3D CAD praised for intuitive and logical design

Edited by the Engineeringtalk editorial team Nov 27, 2007

Move With Freedom designed its morphing handcycle entirely in SolidWorks 3D CAD software.

Imagine cycling 50 miles, stopping at a convenience store to refuel, and having no way to get inside.

This frustrating scenario, repeated ad nauseum, prompted a trio of avid handcyclists - whose machines were too big to get into the store and whose legs couldn't carry them - to create their own solution - the morphing handcycle, designed entirely in SolidWorks 3D CAD software.

In stretched-out lowrider position, it's a traditional handcycle - stable and aerodynamic, and ready to ride as far as any bicycle at roughly the same speed.

Morphed into high-rider position, it has a wheelchair's agility for navigating doorways and aisles.

It also puts the user at eye level with standing persons - optimal for picking items from store shelves.

Rory McCarthy, Bill Warner and Graham Butler designed the machine under the aegis of McCarthy and Warner's nonprofit Move With Freedom, based in Cambridge, Massachusetts.

"Any CAD software lets you design and assemble parts", says McCarthy, who has cycled the globe on a handcycle.

"SolidWorks software, however, made a big impact on our design by letting us experience the assembly in motion".

"Graham, our product designer and SolidWorks expert, was able to turn my high-level designs into detailed virtual prototypes".

"This was critical in conceiving and refining the four-bar linkage and the crankset/steering assembly, which needs to turn smoothly in both low- and high-riding positions".

"As a result, we've got a highly functioning physical prototype ready for user feedback".

The morphing handcycle involves no electronics.

To morph into high-riding position, the rider sets the brake and rolls the rear wheels forward, as with a wheelchair.

The 24-speed cycle employs twin mechanical gas shocks, specified for the rider's weight, that assist in the lift, enabling the user to switch to high-riding mode with single-hand force.

Other components are standard bike parts.

McCarthy is a long-time electrical engineering designer who embraced SolidWorks from the onset of the project two years ago.

"I'm a long-time AutoCAD software user, yet SolidWorks immediately proved to be a great tool and a more intuitive and logical way of designing".

"When it's time to build, most of the questions have already been answered".

"We took care of the trial and error on the screen".

The morphing handcycle embodies Move With Freedom's commitment to easy and natural mobility for all.

Rather than commercially protect it with patents, the company intends to donate the finished design to the public domain so that others can customise it for their own needs.

Move With Freedom's next project is a morphing wheelchair, which would make it easy for users to surmount a curb without risking a backward flip.

"We've seen many instances where SolidWorks improves business performance", says Rainer Gawlick, Vice President of Worldwide Marketing.

"It's inspiring in this case to see improved human performance and a direct positive impact on quality of life".

Move With Freedom's founding supporters include authorised SolidWorks reseller Capinc (Computer-Aided Products)".

"Through its "Engineers in Action" community involvement programme, Capinc has provided Move With Freedom additional grants for ongoing training, service and support.