NOTICE: This is a draft document and in the process of being written. It is incomplete and subject to change at any time without notice.
In this post I share my process and tools for creating HUD overlays on a flight video. Here is a quick overview of the process: (1) Calibrate your camera, (2) Extract the roll rate information from the flight video, (3) Automatically and perfectly time correlate the video with the flight data, (4) Render a new video with the HUD overlay.
Blending real video with synthetic data yields a powerful and cool! way to visualize your kalman filter (attitude estimate) as well as your autopilot flight controller.
Conformal HUD Elements
Conformal definition: of, relating to, or noting a map or transformation in which angles and scale are preserved. For a HUD, this means the synthetic element is drawn in a way that visually aligns with the real world. For example: the horizon line is conformal if it aligns with the real horizon line in the video.
I make thousands of mistakes a day, mistakes typing, mistakes coding software, mistakes driving, mistakes walking, forgetting to order my sandwich without mayo, etc. Most of the time they are immediately obvious — a red squiggly line under a word I mistyped, a compiler spewing an error message on line #42, a stubbed toe, my gps suggesting a u-turn at the next intersection, etc.
But what happens when the mistake isn’t obvious, isn’t noticed immediately, and doesn’t cause everything around me to immediately fail? Often these mistakes can have a long lifespan. Often we discover them when we are looking … Read the rest... >>
This is a short tutorial on an automated method to extract and geotag movie frames. One specific use case is that you have just flown a survey with your quad copter using a 2-axis gimbal pointing straight down, and a gopro action cam in movie mode. Now you’d like to create a stitched map from your data using tools like pix4d or agisoft.
The most interesting part of this article is the method I have developed to correlate the frame timing of a movie with the aircraft’s flight data log. This correlation process yields a result such that for any … Read the rest... >>
The process of mapping a pixel in an image to a real world latitude, longitude, and altitude is called georeferencing. When UAS flight data is tightly integrated with the camera and imagery data, the aerial imagery can be directly placed and oriented on a map. Any image feature can be directly located. All of this can be done without needing to feature detect, feature match, and image stitch. The promise of “direct georeferencing” is the ability to provide useful maps and actionable data immediately after the conclusion of a flight.
During the summer of 2014 I began investigating image stitching techniques and technologies for a NOAA sponsored UAS marine survey project. In the summer of 2015 I was hired by the University of Minnesota Department of Aerospace Engineering and Mechanics to work on a Precision Agriculture project that also involves UAS’s and aerial image stitching.
Over the past few months I have developed a functional open-source image stitching pipeline written in python and opencv. It is my intention with this series of blog postings to introduce this work and further explain our approach to aerial image processing and stitching.… Read the rest... >>
The ardupilot mega is a fairly capable complete autopilot from both the hardware and the software perspective. But what if you projects needs all the sensors and not the full APM2 autopilot code?
The apm2-sensorhead project provides a quick, robust, and inexpensive way to add a full suite of inertial and position sensors to your larger robotics project. This project is a replacement firmware for the ardupilot-mega hardware. The stock arduplane firmware has been stripped down to just include the library code that interrogates the connected sensors, and also maintains the code that can read your RC transmitter stick … Read the rest... >>
Today my replacement plastic parts arrived … a new canopy and a new hull shield. It wasn’t too hard to pry the old shield off, and the new part is already to slap on.
January 26, 2015
Here is a quick snapshot showing the new orange color on the engine cowls, the upper side wing tips, and also notice the tail stripes have been repainted orange (originally red.) I’m just waiting on a replacement canopy which will hopefully arrive tomorrow and I should be able to completeley reassemble the model and … Read the rest... >>
This is 1230mm (48.4″) wing span flying wing. It is powered by a 64mm electric ducted fan. It is a simple build and flies great!
Here are a couple pictures before the maiden flight (temperature was about +18F, winds were calm, skies had a medium thin overcast.)
My one gripe about the Sonic 64
Of course we buy airplanes like the Sonic 64 because they are inexpensive, quick to assemble, and fast to get out to the field and up in the air. It doesn’t hurt that they look great and are a lot of fun to … Read the rest... >>