Backpack turns man into Energizer bunny

September 11, 2005

I saw this last week on Science Blog, but before I could get this message up, my father pointed out its presence on CNN.

We have all seen the bike lights powered by the motion of the tire, well if researches at the Marine Biological Laboratory are successful, backpackers may one day get the same kind of toys. It seems that “Suspended-load Backpack testers were able to generate up to 7.4 Watts–more than enough electricity to simultaneously power an MP3 player, a PDA, night vision goggles (or 3 LED headlamp), a handheld GPS, a CMOS image decoder, a GSM terminal in talk mode, and Bluetooth.”

Researchers describe a backpacker as an inverted pendulum saying that “The Suspended-load Backpack frame sits still on the wearer’s back, and the load is mounted on a load plate that is suspended from the frame by springs. The springs allow the load to slide up and down on bushings constrained to vertical rods, thus allowing the load to move with the same vertical motion as the hip, but lagging it by a fraction of a second, producing differential movement between the frame and load. The pogo-stick-like movement of the load generates mechanical energy that drives a rack-and-pinion device that powers a geared DC motor that acts as a generator mounted on the frame.”

That sounds great, but it can’t be lighter than my batteries.

Photo credit: Timothy K. Hamilton

No Comments »

No comments yet.

RSS feed for comments on this post. TrackBack URI

Leave a comment

You must be logged in to post a comment.