Chris Nafis Projects

When I'm not working at GE Global Research, I enjoy my family, boating, skiing, biking, working on our 1833 house, and a ton of other things!

Bike Generator

I worked with an elementary school teacher to build a bike generator to help the kids explore the environment, conservation of natural resources, and electricity generation

Weatherstations

I have built several weatherstations. Currently I have a wireless Davis Provantage 2>. The data is posted to WeatherUnderground ( KNYREXFO1 [barn roof] ), the Citizen Weather Observer Program ( CW1411 [barn roof] , CW3725 [garage roof]) , CBS6 WeatherNet6 , StrikeStar , and Boltek Lightning Sites .

Rabbit Processor based 1-Wire Weather station

Here's a Rabbit Semiconductor Processor based weatherstation that uses 1-wire sensors ( version 1, version 2). It displays the weather information locally on an LCD display and posts it's weather data to the WeatherUnderground and CWOP.

Siteplayer based weathervane

Here's a NetMedia Siteplayer ethernet web server based Weathervane.

Measuring Snowfall and snow depth

I'm interested in low-cost sensors that automatically measure snowfall or snow depth. I've developed several prototypes:

1-wire DS2450 based IR snow depth sensor using Sharp GP2D12 (prototype 1)
1-wire DS2438 based IR snow depth sensor using a Sharp GP2D12 and a photodiode to detect saturation (prototype 2)
1-wire DS2438 based IR snow depth sensor using a printed circuit board, Sharp GP2D12, and a photodiode (prototype 3)
Rabbit semiconductor based ultrasonic snow depth sensor using a thermister to measure temperature. I was a little disappointed with the performance last year. The system accuracy was +/-1 inch. I think the drifting was due to the thermistor temperature sensor. I need to rebuild the system using a better temperature sensor.

Water Level Detector

Here's a 1-wire IR sensor to measure water level

Solar Radiation Sensor

Here's a 1-wire solar radiation sensor based on the DS2438.

Lightning Strike Detection

Lightning detectors are available from Boltek. Lightning strike counters kits are available from Hobby Boards. Unfortunately the Boltek range estimations are not that good. I'm interested in combining the bearing information from different locations to better locate the strike locations. I've put together several applications to help display the strike locations.

In the NorthEast US, it collects lightning strike data from Boltek Nexstorm users and overlays it on current visible and IR satelite images. Vectors are drawn for each station. This helps understand where the storm actually is (Boltek systems have a problem with reporting strikes 180 degrees out of phase).

Astrogenic systems (makers of NexStorm) has now come out with an application called Strikestar that combines data from Boltek NexStorm users and triangulates lightning strike locations.

3D Scanners

I'm interested in building low-cost 3D scanners that can make a digital model of a real objects. I try to keep track of the different 3D scanning and measurement technologies.

Community Service

Won GE Phillippe Award for outstanding volunteer service
Built weather stations at Schenectady High School, Berne-Knox-Westerlo High School, and Middleburgh High School.
Demonstrated feasibility of wireless laptop lab for Tesago Elementary School since they were losing the space for their computer lab.
Developed a distance learning environment for kids with cancer.
Built a computer lab and networked the classrooms at Doane Stuart School.
Built a computer lab and networked Okte Elementary School. Helped the teachers integrate local history into their classes using a Virtual Field Trip
Built a playground for the An-Nur Elementary School
Wired Oneida Middle School to provide all sixty classrooms with Cable TV / Internet access. Watch the TV Commercial describing the project.
Built Schenectady Carver Community Center playground.
Repaired Schenectady Animal Protective Agency buildings

Selected Publications

Automated 3D IR defect mapping system for CZT wafer and tile inspection and characterization (Conference Proceedings) Authors: Yi Liao, Esmaeil Heidari, Gil Abramovich, et al. Published: 14 Sep 2011
Andreini, K.; Tkaczyk, J.E.; Tan Zhang; Williams, Y.Z.; Nafis, C.; Abramovich, G.; Harding, K.; Bednarczyk, P.J.; Chen, H.; Bindley, G.; McKenzie, J.; Ragothomachar, B.; Dudley, M.; Low-signature Cadmium Zinc Telluride CZT defect inspection by IR, ultrasound, etch pit density, and x-ray topography Nuclear Science Symposium Conference Record (NSS/MIC), 2010 IEEE
G. Abramovich, K. Harding, S. Manickam, J. Czechowski, V. Paruchuru, R. Tait, C. Nafis, and A. Vemury. Mobile, Contactless, Single Shot, Fingerprint Capture System. In Proc. SPIE, volume 7667, 2010.
Method for evaluating compatibility of commercial electromagnetic (EM) microsensor tracking systems with surgical and imaging tables (Conference Proceedings) Authors: Christopher Nafis, Vern Jensen, Ron von Jako Published: 31 Mar 2008
C.A. Nafis, V. Jensen, L. Beauregard, P.T. Anderson, "Method for estimating dynamic EM tracking accuracy of Surgical Navigation tools"; ,SPIE Medical Imaging Proceedings, 2006
C.A.Nafis, N.R. Corby, "Reducing Measurement Blunders Using Images", CMSC, 1998
C.A.Nafis, N.R. Corby, "Combining Laser Interferometer and Photogrammetry Measurements", CMSC, 1998
N.R. Corby, R.A. Hogle, C.A. Nafis, "Signal Processing and Acquisition Challenges in Real- Time Magnetic Source Imaging Systems", Computer-Based Medical Systems Symposium, 1994
N.R. Corby Jr., C.A. Nafis, "Augmented Reality Telemanipulation System for Nuclear Reactor Inspection", SPIE ,1994
P.W. Lorraine, W.T. Hatfield, C.A. Nafis, "Application of Ultrasonic Phased Arrays to Inspection of Plastic Pressure Vessels", Review of Progress in Quantitative NDE ,edited by D.O. Thomson and D.E. Chimenti, Plenum Press, New York, 1994
W. Lorensen,H. Cline,C. Nafis,R. Kikinis,D. Altobelli,L. Gleason, "Enhancing Reality in the Operating Room", Visualization '93 Proceedings ,IEEE CS Press, 1993