In a remote spot in the heart of the Bedfordshire countryside, a group of engineers regularly don dark glasses, ensconce themselves in a darkened room and settle down to watch crude flickering images projected on a wide screen.
These design review meetings of plant engineers, designers and suppliers at Nissan’s European Technology Centre at Cranfield, Bedfordshire are an essential ingredient in the development of the replacement for the Almera, due to come off the production line at Nissan’s Sunderland plant in 2000.
Nissan, along with other volume car makers, is rapidly embracing virtual reality technology to cut time and costs. Although Nissan has used VR before, during development of the Primera Estate, this time it is being used from the start for the new car.
Land Rover trod a similar path while developing its production lines for the Freelander and Rover has said it will adopt a VR approach on all future models.
The virtual factory is the logical next step in the evolution of cad-cam using models of components to simulate not just the car but the whole production line before any parts are made and plant is installed on the factory floor.
The obvious advantage is that components can be redesigned quickly, or the flow of the production line altered in a fraction of the time and cost of traditional methods.
The VR factory uses virtual robots and workers generated by Israel-based firm Tecnomatix’s CAPE tool set.
Nissan’s CAE system utilises Ideas Master Series software from SDRC, but the Tecnomatix tool can handle data from most Cad systems used by outside suppliers. This information is then used to create the VR simulation.
Nissan’s plant engineers normally Sunderland-based, but who spend about six months at the NETC working on each new project use VR to experiment with different ways of arranging the machinery and sequence of the production line.
The virtual factory is used to confirm that robots have enough room to move, or to ensure that production tools fit correctly. It can determine that complicated components, such as airbag modules, assemble correctly, and can also be disassembled easily for repair and maintenance. It can also assess line speed to accurately estimate production capacities.
By using virtual people to simulate manufacturing staff, plant engineers can also take measures to lessen health and safety risks such as repetitive strain injury, excessive bending and the potential hazards of dangerous obstructions and moving machinery.
By working alongside the designers, production engineers can begin to write method sheets for each assembly operation and start operator training, all before the line is installed.
The car manufacturers’ enthusiasm for VR is driven by economics they have to reduce development lead times and cut costs to keep up with market tastes and maintain margins.
According to Andy Palmer, Nissan’s general manager for vehicle design and testing, traditionally up to 25% of development time was lost on assembly problems and 15% through component failures.
Prototypes were built by hand before any testing could take place and production sequences could be assessed only on full-scale factory mock-ups.
The use of VR can eliminate 80% of those time losses and tests can be carried out for a fraction of the cost in a fraction of the time, says Palmer.
Nissan reduced development time for the Primera to 31 months, but says the vehicles it is working on now will take just 25 months. The ultimate target is to get from styling to production in 12 months.
The virtual factory technology is clearly not mature yet, but developments are moving so fast that Nissan, and other manufacturers, are already looking further ahead. Hologram technology is likely to be the next area for development.