Machine Design

On a quadcycle built for four

Steven Morgenstern's first human-powered vehicle (HPV) now appears in bicycle shows and kinetic-sculpture events across the country.

But Morgernstern, chief engineer at R. Mathews Optical Works Inc., Poulsbo, Wash., has plans for a second-generation model. He uses VX CAD/CAM on the job and in his avocation, which is designing HPVs. The new bike seats four and has articulated steering, a 21-speed drivetrain, and hydraulic disc brakes. The structure is all aluminum, and each wheel is made from two spun-aluminum saucers mated to a single rim. The vehicle was designed to operate in mud, sand, and water.


Steven Morgenstern's first-generation human-powered vehicle.

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