Despite significant alterations to the accessory bay and magnetometer, the drone functioned as normal, flying perfectly in position hold in both wind and rain. All original controls still functioned, and the drones compass performed remarkably well, with the I2C extension not causing any failures or brownouts. Autonomous flights and automissions worked perfectly as well, and I was able to connect the aircraft’s Pixhawk autopilot via wifi through Mission Planner software, and upload code, as well as change settings to enable sensory input to the I2C extension bus.

Discussion and Conclusion:

Although I didn’t get as far as I had wanted, this project was largely a success. Similar hacks of the 3DR drone by others have produced mixed results. There is an entire community on Facebook dedicated to sharing different ways of making this aircraft more open-source. Although people attempting a similar hack to mine have reported brown-outs to the companion computer due to the magnetometer alteration, my drone worked perfectly. My final product is relatively inexpensive, open source, and highly customizable. Once equipped with sensors, it could be used for numerous purposes. Distance sensors or Lidar could be used to map the earth’s topography, caves, or mine shafts, as in the Commonwealth Scientific and Industrial Research Organization project. Servos and thermal imaging could be used for search and rescue. However, my project’s largest strength lies in how quickly the drone can be modified and reprogrammed. For under $300, this aircraft can be used for a host of research applications, and sensors and servos can be changed from mission to mission. Over the coming weeks, I intend on attaching some servos to test the practicality of my design. If I were to perform this hack again, I would find a way to utilize the CH 8 input, and attach a frame to the bottom of the Solo for maximum part modulity. That way, sensors and servos could simply be snapped into place, making it even easier to swap out parts.