QL+ Students from Colorado School of Mines were tasked with the Challenge of designing a wheelchair to traverse the beach for QL+ Challenger and Navy Veteran, Nathan DeWalt. While serving in the Navy, Nathan was injured on a motorcycle while traveling home from a training exercise. Nathan lives in Florida and enjoys spending time with his wife daughters, traversing the beach with his family.

 

The Challenge is to design modifications to our Nathan’s existing wheelchair or an attachment that is easily mounted onto his current wheelchair. This design can be either manual or motorized but must allow the user to travel on the beach with minimal extra effort. The final design needs to be safe, waterproof, and allow Nathan transverse the beach with continuous momentum. 

 

The primary objective of this project is to create or modify a wheelchair for beach use allowing continuous momentum and ease of movement through sand. This device should meet all requirements and restrictions. The wheelchair must not use current, big beach wheels.  The device must be able to withstand shallow water.  The device must be able to transition from regular use to beach use easily.  The device must be lightweight but also stable and durable.  Nathan must be able to attach it to the wheelchair.  The device must be safe. It must be cost-effective.  It can’t be too noticeable, according to client’s standards.  Nathan must be able to operate it without assistance from others.  Lastly, the device must not make use of tracks.

 

The team created CAD models of all the different components along with a list of pros and cons.  They decided to present several different components that could work together and could be added to the wheelchair. These components could also be used as standalone devices. This way the Nathan could essentially build the wheelchair he saw best fit his purpose.  They presented a ratchet design, a front wheel attachment, a back-wheel tread design, and power assist rear wheel system. 

 

After a concept presentation and preliminary design review, the team decided to move forward with three of the components: the rear wheel tread, front wheel ski, and the ratchet system. Eventually, the ski design was determined to be ineffective, and the team decided to move in a different direction. 

 

Once they had the components determined, they started refining the designs of each to fit on Nathan’s wheelchair.  After the team acquired a wheelchair from a seller in Denver, the ratchet system was designed to stay attached to the axle. The treads were printed using a 3D printer. The team created the bowl design for the front wheels from using parts manufactured on campus and using components from a local hardware store.   

 

We are grateful for their hard work and their dedication to improving Nathan’s quality of life!