Granular Jamming Mandrel for Composite Curing Support

Solution Overview

Problem

Existing mandrels used for composite part processing, particularly in out-of-autoclave scenarios, fail to conform to internal geometries and reduce in size effectively, as inflatable bladders are not suitable for varying temperature and pressure conditions.

Innovation Solution

A mandrel system comprising a first bladder with granular material that exhibits jamming when air is removed, and a second bladder that expands to apply force to the first bladder, allowing it to conform to internal cavities and provide rigid support, which can be reduced in size for easy removal.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If an inflatable bladder is used to support a composite part during autoclave curing, then the part can be supported under autoclave pressure, but the bladder is not suitable for out-of-autoclave curing conditions with different temperature and pressure

Engineering Contradiction:

Improveadaptability to different curing conditionsVSAvoidreliability of support function

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the physical state of the support material by transitioning granular material between jammed (rigid) andunjammed (fluid) states through air pressure changes. This allows the same mandrel to adapt to different curing conditions (autoclave vs. out-of-autoclave) by adjusting the air pressure to control the material's mechanical properties, thereby achieving both adaptability and reliability across varying temperature and pressure environments.

Inventive Principle:

Principle #35Parameter changes

2Shape

If a rigid cure tool/mandrel is used to support composite material during curing, then the part geometry is maintained, but the mandrel cannot conform to complex internal cavity geometries

Engineering Contradiction:

Improveconformability to internal geometryVSAvoidrigid support capability

Core Design Contradiction:

ShapeVSStrength

Solution Approach 1:

The patent employs a dynamic support system where granular material transitions between fluid and rigid states. During insertion and conforming phases, the material behaves as a fluid to match complex cavity geometries. During curing, air pressure induces granular jamming that transforms the material into a rigid state, providing necessary structural support. This dynamic state change allows the mandrel to simultaneously achieve conformability and rigid support capability.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the physical state of the support material by transitioning granular material between jammed (rigid) andunjammed (fluid) states through air pressure changes. This allows the same mandrel to adapt to different curing conditions (autoclave vs. out-of-autoclave) by adjusting the air pressure to control the material's mechanical properties, thereby achieving both adaptability and reliability across varying temperature and pressure environments.

Inventive Principle:

Principle #35Parameter changes

3Strength

If a supporting bladder is inflated to provide rigid support during processing, then the part geometry is maintained, but the mandrel cannot be easily removed after processing

Engineering Contradiction:

Improverigid support capabilityVSAvoidease of removal

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The patent changes the physical state of the support material by transitioning granular material between jammed (rigid) andunjammed (fluid) states through air pressure changes. This allows the same mandrel to adapt to different curing conditions (autoclave vs. out-of-autoclave) by adjusting the air pressure to control the material's mechanical properties, thereby achieving both adaptability and reliability across varying temperature and pressure environments.

Inventive Principle:

Principle #35Parameter changes

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 system effectively supports structural members during processing by conforming to internal geometries and providing rigid support, while allowing for easy removal post-processing by deflating the second bladder.

Implementation Method 1

a first bladder containing a material, the material being capable of exhibiting granular jamming when air is removed from the first bladder

Methodology Applied

Scientific EffectGranular jamming:

Implementation Method 2

a second bladder configured to expand and apply a force to the first bladder

Methodology Applied

Scientific EffectGas compression and expansion: Compression

Data Source

PatentUS11001014B2Mandrel for supporting structural member during processing

Publication Date: 2021.05.11 THE BOEING CO

AI summary

Within examples, a mandrel is configured to be inserted into a cavity defined by an interior wall of a structural member to support the structural member during processing. The mandrel includes a first bladder containing a material, the material being capable of exhibiting granular jamming when air is removed from the first bladder. The mandrel further includes a second bladder configured to expand and apply a force to the first bladder. Systems and methods that relate to the mandrel are also described within examples.