Tuesday, September 10, 2013

Control Engineering?

My Master's degree

My MSE is from U. of Michigan, Ann Arbor. As I previously explained in a STEM post, I was there in a program sponsored by Bell Labs called "One Year On Campus". Within a maximum of 12 months, it was a requirement for my continued employment to complete a Master's of Science, Engineering degree. The Labs imposed a few additional requirements on the courses I was to take. I was to take an information theory and communications course (modulation techniques, etc., etc.), a digital logic course, and I'm not sure what all else. My main interest was in studying computer science, but the University had a requirement that X% of your courses had to be from within the department of your major. For broad studies of computing, that was a problem as the computing courses were spread throughout the University. The digital logic, machine architecture and assembly language courses were over in the Electrical Engineering department. The computer graphics courses were in the Industrial Engineering department. Operating systems, higher level languages and compilers were in the Computer Science department. Database courses were way over in the business school. So, the Engineering school created the "CICE - Computer, Information and Control Engineering" department to cross list all of the above courses. By majoring in CICE, I was able to take a broad variety of computing courses and still meet that X% within my major department requirement.

So much to do and only a year to do it. So, I admit that the edge of the CICE curriculum where I did not fit in many courses was control engineering. I had some exposure to it, but just enough to hum along if someone decided to sing about the subject. I couldn't even confidently promise to you a competent explanation of the topic if you asked me about it.

TED talk/demo of control engineering

So, I was excited today to find a most excellent TED talk demonstrating control engineering with a set of "Quad copters". The talk has some very impressive demonstrations of software control of the copters. I could wish for a more technical explanation then they offered. I'm not at all sure how many processors of what kind they used to track and control the copters. I'm pretty sure there's more real-time computation going on there then would comfortably fit into one processor, but that's just my gut feeling and not based on any real experience.

And so, for your entertainment and to convey to you what the heck "control engineering" is about, I share with you Raffaello D'Andrea: The astounding athletic power of quadcopters from June 2013. Run time of the video is about 16 minutes.

Want to know more?

I did some mild Google searching to try to find the source code for the control programs, which I assume are likely to be "open source". I didn't find exactly what I was looking for. But I did find some useful info. There's a Wikipedia article about Quadcopters and from there, there are plenty of links to additional information. I found this article about the lab where they test their stuff to be interesting. I was heartened to learn that they do have a safety net to catch the falling copters when the software is still under development. The article does give me the distinct impression that they've developed custom hardware to do the control algorithms fast enough. That is a potential major obstacle for a casual hobbyist who wants to play. If the Wikipedia article doesn't give you enough leads to follow there's an existing Pearltree specifically about quadcopters. I did find some open source (Arduino controller) quadcopter projects. e.g. this one and another one.

If you try your own Google searches, be careful about people in other fields of research with names similar to Raffaello D'Andrea. e.g. I found a biology PhD candidate at U. of Michigan named Rafael D'Andrea - Not the same guy. Oh, and I did find some Cornell U. work in the field of quadcopters too: Autonomous Quadcopter Docking System. Oh my, on page 11 of that report, the guy strapped his Android Smartphone to the quadcopter to add a camera to the configuration. That must have taken guts! (I wonder if he has the "Send me to Heaven" game on his Android phone? Not me!)

If you want to get into the math of control of a quadcopter, this looks like a reasonable place to start reading: Estimation and Control for an Open-Source Quadcopter. Or just sit back and enjoy the demo video that I pointed to in the previous section. Not everyone has to be a DIY engineer with amazing toys.