91ÊÓƵ

A loud, punctuated and random thwacking noise greeted my fellow TriMet bus passengers and me over the past couple of icy days.

And while I can’t be positive, I’m fairly certain it was the sound of the , which is a technology the agency has been testing on about 65 buses this season.

The noise is a bit disturbing, albeit less so than it would be to watch my bus slide over the side of the Ross Island Bridge, but hey, at least it woke up the otherwise groggy 6:45 a.m. crowd of travelers.

The technology is less labor intensive for bus operators, because it’s basically a spider-like chain system that automatically drops down next to the tire to break up ice on the road beneath. No crews are required to install the thing or take it off if a driver wants to use it.

And since drivers don’t have to use it constantly, I suppose it’s a bit better for the roads than manually installed chains.

Having recently moved here from New Mexico, tire chains are a bit of a foreign concept to me. But I couldn’t help but be a bit fascinated with this technology and how it works.

The Oregonian popped up a video yesterday that shows the things in more detail. Check it out here:

The company also has its own video here: