DroidPlanner has just been updated with an incredible feature that comes very close to "one-button 3D mapping" with ArduCopter. Here's a quick tutorial on how to use it to create a mission that autonomously takes off, circles a building taking pictures of it and lands, capturing all the imagery you need to stitch together a 3D model like the above. This model was taken with a 3DR Iris and GoPro camera in just one circle and stitched together with Autodesk Memento/ReCap.
(Don't forget you can now do this via Bluetooth with your Android phone or tablet, in addition to the usual 3DR long-distance radios.)
1) In the Edit screen, hold down the trash can icon, which will clear any previous mission you had and auto-create the first waypoint, which is an auto-takeoff. Then tap the Add Waypoint button (the top one with the "+") and tap the center of the structure you want to 3D-map:
2) Tap on that new waypoint and in the drop-down menu, select "Circle". This will tell the copter to do a single circle at the default altitude (20m) and the default radius (10m), with the nose of the copter and camera always facing into the center of the circle. If that's what you want, you're done!
3) (Optional) If you want it do to do multiple circles at the same altitude, change the "Orbits" number in the menu below. If you want it to do multiple circles at different altitudes (to give the stitching software a range of views), tap on Advanced and change the Steps number to the number of circles you want, with the Altitude Step being how much higher each circle should be over the one before:
4) At that point, you can either launch the mission and when it's done it will loiter, waiting for you to manually land, or you can add more more waypoint to autoland (triangle waypoint icon below). If you're done, don't forget to press Send Mission to send it to the copter!
5) If you want the copter to circle with a larger or smaller radius, select Parameters
In the Parameters list, scroll down to CIRCLE_RADIUS and change it whatever value you'd like. (Note that in the screenshot below there's an error: the units are in centimeters, not meters. So 2000 is 2000cm or 20m. That will be fixed in the next push)
When you're done changing that, remember to Write the parameters to the copter:
6) Now that you've finished the mission, set your onboard camera to take a picture once per second in stop-motion or "intervelometer" mode (I use a GoPro Black with my Iris, which works great, but you can use any camera that has this mode). Don't forget to start the camera!
7) Now switch your copter to Auto mode and nudge the throttle up a bit. The copter will take off, fly to the structure, circle it at the altitude and number of times you selected, and automatically return and land at your feet! Mission accomplished!
Some safety notes:
- Watch out for trees and other obstacles! Make sure your first circle is above any trees or other things that might be in the path of the circle
- Make sure your radius is at least twice the distance from the center to the edge of the structure. You want to have at least ten meters clearance from the structure at all times
- If you're doing an autolanding, make sure you've got plenty of room for the landing and no obstructions on the route home. If you can't ensure that, do the landing manually.
- Don't plan any mission where your view of the copter will be obscured. You must be able to take over manual control if it looks like your mission will take the copter into harm's way
Once you've finished the mission and acquired the imagery, you'll need to use stitching software or a cloud service to turn it into a 3D model. Autodesk offers some good free choices for that:
- 123D Catch. Quick and dirty. This won't make the best model, but it's easy, works most of the time, and has a good web viewer so you can share the 3D model with anyone. Mac, Windows or Web
- ReCap 360: This offers better renders, but it can be hard to get it to reliably generate a model. Web
- Memento: This is beta software, but it works great for me and is my go-to tool for high-quality renders and a very easy-to-use interface. You have to join the Autodesk Labs program to use it (that's free and open to all), but it's well worth it for this gem. The only downside is that it's Windows-only so if you're a Mac user like me you have to dual-boot or run Windows in a VM
In the next version of DroidPlanner, the interface to change the altitude, radius of the circle and the number and step-distance of each orbit will be improved to a simple "point and drag" feature, which is very intuitive. Basically, you'll just point at the structure you want to 3D map, drag the circle so it's well outside the structure, drag a slider for the altitude and press go. One-button mapping!