Auto Reviews, Tips and Guide

Automotive glass ceased long ago to be just a window. The opportunity to produce complex shapes and curves while maximizing visibility is there to be exploited by designers. Indeed, over the last three years, the design complexity of windshields and backlights has increased to a new level in terms of cross curvature and compound radii.

At Pilkington we are starting to identify physical limitations with these designs, particularly with windshields, in terms of meeting EC regulatory and customer optical standards. For example, even if it is feasible to manufacture the glass, there can be natural optical effects arising from the glass shape in the motorist’s view through the windshield causing them to see secondary images (figure 1). The EC legislation states that the distance between the two images should be no more than 15 minutes of arc in the primary vision area (see figure 2) but customer standards can be more restrictive.

The trends towards increased cross curvature of windshields can be seen by the fact that 10 years ago the average cross curvature of a windshield was 10-15mm, five years ago it was 15-20mm but now it can be anywhere from 20-50mm. Any designs that exceed 30mm need to be considered very carefully for secondary images.

The styling of backlights is also becoming more complex. The vision through the rear view mirror is becoming increasingly restricted as styling features progressively reduce the useable vision area. Unlike windshields, there are no regulatory controls over optics on backlights so vehicle manufacturers need to be able to get an idea of the level of distortions that are acceptable to meet their own specifications.

This means that the days of the vehicle manufacturer stylists creating rigid design specifications delivered as fait accompli to system makers are well and truly over. The only way to match ever shorter development times with reduced costs, while still delivering the quality and accuracy which today’s discerning consumers demand, is through simultaneous engineering with vehicle stylists. Quite simply, system manufacturers need to become partners in vehicle design.

Pilkington’s European Simulation Centre makes it possible to develop this partnership. Using the latest computer modeling techniques, we are using this approach to great effect with most of the world’s major vehicle manufacturers.

Recent examples are the Ford B-Car platform, which includes the Fiesta, Ka and the Fusion sports utility vehicle for Europe, and the Volvo P2 platform, comprising the V70, S80 and S60. Simulation technology was used to optimize designs for the Ford B-Car in both Europe and South America so cost targets could be met while realizing the original styling intent. For the P2 platform, the windscreen and backlight were crucial to the overall design so simulation technology was used to check the feasibility of the glazing design.

The vehicle stylist who uses glass in increasingly complex curvatures, creases and wraparounds, has not always appreciated the implications of such design features with a material that is shaped either by sagging or pressing at furnace temperatures up to 650_C and which can lose optical integrity if it is bent into a complex shape.

Through the latest finite element modeling techniques, the European Simulation Centre based at the Pilkington Technical Centre, Lathom, UK, is able to offer early value engineering reviews and validation of engineering design to manufacturers. The ability also exists to forecast any possible optical effects both from the original CAD surface and from the shaping process. Optical distortion in glass manufacture emanates from both ‘stretching’, causing a local reduction in glass thickness, and from an excess of glass causing wrinkles or buckling.

Computer images show how the design surface will perform optically against an outside scene just as a driver or passenger would see them when looking through a manufactured windshield or backlight. This can be extended to include the manufactured surface.

With regard to the process, engineers used to have to rely on trial and error to predict the precise tool shape needed to manufacture the desired curvature. Now Pilkington is able to predict correctly first time, with a near 100% success rate, the flat glass size to give the correct bent size as well as tool design for new glazing. This advanced shaping development means any features likely to cause imperfections can be identified and eradicated before prototype production. This results in further advancements in optical vision integrity and therefore a safer environment for the motorist as well as greatly reducing prototyping time and costs for vehicle manufacturers.

The simulation centre can also be used for benchmarking. For example, in predicting backlight vision distortion (see figure 3), it can indicate potential problems with quantified distortion values and refer customers to existing glasses which they can use as a benchmark.

The trend towards providing all round laminated glazing as an option on an increasing number of vehicles requires detailed discussions with glazing systems manufacturers. Using two layers of glass, which may need to be semi toughened, will affect the optical quality and feasibility of the design. Where vehicle manufacturers are looking to provide the option of a laminated backlight, this may not always be possible with the more complex designs. It is important to assess feasibility in the early stages, not once the vehicle has already gone into production. Pilkington can help to evaluate whether laminated glazing can be an option and also whether other features such as solar control films are feasible.

Simulation can reveal within a matter of days whether a bold new shape will work. The team often suggests a modification to a proposed glass profile in order to ensure optical correctness and production and cost feasibility, while staying within the styling intent.

But such savings in time and money and the twin agreement on optical quality and manufacturing feasibility are possible only though co-operation and discussion even before the ‘clay-model’ stage of vehicle design. Once the bodywork is fixed, it is often too late to make anything other than minor changes to the glazing. Early involvement and the development of the partnership relationship is providing benefits all round. It means that Pilkington is able to express its views on the impact on glass of particular vehicle shapes sooner, rather than later when almost all the design decisions have already been made. More and more we would like to work towards the vehicle manufacturer working with us to design the product that fulfils the model criteria, rather than giving us a drawing with the specification already determined.

At Pilkington we are already educating future vehicle designers about the feasibility of their designs and the optical standards they have to meet through a lecture programme as part of our ongoing award sponsorship of the Royal College of Art’s vehicle design group. The awards are aimed at encouraging post-graduates to explore the strengths and limitations of glass in vehicle design while providing strong links between academia and industry. Industry experts judge designs on real life criteria, making the awards a valuable exercise for young designers who will go on to hold senior industry positions.

Buying a used motorcycle is like buying a dog. W? While most people like the new, cuddly toys, can be brought much new work. Used? with a dog, the puppy is essentially a B? Teeth, it is g? N? Ally broken? S and the house will not m? Expensive either on your business. A v? Used lo? is pr? t and f? Trekking the long R? Are? More countries accident? and? the n? Week Chste rally you to visit the dying. New motorcycles with new if? Leather brand management can still grin? Ant and evil? ease, a bit like the baseball glove leather f you work?? R hours, the leather is soft to the touch. The What If? Management of used motorcycle have? J? softened and pr? t f? A long journey in comfort and style. Bew? Companions Motorcycles opportunity to unite? S tend? all folds have? t? ? Labor? S. When there is an R? I return, it will be much EN? H in the life of a new motorcycle. Although the probability? a T? Dlicher Unf? It? With a new bike are tr? S thin, each new technology ap? Period of incubation. Buying a used motorcycle you pass? that new technologies? B? Hne and opaque with technology hrte. M? Me many Sch? Es can? Silent produced by a car, see you still remember the technology used? Sw? While a bike is not complete? Ment? Constantly the W? Ldern in terms of m? Possible points, there is less chance that a back R? me one? Snack mod? The big enough? Be taken. Cheaper Accessories Most bikers do not sell their used motorcycle accessories? removed? of used bikes? they’re selling. There are several Gr? Daf Nde? R. One reason is that often the F? D-operation of Russia accessory? R is the bike? T? bought, e, can k? Used? S do not match? the new bike. In this way? It, k? Can you lot? About Dr. accessories are on a motorbike use?’re Simply purchasing the bike. Sometimes Accessories on a motorcycle is? the price alone, m? Ber without me? Cksichtigung co? T bicycle. Some saddlebags can co? B up? $ 500 or more, depending on her? Is that it is individual. A painting personalized? E on a motorcycle is helpful? could you co? ter thousands of dollars. A used motorcycle has handlebars personalized? Bars Cruiser hinzugef say? Have? T? ins? r? s, may be worth a good quantity? money, depending on brand and style handlebar. Accessories can be brought a good motivation f? R is the choice of a used motorcycle. Price Gro? In Because it is a used motorcycle, you can find offers sp? Sions. If you have a mod? The brand you? Your Particular rately int? Ress? ? find k? You can search and compare the offers and find the best deal. With a used motorcycle, if you walk? T? pay a certain price, many used bikes? es g? rer suppliers, if you have a price? mind and it is Vern? Nftig. In this way? It, you could bestm? Like? prices, w? Then a new bike has a fixed price and usually there is no n? Tiations with the price. A v? Used lo? can be brought a Schn? Be headset.