Enhance Your Technical Presentations With Animated GIFs

Determining the best way to communicate technical ideas and research results can be nearly as challenging as doing the research itself. In the last 15-20 years the availability of computer projectors, presentation software, and digital video, has enabled a far greater arsenal of data visualization techniques than ever.  However, there are still some limitations in the options most presenters choose.

On one hand, static charts and plots are very simple to produce, even with effective use of color, and lend themselves well to many formats.  However, they can show a maximum of three dimensions (and the third dimension in a flat plot can be difficult to get right), and if there is a time history of the data it can be hard to intuitively understand a plot that shows time as a spatial dimension.

On the other hand, while videos can show a much greater wealth of data, using them in a presentation can be a crapshoot. I have seen more than my share of presentations where the author embedded a video, which ultimately showed up as nothing more than a black rectangle.  Between ensuring that the correct codec and media player software exists on the presentation computer, ensuring that there is enough computing power to make the playback smooth, fussing around with what to click to get the thing to play on cue, and configuring it to play on a loop, embedding a video can be a royal pain.  To boot, videos tend to make presentations very, very large on disk.

To address these shortcomings, I offer an intermediate option–one that has the simplicity of a static plot or image, but the ability to show motion and other change with time of a short video: animated GIFs.  To be sure, GIFs cannot have sound associated, and they work best in short (<20 sec) clips.  But they have the potential to give a wide array of presentations an additional tool to effectively express results.  They show “video” in a constant loop and are compatible with all major presentation software, most image viewing software, and all major browsers (making it easy to transition from presentation to web page.)

There are several ways to create animated GIFs.  Lifehacker published a very good guide on this process not long ago, but I wanted to throw another method into the mix, one that works especially well for stitching together images of plots (for example, from Matlab).  This one uses the open source image manipulation software, ImageMagick. For this short tutorial, I will be using Linux-based commands, though I imagine that the Windows equivalents are very similar.

1. Generate the sequence of images.

For the example I use here, I used Matlab to run a simulation, then plotted the state of the system at each time stop and saved it to a *.bmp file (.png files will work just as well).

saveas(gcf,['plot',num2str(i, '%03u'),'.bmp']);

The '%03u' means that the file name will have three digits no matter what number (i.e. plot034.bmp). This is important to maintain as the converter program needs the correct format to parse the images in order.

2. Run ImageMagick

Run this command at the command line in the folder where the images from step 1 are stored.

convert -delay 20 -loop 0 plot*.bmp animation.gif

The -delay 20 argument will cause a 20 hundredths of a second delay between each frame (i.e. run the animation at 5 frames per second), and the -loop 0 will cause the GIF to loop over and over again.

Here is an example from some recent collision avoidance work I’ve been doing:

scenario5

Remember, though–the more frames you put in, the larger the file.

Elementary School . . . of Engineering?

While visiting James Fallows’ website writing this book review, I came across his article (oops, I guess his wife wrote it) about one of the coolest things I’ve heard of in a while: an elementary school intentionally geared toward teaching engineering.

It seems that at J. Whittenberg Elementary in Greenville, SC, they have fully integrated technology and problem solving and, yes, engineering into nearly every facet of their curriculum.  I am in awe, and severely tempted to move to Greenville.  If only Clemson had any faculty positions opening up in the next year or two . . .

America’s Tiniest Engineers: Report from Greenville, South Carolina | The Atlantic

Book Review: China Airborne

A month or two ago, I found a copy of James Fallows’ 2012 book China Airborne: The Test of China’s Future on my desk.  My advisor had just read it and, knowing my interest in China (evidenced here, here, here, here, and here), thought I would enjoy the read.  Notwithstanding the occasional dry bits, I did.

The synopsis:

There is a lot of information in this book–culture, history, politics, and technology woven together in a way that helps to make sense of China’s ambitions in the aerospace industry.  I’ll try to hit some of the main themes:

  • China’s massive economic growth in manufacturing, building, and services is also carrying over to their aerospace/aviation industry, albeit with not quite as much success.
  • Despite our mental picture of China as a closed country that is now just opening up, we (the US) have a history of trade and collaboration with China/Chinese people in aviation (see the Wikipedia entry for Wong Tsu.)
  • The Chinese have had somewhat haphazard development of airports and factories–some places with fantastic air terminals, but no one to use them, no fuel and no spare parts on hand.  Massive factory floors with only a few aircraft in production.
  • One of the good news stories about China and aviation is their adoption of pilot training and accountability practices, maintenance procedures, and safety protocols, bringing Chinese airlines’ safety records from one of the worst in the 80’s to now one of the best in the world.  However, the air traffic controllers are not accustomed to managing large amounts of traffic, given that most of the airspace is still military-controlled.
  • Chinese design and manufacture of aircraft is far behind the leaders of the world, and not likely to catch up for the next 20-30 years.  While the US and Europe have matured the aviation industry over the last 80-100 years to produce complex and highly reliable airframes, avionics, and engines, the Chinese do not have the technical background and high-quality manufacturing capacity to produce these on their own.
  • The environmental impacts of the way China does business is going to be a significant factor in the way the industry develops.
  • The politico-military situation is causing friction both domestically and internationally, and is truly a wild card–they could put the brakes on the whole thing if they got too paranoid.

The analysis:

This is an excellently written book, and it summarizes many of complex issues (harmonious chaos) surrounding aerospace industry in China. I found myself thinking of several articles my father-in-law has written about doing business in China: The Rules, Harmonious Chaos, and Chinese Icebergs.

The only “bad” part about this book is that it is probably sorely out of date even less than two years after publication (as evidenced by the progress in opening the airspace at Hongqiao). Hopefully Mr. Fallows will follow up with more articles in the Atlantic or a revised edition in a few year.

The verdict:

An excellent read not only for those interested in China and aerospace, but also those who are interested in Chinese business development in general.

The Real Future of Education?

Maybe breakthroughs in education won’t come in the form of MOOCs or technology, or smaller class sizes or charter schools.  Though one of the keys would appear to be the drastic improvement of elementary and secondary teaching quality, that is a tough hill to climb, with plenty of political obstacles and limited of short-term ROI. Instead, some German companies appear to be transplanting their apprenticeship model to certain places in the US: for the final two years of high school, the students take technical classes in addition to their graduation requirements and work for pay at the same time.

Courtesy Washington Post

This seems like a good idea on many, many levels.  No college debt.  Earning money in a career right away.  Not encouraging kids to go to college who don’t really have the desire or capability to be there.  Re-creating a manufacturing base in the US where American workers are valuable enough to keep companies here.

Recasting high school, German firms transplant apprentice model to U.S. | Washington Post

“Atmospheric satellites” poised to enter market

The number of potential beneficial uses for unmanned aircraft continues to grow.  At a fraction of the cost of a satellite in orbit, these aircraft can be used for months at a time to provide weather and atmospheric monitoring, aerial photography, and communications relay.

The technology is just starting to mature to the point where they can be really useful and reliable; I pray the FAA is considering this kind of aircraft as they continue to draft UAV rules.

Courtesy IEEE Spectrum

Introducing Solara, the Atmospheric Satellite | IEEE Spectrum

 

Did you know the Chinese have a robot on the moon?

It landed on December 14th and has been exploring ever since. The Yutu, or Jade Rabbit, is just the latest in what seems to be a slow, steady march forward in space technology and exploration for China. The Chinese have been launching their own version of GPS satellites, called BeiDou. The Chinese space station, Tiangong-1 has been orbiting for a couple years now, and the one-party government has the cash and the political will to make big bets on the future of Chinese technology. In one of the two articles below, it is claimed “By 2050, China should be the leading scientific nation in the world.” Wow.

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China: The Next Space Superpower

For the First Time in 40 Years, a Robot Is Wandering the Moon