Electroactive Polymer Transducer Tear Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Compliant electroactive polymer transducers often experience premature and unpredictable failures due to tear propagation, which affects their reliability and consumer confidence, and the underlying causes of these failures are not well understood.

Innovation Solution

The implementation of compliant tear-resistant treatments and layers applied to the electroactive polymer transducers, either proximate to the edge portions or covering large surface areas, as well as adding material outside the active area to reduce stress and strain variations, helps prevent tear propagation and enhance transducer lifetime.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If compliant electroactive polymer transducers are used to enable larger deflections, then application versatility is improved, but reliability deteriorates due to premature and unpredictable tear propagation failures

Engineering Contradiction:

Improveapplication versatilityVSAvoidtransducer reliability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies tear-resistant treatments and layers to the electroactive polymer transducer before it is put into service. These preventive measures are incorporated during manufacturing to stop tear propagation before it can cause failure, thereby improving reliability without affecting the compliance and versatility of the transducer

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces intermediary tear-resistant layers and treatments between the electroactive polymer and the external environment. These intermediary elements act as protective barriers that prevent tear propagation while allowing the transducer to maintain its compliant properties and functional versatility

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If tear resistant treatments and layers are applied to the transducer, then reliability is improved by preventing tear propagation, but device complexity increases

Engineering Contradiction:

Improvetransducer reliabilityVSAvoidtransducer structure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies tear-resistant treatments and layers selectively to specific regions of the transducer where tear propagation is most likely to occur, such as edge portions and high-stress areas. This localized approach improves reliability at the critical locations while minimizing the increase in overall device complexity

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses thin film tear-resistant layers and compliant treatments that conform to the transducer surface. These thin films provide protective functionality without adding significant structural complexity or rigidity, maintaining the transducer's compliant characteristics

Inventive Principle:

Principle #30Flexible shells and thin films

3Duration of action of stationary object

If added material is provided outside the active area to reduce stress variations, then durability is improved, but manufacturing complexity increases

Engineering Contradiction:

Improvetransducer lifetimeVSAvoidmanufacturing simplicity

Core Design Contradiction:

Duration of action of stationary objectVSEase of manufacture

Solution Approach 1:

The patent divides the transducer structure into functional segments: the active area for energy conversion and the added material regions outside the active area for stress management. This segmentation allows the added material to be manufactured and integrated as a separate component, simplifying the overall manufacturing process while extending transducer lifetime

Inventive Principle:

Principle #1Segmentation

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

These solutions effectively increase the lifetime and reliability of electroactive polymer transducers by preventing tear propagation and reducing stress and strain variations, leading to improved performance and extended usage without compromising the transducer's compliance and performance.

Implementation Method 1

an electroactive polymer for converting between electrical and mechanical energy

Methodology Applied

Scientific EffectElectrostatic actuation: Electrostatics

Implementation Method 2

compliant means for preventing a tear from propagating in the electroactive polymer

Methodology Applied

Scientific EffectMechanical coupling:

Implementation Method 3

The added material is configured to reduce stress or strain in electroactive polymer material outside the active area when the electroactive polymer transducer is deflected or pre-strained

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Data Source

PatentUS7804227B2Tear resistant electroactive polymer transducers

Publication Date: 2010.09.28 SRI INTERNATIONAL

AI summary

Described herein are several solutions that increase transducer lifetime by reducing or preventing tear propagation in a compliant electroactive polymer. One solution couples a compliant tear resistant treatment to a transducer proximate to an edge portion of the electroactive polymer. Another solution uses a tear resistant layer that couples to and covers a large surface area of the transducer. Another suitable tear resistant solution provides added material outside an active area; the added material reduces stress or strain variations in polymer material outside the active area when the electroactive polymer transducer is deflected or pre-strained.