Invention: The Alligator Tail

When a person with paraplegia is adjusting to life with a wheelchair, they will begin physical therapy by learning how to do a stationary wheelie. A wheelchair user performs this skill by lifting the front wheels of the wheelchair up a few inches with their weight resting on the larger back wheels. This allows them to navigate obstacles like uneven ground and curbs. A team of McCormick School of Engineering sophomores created the Alligator Tail, a device that is placed on the axle of a wheelchair and is used to prevent the user from falling while learning this technique. It allows users to practice wheelies with minimal assistance. The device’s designers, sophomores Elizabeth Petersen, Melanie Galantino, Justin Navidzadeh and Jacob Wat, teamed up during their first-year Design Thinking and Communication class and created the Alligator Tail with the help from their mentor, Amy Huckstep, a Shirley Ryan AbilityLab physical therapist.

Lindsey Yingling, a physical therapist and wheelchair seating expert for Shirley Ryan AbilityLab, demonstrates the Alligator Tail.

The Alligator Tail features include: 

1. A Cushioned Bed

A cushioned bed made from foam-covered plastic comes in direct contact with the chair after it reaches its tipping point. It is designed specifically to minimize any impact on the patient.

2. The Toothed Rail

The notched rail allows the therapist to adjust the angle of the bed, allowing patients of any shape, size or degree of comfort with the wheelchair the opportunity to practice a stationary wheelie as comfortably as possible.

3. Flexible Wheel

The 360-degree ball-and-socket wheel minimizes drag, ensuring that the device doesn’t inhibit the user’s lateral movement.

4. Wheelchair Attachment

To use the Alligator Tail, a physical therapist may hook the device around the wheelchair’s axle so that the aluminum-constructed frame extends behind the chair without affecting the chair’s balance.