For Pilots (Using this in actual flight), please see important note at end
Version 5.1 is ready!- Optimized for the iPhone 6 and 6 Plus! - Oct 6/2014
GYROSCOPE TECHNICAL NOTES:
You are probably wondering, why does the ground mode gyroscope work so smoothly and accurately, and air mode is much more difficult:
Ground mode uses what Apple calls "Sensor Fusion", which is not only the gyroscope, but also the accelerometer and other logic, it is very heavily weighted toward gravity. Of course when sitting on your couch at home, Gravity can be depended upon, and thus, any gyroscope drift can be easily subtracted away by using gravity as the base.
Air Mode: After extensive testing in Airplanes I quickly found that ground mode was useless in the air, it would always show wings level, of course as a pilot you know why, Gravity "seems" to be pointing to the bottom of the aircraft during turns, due to the combination of forces in an aircraft turn.
I then moved to using the "raw" gyroscope output for air mode, no choice. The issues here are many. The gyroscope chip in the iDevice has a huge amount of static drift (the drift when its sitting perfectly still). I need to not only remove this static drift, but also deal with normal gyro drift while flying. This proves difficult, partly because the built in compass (one of my base points) tends to freeze up quite often in flight. I am working actively on improving the methods of removing the drift.
Currently some pilots have seen the app show a turn and then reset to wings level (even though the aircraft is still turning). This is because my "reset" code thinks the gyro drift needs to be removed. This can be controlled with the slider bar (move it more to the right). I am also looking at ways to improve this, and get rid of the slider bar over time and have an auto correcting system.
In summary, I still have work to do, but I promise to keep updating this app until it is the best I can possibly make it.
The internal Gyro chip is sensitive to engine/prop vibration. Attempt to mount it with the least possible vibration.
iPhone Gyroscope Aircraft Attitude Indicator (a.k.a Artificial Horizon). This app uses the "real" Gyroscope built into the iPhone 4, so it is much more accurate than the older apps without Gyro access (accelerometer only).
I am an instrument rated Airplane Pilot and a Helicopter Pilot, I designed this app for a fun demonstration of how flight instruments in a real airplane work. My goal is to also have this work well in actual flight (see notes below).
Even for non Pilots its a blast! and kids will love to turn the iPhone in every direction and watch the sky and ground roll and pitch around!
Runs in landscape mode for the full size screen and motion, high resolution retina display graphics!
Also great for flight school instruction and demonstration of the iPhone gyroscope.
Note for Pilots : If you notice in flight that the app shows a turn, then goes back to wings level (while the aircraft is still turning), move the slider bar more - or all the way to the right. In order to remove the gyro drift, I use the compass changes to slowly go back to wings level, the compass tends to freeze up in the iPhone, and I am actively working on a solution for this. Currently this reset is controlled by the slider bar.
Although I am flight testing and fine tuning the air mode code each weekend (We have a Mooney M20c Aircraft for testing this app), after finding the "stock" gyroscope code did not work in aircraft (always read wings level even with gyroscope output), it must be clear this is still NOT FAA APPROVED and should not be depended upon for flight. As a fellow Pilot, I am also excited about having the iPhone 4 gyroscope work in airplanes, however, for now its experimental use only. I am improving the operation in the air at every release, and its getting better, but still needs work. I intend to keep working on it until its the best it can possibly be in the air.
For non Pilots, or Pilots using this for ground instruction, it works flawlessly with the Stock Gyroscope on the ground. And is perfect for instruction or fun. The stock iPhone Gyroscope code is smooth as silk on the ground, make sure you do not use "AIR MODE ON" for ground use/instruction. Air mode will seem erratic on the ground, it depends on the G forces and compass changes in flight to work.
What's New in Version 4.0
- Bug Fix: Fixed problem where display would reset to wings level even as aircraft was still turning, finally tracked down and fixed this one!
- Display redesign, now matches a real electronic display movement. Turn circle now is fixed with arrow and only moves right and left not up and down, which would cause it to go off the screen display at times before.
- Big improvements in gyro drift control in flight mode, much faster response back to wings level after an aircraft bank.
Click HERE for the latest flight test video in our airplane. As you can see, the app is getting better. The vibration effect is low since I am hand holding it. I found a great Ram Mount made just for the iPhone 4 with a strong suction cup mount, however, it is more affected by the aircraft engine vibration.