Public Lab Wiki documentation



Balloon Telemetry Kit

This is a revision from May 07, 2011 19:52. View all revisions
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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: a high point

We are considering using this method to write this information into the EXIF for each image.