Wheelchair Backpack Storage Mechanism

Background

A lack of mobility is a struggle that many people in wheelchairs deal with. In the United States alone, 5.4 million people are paraplegics, but not all of them require the assistance of a wheelchair.
There are an estimated 3.3 million wheelchair users in the U.S. with this number increasing by approximately 2 million new users each year.
The use of a traditional backpack is an everyday task that most people take for granted but people in wheelchairs struggle with.
Wheelchair users are forced to hang backpacks on the backs of their chairs and then blindly reach behind to search for what they need, which is not only extremely inconvenient but can also lead to pulled muscles and overexertion of the user’s upper extremities, potentially leading to further damage in the future.
Hanging a backpack on the seat back of a wheelchair with no modifications also shifts the wheelchair’s center of gravity back, increasing the likelihood that the wheelchair will tip backwards.

To help these users, a mechanism should be designed that can attach to and store a backpack behind a wheelchair and bring the backpack around to a convenient location to allow the user to access the backpack without strain.
Products currently on the market are either not fully mechanized or still require a certain degree of mobility from the user, making the day-to-day use of such products challenging for those users with severe impairments to their range of movement.

A four-bar linkage was synthesized using three-position synthesis and other principles of machine analysis and design.
The linkage starts underneath the wheelchair while the backpack hangs from an extended hook behind the wheelchair.
As the mechanism is activated, the linkage swings upwards and brings the backpack over the user’s head until it reaches its final position, where the user can access the backpack.
SOLIDWORKS was used to create a full assembly model of the wheelchair and linkage.

Andy Du, Vanderbilt School of Engineering, Mechanical Engineering

Lauren Chang, Vanderbilt School of Engineering, Mechanical Engineering

Lauren Grohowski, Vanderbilt School of Engineering, Mechanical Engineering