Cheng-Shiu (Joshua) Chung, Xin Wang, Saleh AlQahtani
ABSTRACT
Most playground features are inaccessible to children with disabilities without supervision and/or assistance. To provide a device that is attractive and accessible to all children including those in wheelchairs, we designed a bowling slide which children with disabilities can remain seated in their wheelchairs while experiencing vestibular motion. Safety was analyzed by SolidWorks Motion and evaluated by a Certified Playground Safety Inspector. Feedback from parents, therapists and children with / without disabilities was obtained to assess system safety, feasibility, social interaction and fun factor.
KEYWORDS
wheelchair, safety, playground, slide, fun
BACKGROUND/SIGNIFICANCE/PROBLEM STATEMENT
In the United States, approximately 1.6 million Americans residing outside of institutions use wheelchairs1. An estimated number of 121,000 children under the age of 15 use wheelchairs according to statistics from the U.S. Census Bureau2.
Playgrounds are crucial social places that contribute to the cognitive, social, and emotional development of children. Unfortunately, most ground level elements in playgrounds are activity boards, which are inaccessible to children with disabilities due to the limited range of motion and upper extremity strength. In addition, children with disabilities may experience rejection and unequal treatment by their able bodied peers when playing together in current elements, leading to low self-esteem and low self-confidence.3
Slides are a common and exciting element in current playgrounds, and promote balance and functional coordination in children4. Based on the principles of universal design, our project of a bowling slide is accessible to all children, meanwhile improving their motor and manipulation skills, enhancing a healthy relationship among children with and without disabilities through social interaction, thus promoting both physical and mental health for all children.
There are a few US patents (US5505663 and US4865312) that cover technologies related to wheelchair accessible slides. Neither of these existing solutions allows an individual to remain in their wheelchair while on the slide. All solutions require children to transfer out of their wheelchairs and onto the slide, which requires assistance from one or two caregivers per child, and supervision is commonly needed in several stages of the slide process (getting onto the slide, bringing the empty wheelchair to the end of the slide, getting from the slide into the wheelchair). None of the technologies found in US slide patents are currently available on the market.
OBJECTIVE
The goal of this project is to develop a novel system that provides children with disabilities with a means for independent, fun and engaging play. This means that children can remain in their wheelchairs, and can experience safe but exciting vestibular motion (speed) and adventure.
METHODS/APPROACH
Inspection of Current Playgrounds
First, children with disabilities, parents and therapists at the Children’s Rehabilitation Institute in Pittsburgh were interviewed. Input was obtained from children on their most desirable experiences when on the playground. Most common issues and needs from the therapists and parents related to playgrounds were documented as well. Next a Quality Function Deployment matrix was developed (Table 1) and used as a design evaluation tool for the playground design.
After establishing user needs, technical requirements and design specifications for the playground solution, we brainstormed on ideas and solutions. We selected 3 ideas out of 9, which were evaluated on compliance with the QFD. To quantify compliance of each idea with each critical user need and to decide on the most promising design we used a Pugh Chart method.
Concept of Slides
The selected concept that scored highest on the Pugh Chart and met user needs sufficiently was the slide design, which consists of a sloped slide with side gutters to contain the wheelchair wheels (Figure 1). At the end of the slide large bowling pins are magnetically attached to the floor surface, which can be knocked over by the wheelchair or child on their way down the slide.
Define Essential Design Parameters
After the idea formed, the first thing is to retrieve the most important design parameters in the bowling slide. On the legislation side, this design has to meet all the regulations for playground design. On the fun and engaging part, this design has to be able to create enough speed for children with or without wheelchair. For the needs of public playground, material chosen has to be durable and less maintenance, as well as with low cost.
ADA requirements
First, our design should follow the required features by ADA: accessible route, ground surface, and turning space.
Playground regulations
We reviewed current playground regulations, ASTM, ICC/IBC, and NFPA, which list detailed design standards. It requires handle bars and gate on the higher surface of slide for able-bodied children from standing position to sitting position. It also describes the dimension of the slide for users with different ages.
Slide angle
To determine the slide angle, we measured the current slopes in playground, sidewalk slope angles around University of Pittsburgh campus as the safest angle. In addition, the stable angle range for manual wheelchair is around 20 to 34 degree and for power wheelchair is 19 to 37 degree. Therefore, we select the angle range between 10-18 for our slide angle. (Table 2)
Computational Model design and Dynamic Analysis
We used Solidworks to generate the sketch and computational modelsof slide, tunnels and bowling pins, and carried on dynamic motion test (as showed in the movie.)
Sketch of computation model of slide
The revised slide is comprised of two, 1-meter, sloped sections (Figure 2) that are connected with a middle curved (90 deg) section (Figure 3 and 6). The first section of the slope is 15degrees (Figure 4), the second section is 18 degrees (Figure 5). The sloped sections have two parallel gutters that guide a wheelchair during its travel down the slope. At the end of the slide there is a slight rise-up of the slide surface (Figure 7) to reduce wheelchair rolling/child sliding speed before reaching a structure with energy absorbing bowling pins.
Model of bowling pins
This revised bowling slide design has safety energy absorbing pins attached to a side structure (Figure 9). Children in wheelchairs, especially manual wheelchairs, have lower friction so that they may generate a higher speed on the second portion of the slide. Bowling pins at the end of the slide are made of soft energy absorbing material and rotate to the sides (Figure 10) when bumped into by children coming down the slide. These pins may help reduce (manual) wheelchair speed (Figure 11) but more importantly, the bowling pins promote the physical experience of children bumping into something. The pins rotate back in place using a torsion spring mechanism.
Model of tunnels and turning part
A tunnel placed on both sloped sections will not only protect children from falling, but also make the bowling slide experience more mysterious. When wheelchair-seated children approach the middle section of the slide, the child will have to slow down their wheelchair speed. An energy absorbing cushion is mounted to the tunnel section to help them slow down and turn safely (Figure 11). There are audio and visual stimulation buttons on the tunnel walls (Figure 12), which will produce scary sounds, animal sounds, and colorful lights.
MATERIALS AND COST
The slide will consist of 4 plastic tunnel sections (~$200) and 2 concrete slope sections (~$950). To install this slide the customer has to dig a section for the lower end of the slide and locally waterproof the ground. The concrete slabs are placed down and made even with the surrounding landscape. The tunnel sections are anchored to each other and onto the concrete sections. The bowling pin structure is made of 3 steel tubing sections ($100) that are simply bolted to the ground. The bowling pins are attached to the steel tubing with torsion springs ($5 per each) and made of a foam-type material ($2 per foot square).
EVALUATION
The design concept was evaluated for safety by a certified playground safety inspector from the National Recreation and Park Association. This specialist has expertise in forensic biomechanics and analyzes human movement, and playground associated injuries. His main concern with the original slide design was the risk of injury when wheelchair-seated kids slide down from 2 meters high at once. Hazards may include sideways or rearward tipping of the wheelchair, or falls from a wheelchair if no seat belt is used and/or the wheelchair is off-balance due to an oxygen tank on the back of the wheelchair. In addition, a child may use the wheelchair brakes to reduce speed while rolling down the slide. Wheelchair brakes are not designed for this purpose and may fail putting the child at risk of injury. The bowling pins as originally designed to attach to the floor surface might cause a wheelchair to tip if the pins get stuck in or under the wheels. The expert has suggested follow the design guidelines in the ASTM F1487-07 playground regulation to further improve upon the safety of our design. As a result of this safety expert’s input we addressed the safety issues in the following ways. We divided the slide into two shorter sloped sections, where the first sloped section is angled at 12* and the second sloped section is angled at 18*. In addition, we have added handle bars for able-bodied kids to assist them in positioning themselves seated on the slide. At the end of the slide, we changed the bowling pins position and mounted them on a side structure.
In addition, the design concept was evaluated by the staff at the Children’s Institute in Pittsburgh, including the end users (the children) and the therapists. They were very interested and exited to experience this kind of playground equipment. The most interested parts they have expressed are experiencing the sliding down throughout the tunnels to as well as hitting the pins at the end of the slide. The therapists expressed their willing about the safety and the design itself.
CONCLUSION/DISCUSSION
In summary, the bowling slide met all of the project goals, design specifications and exhibiting the great marketing potential because of low cost, low maintenance, building easily and universal design. The designed slide acts as a means to get from a higher point to a lower point on a playground and allows children with and without disabilities to slide and play a bowling game. The slide stimulates interaction among peers with and without disabilities. Children will be exposed to an exciting adventure while passing through the slide tunnels and interacting with sound features on the slide and with movable bowling pins at the end the slide. This design not only provides a novel slide and bowling game for all children, but also improves the physical interaction, social interaction, and psychological development of children with and without disabilities. And in the future, we will take more safety test by computational model and/or prototype model, as well as durability test of product in the future.
REFERENCES
1.Kaye, H.S., Kang, T., and LaPlante, M.P. 2000. Mobility Device Use in the United States. Disability Statistics Report 14. Washington, DC: U.S. Department of Education, National Institute on Disability and Rehabilitation Research.
2. US Census Bureau: AMERICANS WITH DISABILITIES: 2002
3. Sharika Bhattacharya, Holly Cummings, Jordan Gilmore, Amanda Karr, Clint Lee, Jamie Olson, Jonathan Roberts, Dora Syin, Paula Yellon, Nathan Yokel. Universal Playgrounds:
Integrating All Children Through Play. Thesis submitted in partial fulfillment of the requirements of the Gemstone Program, University of Maryland, 2003.
4. Research Paper: The Benefits of Playgrounds for Children Aged 0-5. Prepared for the Shasta Children and Families First Commission by Duerr Evaluation Resources.
ACKNOWLEDGEMENTS
School of Health and Rehabilitation , University of Pittsburgh
Human Engineering Research Laboratories, University of Pittsburgh
Children’s Institute in Pittsburgh
Al Vangura Jr., MS, CPSI (Biomechanics, Bioengineering and Product Development Consultant )
(First author: Cheng-Shiu (Joshua) Chung, joshua.grace@gmail.com, )