Please Click Smart Polymer Applications to view original article in full by Dr. Donald V. “Don” Rosato President of PlastiSource, Inc
Properties inherent in shape memory polymers (SMP) and other smart polymers have the potential to be game-changers in the automotive field. These advanced materials may eventually lead to vehicle subsystems that can self-heal in the event of damage, or that can be designed to change color or appearance.
SMPs in automotive applications can open new opportunities for variable features in vehicles. The novel materials add new high-tech features while improving vehicle performance at lower cost.
SMP actuators and sensors can replace small electric motors or hydraulics with ability to use a simple device to produce specific mechanical action in response to specific conditions or signals can dramatically improve the overall performance of a device.
Shape-changing materials in place of motors can:
- Reduce vehicle mass and component size/complexity
- Increase reliability/improve vehicle performance
- Improve fuel economy
SMPs also improve design flexibility. Designers can use these materials to simplify products, add features, improve performance or increase reliability with relatively little mechanical complexity. The new materials permit functionality to be “programmed in” to facilitate inventive designs, enhance efficiency, and provide new and advanced features.
They allow the addition of movable elements in applications impractical for motors. They also enable new functionality and convenience/comfort features. SMPs/alloys are among smart materials in development by the General Motors Corporation (GMC).
Looking to revolutionize their car design, GMC refers to the new shape memory polymers and alloys as promising “game-changers” in automotive advanced materials. These new materials have the potential to change the look and feel of GMC cars and trucks and even eventually lead to automotive subsystems that can self-heal when damaged, or can be designed to change color.
One possible application is in air dams and louvers that adjust to govern airflow, improving aerodynamics and performance. The air louver concept on the Chevy Volt that controls airflow into the engine compartment is a good example. Using shape memory material, the air louvers adjust to govern airflow, remaining closed to speed warmup during cold starts and opening wider to let in more air as the engine heats up.
The heat-activated smart material operating the louver uses the under-the-hood temperature as the basis for the vents opening. Heat contracts the shape memory material causing the louver blades to rotate to an open position when the under-the-hood temperature reaches a predetermined temperature.
Shape memory material “first generation” applications being tested include:
- Automatically adjusting air vents that let in more air.
- Aerodynamic front air dams that retract when not required
- On-demand rear spoiler
- Interior grab handle that automatically unfolds to facilitate vehicle entry
- More accessible engine hood, door latch, glove compartment releases
- Smart emergency brake release
- Rain-activated automated wipers
- SMP and alloy stiffening panels
- Self-healing panels/bumpers
