Montgomery SM, and Laefsky AM. 2011. Biosensing. Make26: 102-111
Mass-market magazon article in Make magazine. Contains plans for a “Truth Meter” based on electrodermal responses. Contains instructions for DIY sensors and amplifier. Also includes instructions for hacking a Mattel Mindset for wireless EEG display. Clearly written and illustrated for the novice.
Chien C, Jaw F. 2005. Miniature ultra-low-power biopotential amplifier for portable applications. Biomedical Engineering – Applications, Basis & Communications 17: 48-50.
Includes schematics. The design of this amplifier allows the filter to be cascaded as the final element, allowing alternative filters to be substituted, filters more appropriate for other biopotentials.
McGuire D, Buetow J. 2006. Using biopotential amplifiers in high school science.
Includes construction plans.
Wang J. 2010. Design of an analog front-end for ambulatory biopotential measurement systems. Master of Science Thesis. KTH. www.kth.se
Spineli EM, Martinez M, Mayoski MA, Pallas-Areny R. 2004. A novel fully differential biopotential amplifier with DC suppression. IEEE Transactions on Biomedical Engineering 51:1444-1447.
Quite theoretical, aimed at electronics engineers, and definitely not a DIY source for the beginner.
“Let’s build an ECG amplifier” Course protocol from a course offered at one time at Oxford. Like much material on the Web, it’s not possible to provide more of a context than that. As a course protocol, there is good documentation, theoretical background, and clear instructions taking the reader through the construction of and ECG amplifier. The signal is displayed on an oscilloscope, but the 0V to 5V output would suit it to an Arduino board.
Found at: rpw.chem.ox.ac.uk/ECG%20etc/ECG%20amplifier.doc
“Small 2-Lead ECG Analog Frontend Breadboard Compatible”
Found at: http://wish.seeedstudio.com/wp-content/uploads/2010/09/ECG2_AM1-DataSheet.pdf
Description of an ECG amplifier module built on a printed circuit board with instructions for interfacing it with battery, electrodes, etc. Fairly technical, and probably not for the beginner. But good theoretical background and a good paper to read for insight into the electronics involved.
MettingVanRijn, A. C., Peper, A. and Grimbergen, C. A.
Amplifiers for bioelectric events: a design with a minimal number of parts.
Found at: http://www.biosemi.com/publications/artikel7.htm
A publication found at the BioSemi website. BioSemi is a business that sells products for research electrophysiology. It was founded by medical electronics engineers previously at the University of Amsterdam. It is not clear where this paper was originally published, It is fairly theoretical, and not a source a beginner could use to design and build an amplifier. Of interest is that BioSemi offers for download an Open Source biosignal display and analysis software, ActiView, that is based in LabView, but available as standalone versions for Windows, Mac and Linux. I have not tried the software and do not know how useable it is for non-BioSemi hardware. LabView users should be able to adapt the program for non-proprietary uses.
Danielle Smith, Shawn Purnell, & Chris Hawk
Physiological Control of a Computer Mouse
Download at (other download sources also available – search for the title in a search engine): http://www.google.com/url?sa=t&rct=j&q=physiological%20control%20of%20a%20computer%20mouse&source=web&cd=2&ved=0CFMQFjAB&url=http%3A%2F%2Fcourses.engr.illinois.edu%2Fece445%2Fprojects%2Fspring99%2Fproject37_final_paper.doc&ei=WpjsT7XXM-Sm6AH2genYBQ&usg=AFQjCNHhCRUsqTBBRPAAJF7WNDy-P53NXA
Students in an Electrical Engineering course at the University of Illinois designed a system for the use of biosignals to control a computer mouse. This is their project paper. It contains schematics for the amplifiers used (EOG and EMG), discussion of theory, and practical complications encountered in the development of the system.
João Cordovil Bárcia
Human Electrooculography Interface
Dissertation – Universidade Tecnica de Lisboa
Found at: http://arjuna.ist.utl.pt/dissertacoes/entrega/teses/55283/TeseJBarcia15Mar.pdf
A thorough dissertation on the development of a system to acquire and display electooculograms. The amplifier is fairly simple and could be built by a novice. An Arduino microprocessor is used as the A/D device, and all programming is done in Processing. Includes the biological background. I would think the amplifier and display could be used for ECGs and EEGs as well.
EB Ibarra, CA Cruz, JV Cortez, AF Ramirez, AZ Lopez
Low cost Electrooculogram Signals Amplifier
Paper submitted to the 1st International Congress on Instrumentation and Applied Sciences
Found at: http://somi.ccadet.unam.mx/icias2010/memorias/307-EB_memoria.pdf
Design and build of a basic electrooculogram amplifier, with signal displayed in a MatLab program. Interface to computer is not made clear. The design and construction of the amplifier itself are well-described.
Websites:
https://sites.google.com/site/chipstein/home-page
“Homebrew Do-it-yourself EEG, EKG, and EMG”
I have found this to be a very useful resource. Instructions are included for simple EEG, EMG, and ECG amplifiers, with both Arduino and sound card acquisition. The electronics are well described, and, as the author claims to be a neurophysiologist, there is a good discussion of the theory behind the optimal circuit characteristics for recording certain biological signals. This is the modified EEG amplifier used to record an ECG in our paper in the FUN Symposium issue of JUNE (2012), and this amplifier should be a good choice for a beginner. Simple display options and instructions are also included, although these were not used as our display options in the paper.
“DIY Biology: Not Your Mother’s Biosensor Array”
As part of the Great Global Hackerspace Challenge, Pumping Station:1 designed and constructed a biosensor array. One of the sensors was an ECG, and another measured electrodermal changes. They planned on sending the signal via Bluetooth to the Open Source program Brain Bay, but this aspect is not well-documented in their pdf. The project was based around an Arduino board. I have communicated with a couple of members of this group, and they had the goal of developing this array for use in high school education. After the contest, they seem to have dropped the project for unknown reasons. There is a lot of online material available, but it’s unfortunate that the developers seem to have moved on.
A blog of the challenge is still online here:
http://www.element14.com/community/groups/pumping-station-one/blog/2011/05/04/final-gghc-post
A pdf that has technical details of the ECG and GSR is here:
https://www.element14.com/community/servlet/JiveServlet/previewBody/29666-102-2-210821/gghc_psone_biosensor_array%20.pdf
Other technical documentation can be found here:
http://wiki.pumpingstationone.org/index.php/Biosensor_Array
A piece about the project in Make magazine is here:
http://blog.makezine.com/2011/05/12/gghc-semifinalist-profile-pumping-station-one/
https://courses.cit.cornell.edu/bionb440/FinalProjects/f2005/kwj5/index.html
“Wireless Electroencephalogram”
Development of a wireless elecrtroencephalogram by students in a course taught by Bruce Land at Cornell. Includes a good presentation of both the biology and the electronics. Includes a discussion of the different characteristics of various biosignals. Uses FM transmission from the sensors to the amplifier.
http://nuclearrambo.com/wordpress/?p=850
A simple ECG amplifier. Of note is that this one can be bought, already constructed, for $50, or the PCB can be purchased for $15. I have not tried this one, and I do not know how well it works. Designed for a soundcard input, it may work with a microprocessor board if the output voltage is appropriate.
http://www.swharden.com/blog/2009-08-14-diy-ecg-machine-on-the-cheap/
“DIY ECG machine on the cheap”
Part of the swharden blog, the blog of an electronics/computer hobbyist with an academic background in biology. This is a description of a very simple ECG. Better for helping to understand the basics of the electronics behind construction of an ECG amplifier than actually providing a useful ECG amplifier for teaching use.
http://www.cisl.columbia.edu/kinget_group/student_projects/ECG%20Report/E6001%20ECG%20final%20report.htm
“ECG Measurement System”
A student report from a course at Columbia, describing the construction of an ECG amplifier, with the ECG displayed on an oscilloscope. Fairly rudimentary, although the schematic could be used to quickly build the amplifier.
http://www.soa-world.de/echelon/2008/12/simple-ecg-amplifier.html
“Building a Simple ECG amplifier”
Another ECG amplifier built as part of a college course, in this case a Signal Processing course at the University of Applied Sciences Regensburg. Not much documentation, but a clear schematic and a couple of photos. The ECG is displayed on a USB oscilloscope.
http://www.eng.utah.edu/~jnguyen/ecg/ecg_index.html
“Homemade Electrocardiograph”
A hobbyist’s site that takes the do-it-yourself approach to extremes, using pennies as the electrodes, and a design using parts totaling about $4.00. The author includes both a page designed for those who would like to quickly put this together, as well as several pages with more of the theory and background. Signal input is through the computer sound card, and display is on a downloadable program created in Visual Basic.
http://plus1plus1plus.org/Resources/EEG-EKG
EEG and EKG (ECG) Schematics
A dual EEG/ECG amplifier. An interesting feature is that there are different inputs for recording EEGs and ECGs, and the schematics are well-documented in that they make clear what the engineering reasoning behind the distinction is. Also includes an optional modulation circuit that allows low frequency signals to be recognized by a sound card, which normally doesn’t allow frequencies lower than 20Hz through. The developer (Adam Overton) has built an aluminum enclosure for his model, and there are photographs of it available. I have not built this amplifier and cannot personally vouch for it, but the documentation appears well thought out and viable.
http://uncbme.com/RobotChicken/
“Biopotential-controlled Robotic Arm”
Includes separate schematics for amplifiers designed to record EOGs and EMGs. These UNC students aren’t interested in displaying and analyzing the biopotentials, but using them to control a robotic arm. Uses a LabView program and a microcontroller to accomplish this. The outputs of the amplifiers appear to be in the correct range to be processed by an Arduino board. Not personally tested.
http://e-gizmo.com/wordpress/?p=208
“Project: Bioamplifier”
Schematic for an ECG/EEG amplifier, outputted to an oscilloscope. Not very well-documented, but includes a digital isolation amplifier, which should, in theory, provide complete galvanic isolation for the subject. Amplifier has not been built and tested by me.
http://iftekhar-ahmed.blogspot.com/2009/10/polygraph-machine-based-on-ecg-and-gsr.html
“Polygraph based on ECG and GSR”
Blog of the development of a basic polygraph based on homemade ECG and GSR amplifiers, with signal fed though a computer sound card. Written by an undergraduate at Bangladesh University while in a Biomedical Instrumentation course. Straightforward and simple. I have not built this myself.
http://www.chris3000.com/archive/galvanic-skin-response/
“Super simple GSR Circuit”
Found at the personal website of a NYU instructor, this is an extremely simple GSR acquisition and display system. Hex nuts are used as the transducers, Complete, including schematic and all computer code (in Processing for Arduino), for both acquisition and display. Not well documented.
http://researcher.nsc.gov.tw/public/8905780/Attachment/7112618172671.pdf
“Development of an Electr-Oculography (EOG) Measurement System
A PowerPoint presentation on the design and construction of a simple EOG amplifier, constructed by students for a college course. Signal displayed on a software oscilloscope. Not well documented, and the computer interface is not indicated. The schematic itself looks fairly simple to build, and the sample oscilloscope traces are clear and noise-free.
http://123seminarsonly.com/Seminar-Reports/025/57297132-EES-EOG.pdf
“Electrooculography: a new approach”
Luis Cruz
Subtitled: “Developing a Human-Computer-Interaction method with a low budget.” The actual interface, while intriguing, is not as well-described as the amplifier itself. And may have limited use for the novice. The amplifier itself is explained well, with a very good section on the choice of filters to be used for EOG signals. The output voltage is within the range of the Arduino requirements.