AUTOMOTIVE GLAZING : CURRENT & FUTURE TECHNOLOGY TRENDS

There may come a day when veterans of the auto glass industry gather youngsters around a cozy fireplace, to tell stories of how windshields used to be…..they’ll tell tales of the rhythmic melody of wiper blades that have since disappeared from the marketplace. Or maybe they’ll weave stories of how drivers “in the old days” actually wore sunglasses in cars to deflect the sun’s harsh rays while today the windshields themselves sport the equivalent of auto glass aviators.

The earliest windshields, introduced in 1904 was an option to protect the driver against wind, and when dirty - allowed the driver to tip the top half down for an unobstructed view. It was not until 1929 that the majority of vehicles were equipped with flat glass panels all around to provide protection from wind, rain, mud splashes, road dust, and flying debris. Curved side windows began to appear in the early 60’s, which meant more styling, design flexibility, and addition of built-in safety features.

Designers have always seen—and presumably will always see—glazing as a crucial element in designs that differentiate vehicles in the marketplace. In the recent years we see a marked increase in the amount of glazing in a car, in order to emphasize visibility and an "open cabin feel”. Two prominent design trends advocating these features are: Cielo (front & rear windshield extends up into the roof with sun-roofs morphed in) and Panoramic (front & rear windshields wrap into the sides to include ‘A’ and ‘C’ pillars). Innovative high-tech glazing solutions have been developed to minimize heat gain in vehicles and offer thermal comfort all year around, to reduce vehicle weight through the use of lightweight glazing, to provide maximum visibility for optimum driving conditions, to integrate new features that enhance the driving experience and to safeguard the vehicle occupants in case of accident.

Technology that will be essential in addressing the needs of automotive glazing over the next years and beyond will be determined by the dynamic trends in areas of energy, the environment, and aesthetics. These trends have become so universal that they have taken on the distinction of a “megatrend.” The Automotive Glass Industry is evolving to keep up with these trends, with some interesting technologies on the horizon.

CURRENT TECHNOLOGIES

Of all the new glazing technologies, Smart Glass has been in the limelightover the past year. ‘Smart glass’ is a general nickname for glass that has been made “smart” by adding some smart materials (either by coating or laminating) or by embedding electronics and sensors. Smart glass can provide a variety of capabilities for auto glass—self-tinting glazing, self-cleaning glazing, self-repairing glazing and enhanced in-car information and entertainment systems. SPD-SmartGlass (suspended particle devices) is a well-known self-tinting technology, in which a matrix polymer film filled with crystalline particles encased in a carrier fluid is sandwiched between sheets of glass, allowing the glass to be changed from clear to dark with the push of a button.One recent example of SPD’s successful application is in the 2012 Mercedes Benz SLK, which offers a panoramic roof switching to light or dark at the touch of a button. While UV and infrared light are effectively blocked in transparent mode, thermal insulation has been found to increase significantly in darkened mode, by dropping the temperature on interior parts by 80% : thereby taking the strain off the air-conditioning system, and leading to reduced CO2 emissions.

In Pininfarina’s design concept for ‘Hidra’ (a multipurpose coupe) - Marvel is an integrated windshield that heads off impending rainfall and tree twigs. In this prototype, Marvel is a nanotechnology-based 4-layered windshield designed to repel water and dirt without wiper blades. The top layer of this futuristic windshield contains titanium oxide which is designed to rapidly repel water, while the second layer directs dirt and debris off to the windshield’s sides. Although the windshield’s third layer is a sensor that calculates the amount of water or dirt that needs to be disposed, the commander-in-chief of the whole operation is the fourth layer. The final layer acts as a current conductor, charging the unit with electricity to run the entire self-cleaning process.

Gorilla Glass by Corning works great for smartphones, but what if you replaced all of car’s windows with this resilient stuff? Gorilla Glass is thin – from .5 mm to 2 mm – and therefore lightweight. But it’s also tougher and damage resistant. Its composition allows a deeper layer of chemical strengthening that is better able to resist the deep scratches that cause glass to break. Using Gorilla Glass in a car cuts down on the weight of the vehicle resulting in re-distribution of the weight reduction in a way that would slightly alter the car's center of gravity. Together, that would help cars with the new window glass gain a few extra miles out of each gallon of fuel. Recently, BMW has announced it will be using Gorilla Glass for the Rear Windshields of their i8 sports car for sound-dampening purposes, as the glass will consist of two 0.7mm layers with an acoustic sheet in the middle.

Polycarbonates – the Silent Revolution

One of the key plastics used in automotive sector is polycarbonate (PC). PC has dominated the market for vehicle headlamp covers for 15 years, and now it challenges glass in windows. The primary advantages of PC automotive glazing are 50% weight reduction (and associated CO2 emissions reductions) along with greater styling freedom and simpler functional integration.

European regulation currently permits polycarbonate (PC) use in all automotive glazing applications except the windshield. In the United States, the US Department of Transportation's National Highway Traffic Safety Administration (NHTSA) has approved the use of PC for all non-windshield glazing applications provided that it meets all existing auto glazing specifications for laminated glass as prescribed in the Federal Motor Vehicle Safety Standard (FMVSS) No. 205. However, uncertainty over long term weathering and compliance with the ANSI regulation has held back adoption of PC glazing in the US.

The wide choice of styling options with PC is testing conventional assumptions of automotive window design and creating whole new opportunities for advanced vehicle styling. Features such as colored glazing are now possible along with gaps in the window, sharp corners, smooth corner radii or complex 3D shapes. These features are undesirable, unmoldable or cost-prohibitive with laminated or tempered glass. PC auto glazing permits parts integration previously not possible. Using two-shot injection compression molding (ICM), it is possible to create a roof-module frame and optical panel in one piece. Molding heating/defrosting elements and fractal antennas into a PC window panel is also possible using in-mold films with preprinted circuitry.

Two principal PC suppliers and window glazing proponents, Bayer and Sabic Innovative Plastics, continue to make steady advances with resin and plasma coated polycarbonates. OEMs like GM, Ford, Volkswagen and Fiat have already started using these products for window and rear-glazing applications in passenger cars.

FUTURE TECHNOLOGY CONCEPTS

By 2020, the windscreen will display key information about speed, fuel and any issues with parts of the car. It will also combine visual sensors with augmented reality, online maps and GPS technology to provide drivers with live, visual information about the places and hazards around them. Essentially the car is becoming more like a laptop and the windscreen will evolve into the virtual information screen. Both glass and augmented reality technology are nearing a point where the windscreen can work harder to improve road safety, awareness and driving in general.

An interesting future possibility was showcased in the Smart Forvision concept : 129 hexagonal transparent dye solar panels fitted in the roof – that generates enough energy to power the car's multimedia electronics and three fans in the interior. When the car stands in the sun, the photovoltaic system powers the fans to keep the inside of the car cool. Because of their product features, dye solar cells have a major role to play in achieving regenerative, climate-neutral, safe and affordable energy for our future. Dye solar cells are proven to be extremely efficient even in cloudy conditions. The transparent dyes are stimulated by light and are very effective generators of electricity even in cloudy conditions. Hence, organic photovoltaics may actively help to improve the future performance of electric cars as an additional, sustainable source of energy. Transparent solar cells can also be manufactured in a virtually unlimited range of colors and act as a signature design element.

Got backseat boredom? General Motors and Toyota are working on a new concept in rear seat entertainment technology that uses the windows as interactive touchscreens - to help rear seat passengers (particularly children) have a richer experience on the road. General Motor’s Windows of Opportunity (WOO) Project and Toyota’s Windows to the World project were inspired by psychological studies indicating car passengers often feel disconnected from their environment, and are working to provide a technology interface designed specifically for rear seat passengers with interactive displays capable of stimulating awareness, nurturing curiosity and encouraging a stronger connection with the world outside the vehicle – with advanced windows that are capable of responding to vehicle speed and location that augment real world views with interactive enhancements to provide entertainment and educational value.

Augmented reality (AR) technology is seeping from our smartphones and creeping from our computers into the windshields of our cars. AR provides digital information layered on top of the windscreen, which can include pedestrian awareness alerts, directions and building identification labels. Although vehicle AR may seem like a far-off advancement, Heads Up Display (HUD) software is already implemented into cars. An interesting concept developed by Mercedes Benz called Dynamic and Intuitive Control Experience (DICE) is “capable of recognizing and using a driver’s hand movements to create a custom virtual dashboard—complete with live feed from their social network...” The display gives drivers the ability to pull up data pertaining to places of interest by simply pointing at them.

Another example of developmental AR is the enhanced vision system from General Motors which surveys the car’s surrounding landscape environment while simultaneously monitoring the driver’s eyes and head movements. The collected data is then processed onto the windshield to rely important information to the driver such as upcoming traffic, an animal near the side of the road or the identification of a building. This GM concept also has the capability of measuring distance from the car to the edge of the road when fog interferes with a driver’s view, a company report states.

However, the most extreme concepts being worked on are technologies that will make the front hood or back seat of a car appear transparent, so that the drivers can see everything around them. These experimental setups use cameras mounted outside the car to project an image inside the car in the driver’s field of view. Using similar technology to a heads-up display, the image is shown on a reflective screen mounted behind and between the two front seats. When a driver looks back over his shoulder, he sees the “real” image out of the rear view window continued, through augmented reality, right down the seats to the floor.

The Incoming Wave of Innovation: Embedded Interconnected Microsystems

As smart phones, watches and glasses become LEGO-like, customizable, micro-hardware assemblages that can be customized to meet individual and group requirements - embedded modular interconnected microsystems will also migrate into and greatly empower automobiles. The need to embed rapidly-evolving information, communication, entertainment and environmental devices is already straining existing models of driver safety and comfort requirements. The rapid expansion of in-vehicle functionality will be further compounded by innovations in intelligent vehicle glazing that would need to respond to gesture, voice and finally thought-commands through an intricate network of MEMS accelerometers, gyroscopes, pressure, temperature and flow sensors, microcameras, microactuators, microtransducers and more, along with their embedded microcontrollers and interconnection interfaces !