Developers: Sameer Pandhare, Emily Shannon, Alice Silberstein
Advisors: Edie Kahn, OTR, Whitney Mallallieu, PT, Kathy Davis, SLP, Josie Ghigliotty, VS, Pam Morgan, Teacher
Supervising Professor: Kevin Caves
Abstract
Abstract
For children with disabilities, teaching and therapy sessions require flexibility in presenting materials, the ability to switch between tasks easily, and room to store many supplies. Acknowledging this difficulty for our client, our goal was to develop an adjustable worktable to facilitate her schooling and therapy. We incorporated adjustable height, a tilting surface, and an expandable tray, also adding a rubber protective lip around the edge and interchangeable surfaces for presenting materials more easily. This device accomplished the goal of improving our client’s teaching and therapy sessions, and will continue to do so as she grows.
Introduction and Background
Our client Jenny is a 9-year-old girl with cerebral palsy, Down syndrome, and cortical visual impairment. Cerebral palsy is a neurological disorder that interferes with motor coordination; it reduces control over muscle tone, producing involuntary stiffness or weakness [1]. Due to these deficits, Jenny cannot hold herself up or control her arm movements. Down syndrome also contributes to inconsistent muscle tone, as well as cognitive delays [2]. She often requires a significant amount of time to react when asked to make a choice. Additionally, her visual impairment disrupts her ability to process images, so that objects must be presented at close range [3].
Jenny receives in-home schooling and therapy, either from her manual wheelchair or on a therapy mat. While in the chair, her teacher or therapist sits across from her and presents educational materials or communication tools from the other side of a removable tray table, which attaches to the wheelchair arms. These sessions require a lot of materials, including a light box, an iPad, and communication switches. However, the tray is too small to fit all the materials used during these sessions, which causes some items to fall off easily.
The tray attached to Jenny’s chair is removable and easily stowed, but is limited in size and she often knocks materials over the shallow sides. Other trays and work tables available through Tumble Forms, an adaptive device company, incorporate adjustable height and angle of tilt to provide children with space for activities [4]. Though the family has a Tumble Forms table from when Jenny was younger, it is now too narrow, lacks enough space for her materials, and cannot reach the height of her wheelchair.
Project Goals
The goal of our project is to design a device that improves Jenny’s access to her materials and provides her teacher and therapists with more space and better organization. This device will be easy to set up and adjust, stable enough to hold her materials and withstand kicking, and will conveniently fit in her home. Our design will incorporate the adjustable features of the Tumble Forms table, along with the convenient storage of the removable tray. It will also help the teacher and therapists store materials and keep them in place during use.
Design and Development
Our device is a modular table space that incorporates three main components: a sliding tray, a tilting surface, and adjustable table legs. Jenny will sit on the side of the table that is curved inward, and her teacher or therapist will sit on the opposite side. Figure 1 shows a top-down view of the table, with Jenny’s side at the bottom of the image, and the teacher’s side at the top.
The table structure is 46” long and 24” wide, and is divided into two functional pieces: one side features a sliding tray and the other incorporates a tilting surface. The relative dimensions of these two pieces are shown in Figure 1. The teacher can operate the sliding drawer to access more space for materials, and manipulate the tilting surface to angle materials towards Jenny. Folding, height-adjustable table legs are attached to the bottom surface, and can reach heights between 25” and 38”.
A: Sliding Tray
To provide more surface area for the teacher to place materials during sessions with Jenny, without requiring additional storage space, a sliding tray is featured on the teacher’s side of the table (Figure 2).
The tray is housed within an outer structure (“drawer box”), which is made from ½” hardwood plywood, and attaches by drawer slides. The tray, made from the same material, is 10” wide and extends and extends approximately 18” beyond the table edge when pulled out. This structure is also stained and coated with polyurethane.
B: Tilting Surface
A tilting surface is integrated into the table to create more options for presenting materials. The angle of tilt can be adjusted on the teacher’s side, so that the surface angles towards Jenny. This configuration accommodates Jenny’s visual impairment, as it allows materials to be presented at close range. Additionally, Dycem and Velcro sheets can be clipped onto the sides of the surface, to help support the materials during use.
This portion of the table consists of a wooden panel attached by a piano hinge, and a set of pieces that help support the surface at various angles (“tilting apparatus”) – these components can be seen in Figure 3. The top sheet is cut from ½” hardwood plywood, stained and coated with polyurethane. It is attached to the table by a piano hinge covered with plastic. On the underside of this sheet, the tilting apparatus is allowed to rotate about the horizontal axis via a wood screw inside a metal spacer. The tilting apparatus features a ¼” steel rod that sits inside grooves on the lower surface.
The lower surface is a flat sheet with windows cut out to accommodate the tilting apparatus. On the teacher’s side of the table, this piece has six grooves cut into the surface using a router. The metal rod sits in the grooves when the surface is set to different angles. An additional block of wood is attached to the base of this section to help secure it to the other half of the table.
C: Table Legs
To reach a range of heights, adjustable table legs are incorporated into the device, as shown in Figure 4. The adjustability allows the teacher and therapists more flexibility when presenting materials, as they can raise and lower the table surface with a simple push button mechanism. In this way, the device will accommodate multiple wheelchairs and can be used as Jenny grows.
The legs are H-type folding legs made from 18-gauge steel, purchased from KE Hardware (SKU: HS20-ADJ) [5]. They are height-adjustable between 25” and 38”, and the height of each leg can be changed by holding down the push button and sliding the inner shaft to the desired height. Each leg has four brackets fastened to the bottom of the table and held in place by wingnuts. The legs are offset by 2” to allow overlap when they are folded up.
Evaluation
This product was designed to provide a better method to present educational materials to Jenny and enable her teacher/therapist to interact with her more effectively. In order to accommodate the client’s limited mobility and dexterity, the device provides a stable table surface that keeps objects secured in place and has a lip around the table to prevent objects from falling if hit. The device also reaches multiple heights, which helps accommodate Jenny’s growing body. In addition to providing ample space for Jenny’s sessions, the device is compact and portable and can be assembled with ease.
The product was evaluated against the design specifications and performance criteria for various specific features. The testing phase consisted of verification tests by the designers in a lab setting and validation testing with our client using the device directly. To test usability, the device was delivered to our client for two days. During this time frame, the product was used in the client’s sessions with her teacher and vision therapist and a survey using a 5-point Likert scale was created and distributed for feedback. This survey assessed design specifications, operation of specific features (the tilting mechanism, pull-out tray, lip, and table legs) and safety criteria. A section on the survey also asked for feedback on the sturdiness and stability of the table and interaction as a whole. Results from this survey demonstrated satisfaction with the device’s variety of features and the client’s teacher and therapist reported that their sessions with Jenny were much improved because of the device.
Discussion & Conclusion
Each feature of our device ties back to the needs and priorities expressed by Jenny’s support team, coming together into a final product that provides a range of functions within the specified constraints. During testing, the feedback we received demonstrated that the device made sessions with Jenny much easier and provided her teacher and therapists easy access to materials. Our table has not only improved sessions for Jenny, but also paved the path for new and more engaging interactions that can help her make strides in non-verbal communication with those who work with her.
References
[1] “Cerebral Palsy: Hope Through Research.” National Institute of Neurological Disorders and Stroke. 2013. Retrieved Sept. 17, 2017, from https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Hope-Through-Research/Cerebral-Palsy-Hope-Through-Research.
[2] “What is Down Syndrome.” National Down Syndrome Society. 2012. Retrieved Sept. 17, 2017, from http://www.ndss.org/Down-Syndrome/What-Is-Down-Syndrome/.
[3] “Cortical Visual Impairment.” American Association for Pediatric Ophthalmology and Strabismus. 2015. Retrieved Sept. 17, 2017, from https://www.aapos.org/terms/conditions/40.
[4] “Tumble Forms Trays, Work Tables.” Adaptive Mall. 2017. Retrieved Sept. 17, 2017, from http://www.adaptivemall.com/traywortab.html.
[5] “20” Wide Adjustable H-Type Table Legs.” TableLegsOnline – A Division of KE Hardware. 2017. Retrieved Oct. 23, 2017, from https://www.tablelegsonline.com/adjustable-h-type.html.
Acknowledgements
We would like to thank the following individuals for their help on this project: Kevin Caves, Paul Thompson, Matt Brown, Steve Earp, Greg Bumpass, Edie Kahn, and the rest of our client’s family members, teachers, and therapy team. We would also like to acknowledge the National Science Foundation grant # CBET 3310005.
First Author Address
Emily Shannon
2700 Briarcliff Pl.
Charlotte, NC 28207