This is a testing site only. See the live Public Lab site here »

Balloon Telemetry Kit

This kit was created as a means to improve the georeferencing of images captured using balloon mapping. This kit is based around the open-source Arduino mircocontroller. Utilizing a GPS receiver, barometric sensor, three-axis accelerometer and data logger, this module allows for the synchronization of data with images captured from a Canon camera running the CHDK. By utilizing the USB remote function of the CHDK software the camera can be triggered in sync with the logging of the sensor data. Along with the georeferencing capabilities, this kit captures the position of the camera in relation to the ground plane. This is done by capturing the x/y rotation of the camera with the accelerometer. Parts List: ADXL335 Accelerometer Barometric Pressure Sensor - SCP1000 OpenLog data logger Arduino Proto Shield GPS Module Arduino Board Sample log data: lat,long,Date(yyyy-mm-dd),Time(hh:mm:ss:cc),alt(m),course,speed(knots),speed(mph),speed(mps),speed(kmph),pressure(Pa),baroAlt(m),xAxis(deg),yAxis(deg) 40.76892,-73.94951,2011-1-21,21:43:15:0,39.50,227.29,0.00,0.00,0.00,0.00,100297.75,85.86,-57,-80 Arduino code available here Here is a quick test of image rectification using the accelerometer data. This picture shows some data (GPS elevation, barometric altimeter) being transmitted live from the module over the Passaic River to the laptop, November 13, 2010: We are considering using this method to write this information into the EXIF for each image. Comments from mailing list: Great idea for balloon and kite mappers, having a single small device to hang there would come extremely useful. When I needed to log GPS data for a flight recently I needed two bulky devices: the camera, and the GPS, and they weren't synchronized. The CHDK synchronization is a very promising way to do that. And with the arduino pins accessible the device can probably be easily extended with further sensors is necessary. (It feels still slightly redundant that we can't have the camera on the same board, wouldn't that be great? But technically image processing is a whole another step higher than arduino, and CCD sensors are difficult to get hang of) Looking forward to see the telemetry kit in use! My only doubt is about the reliability of accelerometer measurements on a flying object. Attitude estimation is going to be difficult due to the amount of movement and non-gravity acceleration. One solution to this would be to include a 3-axis gyro in addition to the accelerometer. Sensor sets composed of a gyro and an accelerometer can give quite reliable results by compensating for each other's error characteristics. The compensation involves some maths, but it can be executed on an Arduino board and there are several successful projects using this methods. MultiWii is one example, where a $20 set of popular Nintendo Wii controllers can be used as an arduino-compatible tiny sensor board. It's similar to the sparkfun ADXL board but contains gyroscopes and MultiWii provides an arduino library for calculating attitude using kalman filters. -- balrog...

Author Comment Last activity Moderation
guyshalem " Amazing! Thanks for sharing " | Read more » over 3 years ago
mathew "Micmac's new site: " | Read more » over 4 years ago
mathew "That documentation has an interesting note, on page 34, that MicMac can be used to calculate Orthoimages directly, without bringing it into GDAL or..." | Read more » over 8 years ago
mathew "Nice! I hope it goes well. I just started some experiments with the Python Photogrammetry Toolbox myself: http://arc-team-open-research.blogspot...." | Read more » over 8 years ago
jart "I managed to find an english version of the users guide. I will report back when I have some results." | Read more » over 8 years ago
cfastie "Pat, here are some thoughts on two issues: A camera stops recording during a flight: I have had similar experiences, on three or more flights, of..." | Read more » about 10 years ago
warren "Also, if you're interested, you might consider merging your work (when you feel ready) with the existing balloon telemetry kit tool page, which has..." | Read more » about 10 years ago
warren "Oh, Fritzing link: " | Read more » about 10 years ago
warren "Great progress, very cool. One way to share circuit diagrams in a very legible way is to create them in Fritzing, a free, open source circuit desig..." | Read more » about 10 years ago
warren "To share, feel free to upload the .zip, but you're right, once that's done we could try to unpack it a bit and create some images and wiki pages fr..." | Read more » about 10 years ago
patcoyle "Tonight I took a few minutes and was able to get the Canon A495 triggering with the CHDK circuit and taking photos that looked reasonable, given th..." | Read more » about 10 years ago
patcoyle "Thanks Chris, I appreciate the encouragement. I just checked and the A495 was in Program mode. I was using it with rubber band over shutter in con..." | Read more » about 10 years ago
cfastie "Pat, Thanks for posting this. I agree with Jeff that the automatic modes in Powershots are incredibly useful for getting good results with no frett..." | Read more » about 10 years ago
warren "Actually i think that dual-camera wiki section on shutter priority was Chris F's -- it's a good idea but personally I usually leave it on auto, and..." | Read more » about 10 years ago
patcoyle "See: for related video " | Read more » over 10 years ago
warren "Wow, pat -- if you can get this data added as exif tags to the photos, ill write an auto importer to mapknitter! Isn't there a batch program to add..." | Read more » over 10 years ago