Webasto LigHT Concept

Panoramic roof system

By Grant Edwardson
March 4, 2008 11:03 AM
Filed Under: European, Specialty Marques

Built to showcase it’s expertise in designing and producing vehicle convertible/glass roof systems, Webasto’s LigHT concept is based on a Roadster design. Webasto refer to its roof design as the “Light Hybrid Top” hence the capital “H” and “T” in LigHT.

Webasto have long been a favourite source of rooftop design for the automotive world. Such exclusive contracts include being involved in the Mini convertible and the VW Eos. Who could forget all those VW campers of the 70’s with their fold up Webasto roofs and sunroofs.

Their new design is a combination of soft top and hard top which utilises a new mixture of materials such as lightweight polyurethane and polycarbonate. The unit on the concept only weights approx 14kg.

The convertible design has long been a perennial favourite in many markets. Increasingly manufacturers are basing their convertible design on modified family saloons and hatchbacks and Webasto are clearly trying to stay ahead of the game with their new design. With summer just around the corner, Geneva seems like a great place to preview their new technology to the automotive giants of this world. Read on for more technical details.

Source: Webasto

Press Release (Click to expand)

Webasto presents new roof concept in Geneva: Webasto LigHT (Light Hybrid Top) Concept Based on a Roadster design study Webasto presents its LigHT concept - a Light Hybrid Top with a new mix of materials

Stockdorf/Munich (Germany) - February 29, 2008 - In keeping with the motto, "Moving Innovations" Webasto presents a new category of roof design for convertibles at the 78th International Motor Show in Geneva; the Webasto LigHT Concept. The innovative roof system is a so-called Hybrid Top - an intelligent combination of the soft top and the hard top, utilizing a new mix of materials. Beyond that, the roof system is distinguished by a combination of lightweight polyurethane and polycarbonate components. It only weighs approx.14 kg in the design model. The vehicle design is based on a classic Italian roadster.

"The description LigHT reveals the essential key to this roof system", said Franz-Josef Kortüm, Chief Executive Officer of Webasto AG. "We are using it to show for the first time what an innovative, simple and light hybrid top could look like when a retractable hard top is combined with a soft top. What is of additional interest is the attractive price."

With its Webasto LigHT the company offers a glimpse into the future, foregoing the use of classic convertible top kinematics. Whereas metal rods and joints provide stability on conventional roof systems, here Webasto relies on self supporting surface cross members connected by film hinges. Apart from these film hinges the LigHT Concept only has one additional rotational point, which is used for moving the roof. The result is a forward-looking Hybrid Top: a combination of retractable hardtop (RHT) substructure with the stylistic impression of a soft top.

The entire substructure is manufactured in one piece - important for stability and making it easy to open manually. Websto has already developed a possible electromechanical opening mechanism. Another innovative detail of Webasto LigHT - the continuous fabric panel only ends at the joint to the trunk lid.

When opened, the roof is positioned on the rear section of the car and integrated harmoniously into the surrounding surfaces. The roof does not take up any space inside the car and hence does not affect the size of the trunk.

The project was conducted in cooperation with IED Automotive, a professional spin-off of the Italian design school IED (Istituto Europeo di Design). The concept car was styled by Andrea Militelo, Chief Designer of IED Automotive.

Innovative material mix: polyurethane and polycarbonate

The surface elements of the roof are produced using Compound Spray Moulding (CSG), stemming from the further development of Webasto's series-tested polyurethane technology, which achieves a very good weight-to-rigidity ratio. Since polyurethane combined with paper honeycomb-like structures weighs far less than conventional solutions, very light and robust roof systems can be realized in one piece.

The rear window is a scratchproof, coated polycarbonate (PC) panel produced in an in-mould decoration process. The material is very transparent and wear resistant. Polycarbonate windows absorb 100 percent of UV radiation and do not splinter in the event of an accident. Thanks to the newly developed heating function, they achieve defrosting speeds comparable to a glass window.

Webasto is one of the leading automotive suppliers using the plastic technologies polycarbonate and polyurethane. The company operates its own synthetics facility in Schierling near Regensburg (Germany). This is where currently biggest polycarbonate automobile roof (1.2 square meters) is being produced for the smart fortwo. Up to now more than 100,000 have been built.

Other topics of the business segment Convertible, Roof & Body at the Webasto stand (hall 5, stand 5132):

Three creative and dynamic convertible models in a scale of 1:4 also give you a glimpse of the automotive future. They are the result of cooperation between Webasto and the Faculty for Design at the University of Munich. Under the motto of "The Roof of the Future", up-and-coming designers developed innovative roof systems on other vehicles than simply just roadsters and coupes.

Panorama glass roof of the new Audi A4 Avant: The bottom load panorama roof of the new Audi A4 Avant was implemented in a modular framework concept - a real novelty in terms of modular mechanics. The front panel of the glass roof moves out, while the rear panel remains fixed. The roller blind is controlled at the sides by electric drives and is infinitely adjustable. The winding shaft for the roller blind is located above the trunk, optimizing the package, and the rear passengers benefit from improved headroom. The blind can also be closed when the roof is open and serves as a wind break. Apart from this, a new windshield made of stretch fabric is integrated into the panorama glass roof, which not only looks excellent but also ensures optimum acoustic characteristics. The integrated outside trim at the front of the roof panel reduces wind noise, particularly when the roof is opened to let in fresh air. The glass area is more than 0.82 square meters, the transparent area is more than 0.5 square meters, and the front panel can be opened completely.