Crushable Armrest Assembly for Side Impact Energy Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current vehicle door armrest assemblies fail to effectively absorb and distribute the forces encountered during side impact crash tests, such as those standardized by IIHS and NHTSA, leading to inadequate protection and potential injury.
Innovation Solution
The armrest assembly incorporates a crushable member with a substrate and a plug fixed to its perimeter, designed to absorb forces by crushing, featuring an X-shaped gap and an elastomer plug that enhances energy absorption and meets crash test standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the armrest assembly uses a rigid structure, then structural strength is improved, but force absorption and energy dissipation during side impact crash tests deteriorate
Solution Approach 1:
The armrest assembly incorporates a crushable member with controlled material properties that transition from rigid to crushable under impact conditions. The substrate and plug are designed with specific mechanical properties that allow them to maintain structural integrity during normal use but crush and absorb energy during side impact crashes, resolving the contradiction between strength and energy absorption
Solution Approach 2:
The crushable member is constructed as a composite structure with a substrate and a plug made of different materials. The substrate provides structural framework while the plug material (with different hardness and elasticity) provides energy absorption capability. This composite design allows the armrest to exhibit both strength and force absorption characteristics simultaneously
2Ease of manufacture
If the armrest assembly uses a simple structure, then manufacturing complexity is reduced, but crash test performance and force distribution capability deteriorate
Solution Approach 1:
The armrest assembly is divided into distinct components: a substrate, a plug, and a foam pad. The substrate and plug are further segmented with gaps and ridges to control crush patterns. This segmentation allows each component to be manufactured separately using standard processes while achieving complex crash performance characteristics when assembled
Solution Approach 2:
The crushable member incorporates a substrate with gaps and ridges creating a porous-like structure that controls the crush progression. This geometric porosity allows the structure to collapse in a controlled manner during impact, improving crash test performance without requiring complex manufacturing processes
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
The described armrest assembly improves lateral crush performance in side impact crash tests by effectively distributing and absorbing forces, enhancing vehicle safety and compliance with crash test regulations.
Implementation Method 1
The plug may be formed of an elastomer
Implementation Method 2
The crushable member may extend from the door trim panel transversely to the door trim panel, and the crushable member may be designed to crush toward the door trim panel
Data Source
AI summary
An assembly includes a door trim panel, and an armrest assembly supported by the door trim panel. The armrest assembly includes a crushable member. The crushable member includes a substrate defining a gap extending through the substrate. The crushable member includes a plug disposed in the gap and fixed to the substrate on a perimeter of the gap. The substrate is rigid relative to the plug.