Folding Evacuation Sled for Patient Safety and Surge Capacity

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Solution Overview

Problem

Existing evacuation methods for non-ambulatory individuals in emergency situations, such as fires or earthquakes, fail to efficiently and safely move patients with varying needs across different terrains while maintaining medical care, and lack sufficient surge capacity post-evacuation.

Innovation Solution

A lightweight, strong, and versatile evacuation sled made from corrugated polypropylene, capable of folding into a compact configuration for easy storage and use, equipped with straps for maneuvering and carrying, and designed to provide temporary surge capacity as a bed post-evacuation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional evacuation methods are used for non-ambulatory patients, then patient safety during evacuation is compromised, but using specialized evacuation equipment increases device complexity and storage space requirements

Engineering Contradiction:
Improvepatient safety during evacuationVSAvoidevacuation device complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The evacuation device is divided into a sled portion and a bed portion that can be separated. The sled portion is used for evacuation while the bed portion provides post-evacuation care capabilities. This segmentation allows the system to address multiple needs (safe evacuation and ongoing care) without requiring a single complex device to perform all functions simultaneously.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The bed portion is designed to serve multiple functions: it provides structural support during evacuation, serves as a containment structure for the patient, and can be converted into a post-evacuation care bed. This multi-functionality reduces the need for separate specialized equipment for each phase of patient management.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Ease of operation

If lightweight and maneuverable evacuation devices are used to traverse difficult terrain, then ease of operation improves, but device strength and rigidity may be compromised

Engineering Contradiction:
Improvemaneuverability on terrainVSAvoiddevice rigidity
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The sled portion is designed with specific local qualities: a low-friction bottom surface for easy movement across terrain, while the sides and structure provide necessary containment and support. The differential wheel assembly provides localized mechanical advantage at contact points with the ground, enabling maneuverability without requiring the entire structure to be heavy or complex.

Inventive Principle:
Principle #3Local quality

3Reliability

If evacuation devices are designed to protect patients with special needs and injuries, then patient protection improves, but device weight and complexity increase

Engineering Contradiction:
Improvepatient protection during evacuationVSAvoidevacuation device weight
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The sled portion incorporates a cushioned surface that contacts the patient, providing protection from rough terrain and jostling during evacuation. This cushioning is integrated into the basic structure rather than added as a separate heavy protective layer, maintaining lightness while ensuring patient protection.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

4Reliability

If facilities maintain evacuation devices for rare emergencies, then emergency preparedness improves, but storage space and manufacturing costs increase

Engineering Contradiction:
Improveemergency preparednessVSAvoidstorage space requirement
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The bed portion is designed to fold flat, transitioning from a three-dimensional volume-consuming structure to a two-dimensional flat package. This allows the device to be stored in otherwise unused spaces such as under beds, mattresses, or in closets, effectively utilizing vertical and unused horizontal spaces rather than requiring dedicated storage rooms or large storage areas.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables rapid, safe evacuation of patients with diverse needs across various terrains, including stairs, and doubles as a temporary bed to address surge capacity needs during emergencies, reducing the need for extensive staff and storage space.

Implementation Method 1

The surfaces of the sled may be manufactured from a single piece of material... A lightweight, strong, sturdy, and versatile evacuation sled is described

Methodology Applied
Scientific EffectMaterial strength:

Implementation Method 2

The surfaces of the sled may be manufactured from a single piece of material, stored flat, and then folded into the sled's functioning configuration

Methodology Applied
Scientific EffectFolding: Folding

Implementation Method 3

The sled has a low coefficient of friction and is lightweight. This allows the sled to be readily moved and handled without requiring the assistance of multiple people

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 4

The sled may be readily towed with a towing harness and may be moved down an incline, such as stairs

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP2057057B8Evacuation sled and temporary surge capacity bed
Publication Date: 2012.03.14 STRYKER CORP

AI summary

A lightweight, strong, sturdy, and versatile evacuation sled is disclosed. The body of the sled may be manufactured from a single piece of material, stored flat, and folded into its functioning configuration. When folded, the sled has one or more straps that help hold it in its folded configuration and allow maneuvering or carrying the sled. The sled may be readily towed with a towing harness and may be moved down an incline, such as stairs, by means of a rope and belay device. The sled has a low coefficient of friction and is lightweight, allowing the sled to be readily moved and handled without requiring the assistance of multiple people. Additional sleds with foam inserts may be provided to carry equipment such as for life support. The sled may also provide surge capacity for facilities like hospitals, as the sled is designed to be inexpensive and essentially disposable.