Up until recently, Toronto snowmobile racer Shawn Watling used to create vehicle models with cardboard, string, and paper. Enter a professional engineering buddy who turned him onto SolidWorks software. Since then, Watling has tripled his work speed and won the Popular Science Invention Award for a device that could turn his sport on its head.

Watling designed a breakthrough snowmobile track powered by a rearward axle instead of the traditional one in the front of the sled. Third-party tests show that when compared with traditional designs, Watling’s Rear Axle Drive (RAD) technology delivers 30% more power to the ground than a traditional design, meaning faster acceleration; 10% increase in speed; 33% reduction in stopping distance; superior cruising and cornering; up to 72% increase in fuel economy.

The former provincial hockey star and millwright is now in talks with several household-name snowmobile makers considering acquiring the patent-pending technology.

Watling modeled his current prototype machine in SolidWorks – the whole sled – down to every screw and washer. He uses SolidWorks Simulation software for stress and motion analysis, and to cut excess weight from the design. He exchanges DXF files with machinists for water and laser cutting.

“I went through all the things a snow machine does and charted all the physics,” said Watling. “SolidWorks lets me try multiple scenarios using all types of geometry without having to make a physical prototype every time.  For example, I rattled off eight quick swing arm designs in a couple of days and used SolidWorks Simulation to measure the ground forces, which is a critical factor in this design. I designed my latest sled prototype in four months with SolidWorks, avoiding three or four physical prototypes and probably a year and a half of labor.”

By moving a snowmobile’s propulsion axle from the front to the back of the sled, RAD drives power directly to the ground. This is key to making the sled “carve like a snowboard, climb like a scared cat, launch like a dragster, crank in the corners, and stop like you snagged a fence,” according to Watling. The design further conserves energy by adding an extra 14-in. to the front track position and spending less effort pulling the track around the idler wheel.

Videos on Watling’s website show how RAD puts pressure on the skis when you need it — during acceleration — and lightens the pressure when you’re cruising to avoid the dangerous process of darting in and out of other riders’ grooves. Better weight distribution also minimizes sliding during braking and is crucial in fuel economy.  To further demonstrate superior performance, Watling is installing RAD on racing sleds that will generate 500 hp and attempt the Guiness world record for snow machine asphalt quarter-mile later this year. He’s also shooting for the vaunted Ice Oval record at Eagle River, Wisc. 

SolidWorks
www.solidworks.com