Child Passenger Safety Seat Ross Gerber, Aman Ghotra, Erik Bieging, Miguel Benson & Karim Mahamud Client: Tom Brazelton, MD, MPH Dept. of Pediatrics – UW Hospital & Clinics Advisor: Mitch Tyler Dept. of Biomedical Engineering

Outline Background/Motivation Problem Statement  Design Constraints Design Solution: Universal Child Seat  Overall Function  Components: Recline Lock, Sliding Strap Anchor, Back Rest Track and Leg Support Future Work

Background  There are an estimated 5000 ambulance crashes annually [1].  Dr. Levick’s study on patients under age 14 transported in ambulances: 37 % were unrestrained or sat in a person’s lap. >60% were on the gurney, but improperly strapped. Recommendation: Place children in child seat and on stretcher [2].

Background/Motivation Problems with Current Method:  Seat does not recline  Seat is bulky and non- collapsible

Problem Statement Develop a safe method of transporting children (6-30 kg) in ambulances that allows the Emergency Medical Technicians (EMT) to recline the child from the sitting position to the lying position when the child seat is strapped on a stretcher.

Design Constraints The Child Seat: 1. Must be compatible with current stretchers; 2. Must secure a child (up to 10 year old) -Mass: 6-30 kg -Shoulder width: cm, -Hip to shoulder height: cm [3]; 3. Must not restrict the EMT’s ability to care for the child; 4. Must be cost-efficient and user-friendly; 5. Must be collapsible; 6. Must recline from degrees; 7. Must be easily sterilized.

Design: Animation

Components of Child Seat Recline Lock Sliding Strap Anchor Back Rest Track Leg Support

Recline Lock Mechanism Helps recline the seat 2 quarter discs placed above each other One disk connected to seat and other to backrest One disc has a rail/track and other has a roller that slides along the track The sliding disc has holes at the bottom that allows a pin to hold the seat from 120 to 180 degrees

Recline Lock Mechanism Advantages:  Easy to recline because not spring loaded  Adjust to many positions  Forces acting either on the seat or backrest  Stable Disadvantages:  Lock mechanism can only be adjusted from one side

Sliding Strap Anchor Used to adjust Straps Latch secures slide in place “Water cooler” design allows for free hands Deformable rubber disk for latch support

Sliding Strap Anchor (cont.) Dual Pins provide better support Latch above shoulder position Pin slot much narrower than strap hole Sliding strap anchor allows for any size

Back Rest Track Compatible with stretcher straps Three I-Beam tracks on the back rest slide into groves in anchored back Anchored back is strapped firmly to stretcher Allows back rest to move relative to the stretcher while reclining

Leg Support Slides out from beneath base of seat Supported by fitting tightly into slot in base of seat Optional Vertical Support:  Advantage: support can handle big forces  Disadvantages: Adds complexity; May not be stable on a soft stretcher

Future Work: Find and Purchase components Modify existing Child Seat Minimize complexity and bulkiness of seat Crash Testing

Questions?

References [1] Safe Ride News. [2] Detroit News. [3] Physical Characteristics of Children.