Manned Ornithopters
 Full History

 Getting Started
 How to Design & Build
 Competition Info

 Free Plans
 History Archive
 Video Clips

 Model Kits
 Teachers Guide
 Web Site Links

 About this Site
 Join the Society
 Contact Info


FlapRate - How to Use

FlapRate is a simple, free software program that runs within your web browser. Train yourself to judge the wingbeat frequency of a bird or ornithopter with this program. Run FlapRate

Getting Started

1. You may need to download a Java plug-in to run FlapRate in your web browser.

2. The program will open in a separate window. If your computer asks if you want to allow the program to run, say yes. You should see several buttons that look like this:


3. FlapRate can display several different animations: two-wing, four-wing, and a flashing LED light. Training yourself with a variety of different animations makes it easier to transfer your skills to real-life situations. Use the pull-down menu in the upper left corner of the FlapRate display area to make your selection.


4. The "Animation" button starts the animation. To vary the speed, click your mouse anywhere in the display area: farther left for slower speeds, or farther right for faster speeds. When you release the mouse button, the wings will flap once, and the flapping rate in Hz (cycles per second) will appear beneath the animation.

5. The "Quiz" button causes the animation to run for several seconds, without showing the flapping rate. Once the animation stops, you can type your guess into the box and click the "Enter" button. Your percent accuracy will appear beneath the animation. The correct answer replaces your guess in the text box.

6. If you repeat the quiz more than once, FlapRate will calculate your overall score by averaging all of your individual scores. Your overall score is not saved when you close the FlapRate window.

More About FlapRate

1. You might be wondering why the flapping rate sometimes fluctuates while running the animation. This happens because your computer pauses to do other things while the program is running. Instead of trying to force the animation to run at a particular speed, FlapRate simply keeps track of how fast the animation is actually running.

2. The final value displayed under the animation at the end of each run reflects the average speed for the entire run. This average value is also used for scoring the quiz.

3. You might also wonder why we only show two wing positions: up and down. The animation would be smoother if we could show a multitude of wing positions throughout the flapping cycle. Unfortunately, the number of frames we can present per wingbeat cycle is limited by the program execution speed and by the refresh rate of your monitor. Suppose your monitor refreshes at 60 Hz, and the wings are flapping at 10 Hz. We could only hope to show 6 frames in each flapping cycle. Through the persistance of vision phenomenon, the rapidly sequenced frames might appear to merge, something like this:


With a real ornithopter, the wings are pretty much a blur until they come to rest at the end of each stroke. For that reason, showing them only in the extreme positions may be the more realistic option, at least at the higher flapping rates.

4. If we actually showed the intermediate wing positions at a given frame rate such as 60 Hz, you would be able to judge the flapping rate by the difference in wing angle from one frame to the next. That particular cue will not be available to help you judge flapping rates in the real world.

5. When you click the "Animation" or "Quiz" button, the animation plays for a random amount of time. This way, you can't judge the flapping rate simply by counting the total number of wingbeats.

6. I've added a new feature, which provides wingbeat sounds to match the animations. This additional sensory information might make it easier to judge the flapping rate. However, you can turn the sound off if you want to work on your ability to judge flapping rate based on the visual stimuli alone.