Vehicle Rocker Panel Side Rail Stiffener Partitions

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current motor vehicle floor structures are inadequate in absorbing the energy of severe side impacts, particularly at 32 km/h with a 75° angle, which can lead to significant deformation and risk of injury due to limited energy absorption capabilities.

Innovation Solution

The proposed motor vehicle structure features U-section side rails with integrated U-shaped stiffener sections and transverse partitions that form vertical junction planes, allowing for enhanced energy absorption through staggered and closely spaced connections between the U-sections and stiffener profiles, which are strategically positioned between crosspieces to support front seats and extend along the length of the spar.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If conventional floor structures with cross members are used, then the structure is simple and easy to manufacture, but the energy absorption capability during side impact is insufficient

Engineering Contradiction:
Improveenergy absorption capabilityVSAvoidstructural complexity
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The U-shaped stiffener is nested inside the U-shaped main profile, with the stiffener housed within the hollow section formed by the main profile. This nesting arrangement allows the stiffener to be integrated into the existing structure, maximizing space utilization and improving energy absorption without significantly increasing external dimensions or manufacturing complexity

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The stiffener is divided into multiple segments by transverse partitions that create separate hollow sections along its length. This segmentation allows each section to independently absorb impact energy while maintaining overall structural integrity, and enables modular manufacturing and assembly

Inventive Principle:
Principle #1Segmentation

2Use of energy by moving object

If the stiffener is placed far from the floor to maximize protection, then energy absorption is improved, but the structural stiffness and resistance to deformation are reduced

Engineering Contradiction:
Improveenergy absorptionVSAvoidstructural stiffness
Core Design Contradiction:
Use of energy by moving objectVSStrength

Solution Approach 1:

The stiffener is positioned with its web adjacent to the floor structure at critical impact zones, providing localized reinforcement where it is most needed for stiffness. The transverse partitions create regions of varying stiffness along the stiffener's length, with closer spacing near the floor to maximize local reinforcement and greater spacing elsewhere to maintain energy absorption capacity

Inventive Principle:
Principle #3Local quality

3Use of energy by moving object

If closely spaced transverse partitions are used, then energy absorption is enhanced, but manufacturing complexity and material usage increase

Engineering Contradiction:
Improveenergy absorptionVSAvoidmanufacturing complexity
Core Design Contradiction:
Use of energy by moving objectVSEase of manufacture

Solution Approach 1:

Transverse partitions are implemented at selective locations rather than continuously along the entire stiffener length. The partitions are concentrated in regions where impact forces are most likely to occur, providing sufficient energy absorption enhancement while avoiding the manufacturing complexity and material costs associated with continuous partitioning

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3209537B1Side rail of vehicle rocker panel with stiffener and partitions
Publication Date: 2019.05.22 PSA AUTOMOBILES SA
  • EP3209537B1 patent drawingFigure 1~3
  • EP3209537B1 patent drawingFigure 4~5

AI summary

The invention relates to a motor vehicle structure (8) with a floor and two rocker panel side rails (12), each of the side rails extending in a main direction and comprising: two main profile members (20; 22) having a U-shaped cross-sections arranged with the openings thereof opposite one another in a horizontal direction, and attached to one another; each of the side rails (12) comprise, in addition: a stiffening profile member (24) with a U-shaped cross-section, housed in the side rail (12) and with tabs for attachment to the ends of the U attached to an inner side surface of the main profile member (20) located on the outer side of the floor; at least one and preferably a plurality of partitions (26) arranged transversely in the side rail (12) between the stiffening profile member (24) and a side inner surface of the main profile member (22) located on the side of the floor. The invention also relates to a motor vehicle comprising such a structure (8).