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!

Weatherstations for Schools

I have been working with the GE Volunteers organization to build weatherstations for local schools. The hope is to get kids interested in science.

My weatherstation located in Vischer Ferry, NY
Weatherstation located at work in Niskayuna, NY
Schenectady High School
Berne-Knox-Westerlo High School
Middleburgh High School
Okte Elementary School, Clifton Park, NY

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.
I'm getting the snow sensors ready for the 2007 season. I've finally gotten around to writing software that runs on a PC and posts the data to the web. Last year I also configured a Rabbit Semiconductor processor based system that posts temperature , solar radiation, snow depth to the web (based on IR snow depth sensor). That way you don't have to tie up your PC to collect data. I've built an automated calibration rig out of an old plotter. I can put in my chest freezer to better simulate the winter environment. I'm working on calibrating the sensors and improving the data collection software. I've gotten the following sensors posting data:
- snow depth sensor # D90000005EBD5B26
- snow depth sensor # 6C00000032EEEE26
- snow depth sensor # FC00000053F86926
- snow depth sensor # 5600000032B8C926
- snow depth sensor # 6A00000053F86026
- snow depth sensor # 7D00000053FA7A26
- snow depth sensor # 300000005EBD4D26
- snow depth sensor # EB00000053FA7326 (330ohm resistor, Clairex CLD140 photodiode)

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 North America, it collects lightning strike data from Boltek systems that have Nexstorm and Lightning/2000 software. The data is overlayed on top of current visible and IR satelite images of the USA
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.