TEAM MEMBERS Miguel Benson Erik Bieging Ross Gerber Aman Ghotra Abdikarim Mahamud Department of Biomedical Engineering TEAM ADVSIOR Mitch Tyler MS PE Department of Biomedical Engineering TEAM CLIENT Tom Brazelton MD MPH Department of Pediatrics UW Madison Hospital and Clinics Abstract We propose a physical prototype of a gurney compatiblechild seat for transporting children in ambulances Current seats do not recline Emergency Medical Technicians EMTs must unstrap the child out of seat and remove the seat off the gurney to lay the child flat on the gurney for specific medical treatments However this procedure takes up valuable time 3 minutes and protracts the time it takes to reach the hospital As a result our prototype reclines and eliminates the need to remove the seat off the gurney to lay the child flat on the gurney Also our prototype supports children 1 10 years old of various anatomical features unlike current ambulatory child seats Initial testing of four subjects 1 10 year old have given promising results but more testing needs to be done to assess prototype s mechanical and safety constraints Also we need to seek lighter yet robust material to fabricate future design of the child seat Background An estimated 5000 ambulance crashes annually 1 Safest to transport children sitting up 30 kg in child seat attached to gurney in an ambulance 2 For specific medical conditions EMTs must unstrap child out of seat and remove the seat off the gurney to lay the child flat on the gurney 3 Background Motivation Problems with Current Design Seat does not recline Time consuming 3 mins because must remove the seat off gurney to lay child flat Seat is bulky Do not always carry seats in ambulances Children more prone to injury Problem Statement Develop a safe and compact child seat for transporting children 6 30 kg in ambulances that allows Emergency Medical Technicians EMTs to recline the child in the seat from the sitting position to the lying position when strapped onto 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 12 9 30 8 cm Hip to shoulder height 20 44 cm 4 3 Must not restrict EMT s ability to care for the child 4 Must be cost efficient and user friendly 5 Must be collapsible 6 Must recline from 120 180 degrees 7 Must be easily sterilized Overview of the Design We have incorporated four unique features that make the child seat more conducive to ambulance transportation Recline Lock Sliding Strap Back Rest Leg Support Overview of Design Concept Recline Lock Mechanism Function Reclines the seat Mechanism Similar to a hinge joint 2 plates joined at center rotate freely about the joint 1 plate permanently fixed to the seat while the other is attached to the back rest on a rail mechanism Lock in position with pin Materials Wood and Screws Figure B Prototype Model Figure A Design Concept Figure C Prototype Model Sliding Strap Anchor Function Used to adjust straps Mechanism Latch secures slide in place Over center design allows for free hands Deformable rubber disk for latch support Materials Wood Screws Nails Plastic Figure D Design Concept Figure E Prototype Design Figure F Prototype Design Back Rest Track Function Anchors back of seat to stretcher Allows seat and stretcher to be reclined simultaneously Mechanism 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 Materials Wood PVC piping screws Figure G Design Concept Figure H Prototype Design Leg Support Function Elevates patient s legs if necessary Mechanism Slides out from beneath base of seat Supported metal rails fit into base of seat Materials Wood railing Figure I Design Concept Figure J Prototype Design Materials and Cost Materials Cost Plywood Wood Foam Straps Donated by our client Hinges Hooks Nails Screws Nuts and Bolts 10 00 Sliding Bars 5 00 Fabric Glue 5 00 Total Cost 20 00 Subject Testing Tested our prototype on four subjects from the following age groups 1 year old 4 year old 6 year old 10 year old Figure K 1 year old subject in upright position Figure L 1 year old subject in laying position Testing cont Figure M 6 year old subject in upright position Figure N 6 year old subject in laying position Subject Testing Results All 4 subjects fit well in seat Easy to adjust seat with subjects in it Difficult for one operator to adjust seat and straps simultaneously Future Considerations PROBLEMS POSSIBLE SOLUTIONS 1 Heavy Design 1 Use light yet robust material i e plastic seat with metal frame 2 Strap mechanism difficult to slide 2 Add rails to keep mechanism in proper orientation 3 Have not done crash testing 3 Use Burlington Testing Facility next semester 4 Lock mechanism only has 2 options 4 Add more locking positions 5 Only a 3 point harness is used 5 Add straps to complete 5 point harness 6 Buckle between legs has one 6 Add more positions to fit more setting children References 1 Safe Ride News http www saferidenews com html Spec Amb html 2 Detroit News http www detnews com 2003 specialreport 0301 27 a11 68893 htm 3 Brazelton T University of Wisconsin Hospital and Clinics Interview 4 Physical Characteristics of Children http www itl nist gov iaui ovrt projects anthrokids child html Acknowledgements We would like to thank Dr Tom Brazelton and his colleagues and Biomedical Engineering Department for providing us an opportunity to work on this project Also we would like to thank our advisor Mitch Tyler for providing us feedback and pointing us in the right direction AMBUL ATORY CHILD SAFET Y SEAT