MaplePrimes - Maplesoft Blog - Posts by Dr. Derek Wright

An analytical model of mornings in the Wright household

Derek Wright — Mon, 01 Feb 2010 21:21:36 Z

I’m not a morning person. Well, that’s not entirely true: I am not particularly a morning person, but relative to my wife, Amy, I seem awfully crusty and curmudgeonly for about an hour after waking up. She, on the other hand, is definitely of the “up and at ‘em” variety. As such, I would like to credit coffee with contributing significantly to our happy marriage these last five years.

With so many data points I can now reliably say that it is in everyone’s best interest for me to wake up first, or for us to wake up at the same time. If Amy gets up first, by the time I wake up she is reciting lists of “things I’d like to do today” as I groggily attempt to get that first double espresso to my lips. This is where something interesting happens: If I don’t perk up, Amy gets extra happy in an attempt to cheer me up (just give me time to wake up!). This implicitly suggests that she is using her mood as a forcing function to my mood. If I still don’t perk up, then things turn ugly as I am clearly being insensitive to her generous efforts to cheer me up, and her mood drops. Conversely, if I do perk up, whether from the coffee or her cheerfulness, all is well.

Limits only serve to limit, so change the game

Dr. Derek Wright — Fri, 18 Dec 2009 15:29:14 Z

Undergraduate engineering and science consists of learning various rules and laws that govern the domains of interest. For me, it was Maxwell’s Equations for electromagnetics, the Navier-Stokes equation for acoustics, the Rayleigh criterion for imaging, the speed of light, et cetera ad nauseam. What is frequently missed or neglected in teaching and in practice is how these rules and limits are simply the boundaries of the game – endpoints on a spectrum of possibilities. That’s why a recent headline caught my attention: “Computers to Get Faster Only for 75 More Years". I find it hard to believe that humans a thousand years from now will be commemorating 2084 as “The Year Computers Stopped Getting Faster”. After reading the research paper from which this headline arose, I was reminded that innovative science doesn’t set limits, it uses them as tools. Since this is precisely what we do in Applications Engineering at Maplesoft, I thought it would be worth looking into a little further.

A battery isn’t just a voltage source

Dr. Derek Wright — Wed, 28 Oct 2009 19:17:13 Z

A leading motorcycle manufacturer has been using MapleSim to model their powertrain, and now they want to include a realistic battery model. This would let them choose batteries and accessories (like starters and alternators) that they can simulate under a variety of operating conditions, along with their powertrain model. The company turned to Maplesoft to help with this modeling exercise and I was put on the task. My background is in circuits so I thought this would be a straightforward project. In my mind batteries were just constant voltage sources that eventually ran out of charge. I was able to find several recent research papers on battery models, and I realized their behavior was much more complicated than a simple voltage source.