Tuesday, December 30, 2008

Still around after the storm

It's been a busy month, personally and professionally.  Aside from new hires and a reorg at work, on December 11th there was a huge ice storm in the New England area that knocked out my electricity for ten days.   Luckily I got it back before Christmas - some people weren't as lucky.

Anyway, I have several more posts that I'll be getting up this winter.  As I've said before, I usually flag emails/articles/etc. when I find something interesting to say.  I'm about due for another clearing of the in-basket.

Shot of the woods near my house the day after the storm.

Friday, December 5, 2008

The power of repeated testing

I know I've talked before about statistics in relation to test engineering (here or here for example).  One thing I haven't really discussed is Gage R&R testing, but something personally happened to me this week that reminded me how useful that testing tool can be.

Where I live is close to the bottom of a hill within a subdivision.  I have found, through repeated testing, that if I a) shift my Toyota Prius into neutral at a specific speed once I turn into the subdivision and b) follow the same path, then I can overcome the two small hills and coast all the way down to the end of my driveway.  It's kind of a geeky thing to know, but I'm an engineer with a cool car built to do stuff like that.

Last week I got new tires.  A day later I took the normal coast route but the car felt different - a little slower while coasting.  I had shifted into neutral within a couple mph, the roads were not slippery so I didn't need to brake excessively for the curves, but it was definitely slower.  So I called the shop &, as I suspected, they need to be balanced better.

This is a perfect example of why you should run a Gage R&R on your test system every once in a while.    Like my regular "coast to the house" test, a regular test against a known standard will show you if there is something a little "off balance" with your system.