Trying to figure out the Segway...

[skimoose]

Originally Posted by KenWittlief

I think the feedback on the Segway is selectively loose - when you lean forward it compensates to keep you from falling over, but not completely, so the platform ends up moving forward - sorta like its perpetually falling

Good call, if I recall correctly from the book, that's how Dean got the project to finally work. He had fallen in the shower and the idea hit him of controlled falling.

Originally Posted by JBotAlan

I think it's a PID loop. As you lean, it adds the offset to a separate integral term that controls the speed. It seems simple, but for 5 grand, it seems that I'm missing something...or is it just overpriced?

JBot

It not just speed and direction, you're forgetting balance. You're not balancing the seg, it's balancing you.

You're also missing a lot of safety redundancy. There are (I think) eight gyros on board which are constantly polling and voting, similar to the way the systems work on the space shuttle where multiple redundant sensors provide data and then the results are voted on by the processors to weed out defective sensors or data.

And is it overpriced? I don't think so. If gas gets a little more expensive, say $4/gal., I'll be taking one to work, when I'm not mountain biking or roller-blading that is.

Just need one more mile of trail and I can commute about 75% of the way on the Quinnipiac River Linear Trail, and I saw the survey party out last week working on final designs!