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Project 5: Supportive wheelchair

Abstract

Our goal is to design a new wheelchair for an eight-year-old boy with cerebral palsy.  The family and teacher are concerned that the current wheelchair is allowing the child to slouch and shift his weight in his seat, causing problems such as a need for hip replacement, feet not staying in the footrest, and restraints causing skin irritation and discomfort. The headrest is fixed and rubs on the child’s head causing a bald spot, and the current removable activity tray is difficult to remove and attach.

Hamza Ansari, Helaena Pfeiffer, Hailie Pippin, Ayla Render, Kaleb Sanford, Jane Vassar

Problem Statement

Cerebral palsy can increase muscle tone and lead to spasms in the limbs. The child has generally increased tone in upper and lower extremities and fair head and trunk control. He is dependent in transfers and mobility and is incontinent. He also presents with a flexor synergy pattern and often struggles with independence. Due to this, our wheelchair will need special support to the torso, hips, and legs. For this project our team will be designing and developing a new wheelchair that will add support for muscle tone, minimize skin integrity issues, increase independence, and have a personal flair.

To help support muscle tone, the chair will need to prevent the child from being able to slide out of the proper 90 degree sitting position or unevenly distribute his weight. This positioning will be even more important after the child’s hip surgery in the coming year. Improper positioning can cause the hip to dislocate after surgery. To minimize skin integrity issues, a comfortable and easy to clean material will be needed and the seat restraints may need to be redesigned to reduce friction. We also have a goal to better facilitate his independence. We want to make it easier for him to participate in class and work on skills such as learning to feed himself.

Design Specifications

  • Adjustable seat that tilts while maintaining proper 90-degree hip position
  • Adjustable/removable head rest
  • Easily removable activity tray with smooth top
  • Chest support paddle cushions
  • Comfortable support straps
  • Adjustable foot tray
  • Easy to clean material
  • Able to grow into
  • Blue

Background Research

Our family’s child has spastic cerebral palsy. We did some research on the symptoms and difficulties that come along with his condition so we could better understand the type of adjustments he may need for his wheelchair to make him more comfortable. We also talked to an Occupational Therapist (OT) who specializes in fitting children and their symptoms to wheelchairs and aftermarket products. We discussed the needs of the child and were recommended various strategies to think about when designing and building our own. She also suggested we talk to an Assistive Technology Practitioner (ATP) in our area once we have concept designs.

We also looked into wheelchairs and products currently on the market and determined that the wheelchair that meets all the current needs except the activity tray is the Zippy Tilt-in-Space wheelchair technology.

Concept Design 1

Adjustable Tilt Wheelchair with Tray

  • buy a new wheelchair that already fixes some of the main issues. The Zippie Iris is a top of the line wheelchair that costs $3147 and has the following features:
    • 40 – 55 degrees of tilt
    • Folding cross brace that allows the chair to be folded for easy transportation.
    • Growth capabilities, ability to adjust to continue to bring support as the child ages. the company also provides a free growth kit so the chair can be adjusted.
  • Design and attach activity tray

Pros:

  • Able to give a wheelchair that meets all its needs without us having to design a fix for each problem.
  • Able to focus on our designs to make sure all possible issues with the wheelchair are fixed.

Cons:

  • Very expensive, this concept will have the largest budget.
  • We wouldn’t be doing much problem solving ourselves unless there were additional problems listed.

 

Concept Design 2

Reconstructed Adjustable Tilt Wheelchair from Static Model

  • Design and modify full adjustable tilt with solid backrest shell, side supports, and solid seat cushion
  • Lap restrains parallel to seat
  • Adjustable removable headrest
  • Removable tray
  • Upholster with Naugahyde

Pros:

  • Cheap
  • Adjustable tilt and headrest

Cons:

  • More work to fabricate
  • Potentially less durable
  • Less portable

Concept Design 3

Fixed Tilt Wheelchair from Static Model

  • Taller front caster wheels to create a fixed seat tilt
  • Removable back with side supports and removable seat for easier transfer
  • Removable headrest
  • Parallel lap restraint
  • Removable tray
  • Upholster with Naugahyde

Pros:

  • Easier to fabricate
  • Easier to store and transport
  • Maintains most features of original wheelchair
  • Can be further adapted

Cons:

  • No adjustable seat tilt or headrest
  • Weight through hips and lower back for all the time in chair

Selected Concept Design

Concept one is the best based off the decision matrix, however it is outside of our expected budget and is therefore not feasible. Our next best option is concept 3 with the second highest score on the decision matrix. We plan to add the adjustable head rest from concept 2 to the design for concept 3 to try to meet more of the goals requested by the family. Concept 3 is the best because Concept 2 is much more difficult to fabricate in our limited time this semester and the amount of failure points that would be introduced is too concerning to choose for a project that is only one semester long.

Decision Matrix

Semester

2024 Spring