Dec 8, 2008

Delcam’s PowerSHAPE used for customised manufacturing of motorbike helmets

Delcam’s PowerSHAPE CAD software has been used for the customised manufacture of motorbike helmets as part of the Custom-Fit project, the largest research project into rapid manufacturing in Europe. The helmets used a customised liner, which enables a standard helmet to give better fit and comfort to the rider.

Custom-Fit is an industry-led, research project supported by the European Community and coordinated by Delcam. With a total of budget of 16 million Euros, including a funding of more than 9 million Euros from the Commission, both the project members and the Commission believe that the project outcomes will benefit both society and industry in Europe.

The members of the consortium are made up from a broad base of organisations across Europe, in the fields of manufacturing, design, scanning, materials and consultancy. The aim of the project is to develop systems for the production and supply of personalised custom products or components.

Studies performed within Custom-Fit have shown that 15 to 20% of all full-face composite helmets are ill fitting and that 5% of motorcyclists cannot find helmets that fit their head geometry. Improved fit could be achieved by customising the inner liner rather than the whole helmet, thus saving time and money for the consumer, and minimising the legal issues associated with safety standards.

The process from the beginning to the end comprised of five steps:

1. Capturing geometric data with a 3D body scanner
2. Capturing non-geometric data in the form of a pressure map
3. Designing the inner liner
4. Developing the manufacturing process for the inner liner
5. Manufacturing the inner liner

Current rapid manufacturing technologies cannot yet produce low-density polyurethane foam, which is the normal material for the inner liner. To overcome this problem, the material and its properties had to be mimicked by using laser sintering and future PPP manufacturing technologies developed by project partner De Montfort University, based in Leicester, UK, in combination with lattice-like internal structures.

More than 30 different structures have been designed using the PowerSHAPE design software as potential templates for the liners. The most promising is a honeycomb structure, which is a good compromise in mimicking the polyurethane foam and in being cost-effective for design and manufacturing. STL files based on this template can be generated by the software for used in the rapid-manufacturing machines.

Five customised helmets were produced for five professional test riders. The initial feedback from these riders was that the customised helmets ‘feel good’ and fit comfortably to their shape. The manufacturer, Mavet, also assessed the results positively.

The next step was to run long-ride tests with the new helmets, to confirm the improvement in comfort perceived by the riders. Objective measurements also were undertaken by using pressure sensors to measure the actual pressure exerted by the helmet on the head. This was done for one rider and the pressure distribution was found to be significantly improved.

For further information on the Custom-Fit project, please go to www.custom-fit.org