NEW PRODUCTS: Volvo CE’s Hamelin plant in northern Germany rose to the rare challenge of designing a new machine range from scratch – the DD105 asphalt compactor
by Nigel Griffiths
While its three-year development involved a Volvo-wide design effort, the DD105 asphalt compactor made its debut at the Intermat show in Paris with ‘Made in Hamelin’ stamped firmly on its side. The product development team called upon Volvo assets worldwide, yet the main inspiration and engineering expertise was to be found in-house based at the company’s plant in Hamelin, the historic town made famous by the Middle Ages legend of the Pied Piper.
“In early 2012, we were analyzing the product offering from our competitors and saw that there was a gap in the market for a new Volvo product range. So we set about designing a new machine,” explains systems engineer Michael Kreische. “Starting with a blank sheet of paper, we were able to sit down and decide exactly what the owner and operator would want.”
The end result is the DD105, a 10-tonne double-drum vibratory asphalt compactor. “It is the first of a completely new generation of asphalt compactors for the European market,” explains Senior Global Market and Launch Manager David Herwarth von Bittenfeld. “They are designed to achieve industry-leading fuel efficiency combined with high productivity and performance.”
EYE FOR DESIGN
Asphalt compactors are used in the final and critical stage of finishing a new road surface. In terms of both functionality and aesthetics, the finish has to be perfect.
The workforce at the Volvo CE plant in Hamelin has been building road-surfacing machines for more than 65 years and the location is a center of engineering excellence in this sector.
Key features targeted by the Hamelin design engineers were operator visibility, serviceability and, of course, fuel efficiency. “The operator of an asphalt compactor needs to see the drum rollers and spray system clearly both in front and behind. Any contamination can ruin the surface finish,” explains product manager Antonio Romao.
“At the concept stage, our engineers were able to consider major design issues, such as placing the engine behind the cabin to reduce noise and vibration and, vitally, to improve the operator’s sight lines. A key design feature has been the use of a pedestal frame and a pillar-free forward view to give the operator unhindered visibility.”
Another important design consideration has been operator control and comfort. The large expanse of curved glass provides superb unobstructed visibility down to the drum and spray bars, thus assuring rolling precision. The operator seat slides or rotates to further improve visibility according to requirements.
To facilitate easy access to key engine components for maintenance, a flip-up hood has been designed for the engine located behind the cab. Padded floors in the cab further reduce vibration and minimize operator fatigue.
A major feature of the DD105 design process was building a full-size prototype from wood. “This allowed us to evaluate the real size and space aspects,” says Volvo CE’s design director Sidney Levy. “It allowed us to quickly sort out many design issues and come up with a few new ideas. This exercise enabled designers to check the operator sight lines. It even showed that operators needed more steps to get into the cabin.”
During the three years of development work the design team relied upon Volvo resources as far afield as India and the United States to help develop the DD105 in areas such as engine, cabin design and software.
Fuel efficiency was a key consideration – the DD105 is equipped with an advanced Stage IV Volvo D3.8 engine which optimizes fuel consumption while minimizing noise and emissions. The ECO mode reduces fuel consumption by up to 30% without affecting performance. The auto-idling feature automatically reduces engine speed to idle after five seconds.
In addition, a new vibrator system in the roller with an off-center design uses less power and is quieter for the operator. The amplitude of the vibrator can be customized according to the road application.
When designing an asphalt roller, in addition to safety and fuel efficiency, ergonomics and the user experience will always be core attributes for any Volvo designer,” adds Levy.
“In developing the DD105, it was important to understand the user-movement patterns in the cab and eventually reflect them in the design. Features like the sliding seat and easy-to-open windows will ensure operator efficiency and comfort even in tough weather conditions.
“With the design of the DD105, we also continued our approach of readdressing the proportion of yellow to grey and we were able to add features which make the machine look more dynamic and match its performance visually. You almost feel you can see it performing,” says Levy. “The Volvo CE design team has accomplished a striking design with the DD105 which is both functional and contemporary. It is unmistakably Volvo.”