) / 6V (4 × AA batteries)
Three levels of control per axis / off(0mV), medium(1mV), and high(2mV)
Size (EEG reader) / 2” × 3” × 1” + Electrodes
Size (Controller) / 3” × 3” × 2” + Leads
Training Time / <15min
Number of Electrodes / 4 (2 references)
Signal / Continuous
WirelessRange / 25 ft
2.3 Methods
The first part of the development of the prototype will entail the disassembly of two previous EEG controlled devices: Mattel’s “Mind Flex Game” and Milton Industry’s “Star Wars Force Trainer.” These utilize EEG controls in one dimension to determine the strength of fans intended to lift a ball along the vertical axis to a particular height. These devices will be reverse engineered to understand the mechanics relevant to their function including determining which brainwaves are read by these devices and comprehending their circuitry. This will then be manipulated to suit our needs. This portion of the project will be performed with the aid of an oscilloscope and breadboard with National Instruments ELVIS software.
The second part entails the determination of which portions of the brain could be appropriate for control of two axes. These portions of the brain should enable easy control with limited training time in regards to brainwave activity intensity and should be controlled independently. We must also determine if there is continuous control or if signals are time dependent. We will utilize an EEG as well as consult with faculty in the psychology department at UCR.
The final portion of the project would be the demonstration of implementation of our EEG controller. This will be demonstratedusing aremote controlvehicle. Further demonstration of the control system might be applied to a wheelchair if time allows.
3 Budget
The estimated required materials for the project
2Star Wars Force Trainer$99 eaProvided by Dr. Park
2 Mind Flex Game$99 eaProvided by Dr. Park
1Oscilloscope$--Provided by Dr. Park
1Multimeter$--Provided by Dr. Park
1Pre-amp$--Provided by Dr. Park
1Soldering and supplies$--Provided by Dr. Park
1Remote Control Vehicle$50
25Electrodes$50 package
1EEG$2000Provided by Dr. Seitz
1Elvis II platform by NI$11000Provided by Bioengineering Dept
1Elvis Breadboard and parts$50
1Lab View software$--Provided by Bioengineering Dept
-Wires, clamps, etc$25
Total$175
The total estimated cost is $175 which excludes the items provided by Dr. Park’s lab and Dr. Seitz. The prices of the products on the market that are roughly similar are about $100. Where from our estimation that the prototype will be 35% of our cost is $61.25. This is about 40% less than the products that are in the market. The products that are on the market can not be fully compared to our product because they are much simpler in design.
4 Proposed Time Line
Milestones Proposed date of completion
Reverse Engineer Pre-existing EEG Controller3/14/10
Determine Electrode Placement5/16/10
Demonstration of Control system6/4/10
Gnatt Chart
5 References and Sources
Dr. Hyle Park Assistant Professor, Bioengineering
A211 Bourns Hall,Riverside, CA92521
Hong Xu, Development Engineer in Bioengineering at UCR
A217 Bourns Hall,Riverside, CA92521
Phone: 951-827-7235
Dr. Aaron Seitz, Assistant Professor, Psychology
3101 Psych,Riverside, CA92521
Phone: 951-827- 6422
Galan, F. et al. “Continuous Brain-Actuated Control of an Intelligent Wheelchair by
Human EEG”. ftp://ftp.idiap.ch/pub/papers/2008/galan-grazBCI2008-2008.pdf.
Provost, Sheldon, J. Lucas McKay. “A real-time EEG Based Remote Control of a Radio
-Shack Car”.
The Local. “Scientists develop helmet to control toy cars via brain waves”. Science &
Technology. 19 Jun 2008.
6 Conclusion
The product produced will be an EEG control system that can be independently controlled in two dimensions. This device can then be attached to any device that a consumer would choose using two electrical leads to allow that device to be controlled hands free. Application could include moving a light source around for a dentist or surgeon, prosthetic control for a paraplegic, or a wheelchair.