View from the top: More reliance on virtual prototypes

<b>According to Dr Cris Emson, CEO, Infolytica Europe, computer simulation has only relatively recently matured as a 'must have' tool for designers.</B>

While the speed of modern computers has allowed much more sophisticated virtual design tools to be created, the real maturity point was when full 3D simulation became common place on an inexpensive desktop PC. But can it ever fully replace physical prototyping? "In most cases I would say not," said Dr Emson. "There are some exceptions such as large magnets. For example the magnets for the CERN particle accelerators, you would not expect them to be building and testing a series of prototypes in that case. For more everyday applications it would be quite usual to use virtual prototyping tools to refine the design to what is hoped is the end product, but then build a physical prototype for final testing and confirmation. What we do find however is that much more reliance is made of virtual prototyping tools than before. Engineers are willing to accept that modern simulation software really is very accurate indeed, or at least as accurate as the data being put in. What I mean by this is that both the physical size and shape as well as the material properties are always variable in nature (due to manufacturing tolerances)." Where simulation tools become very effective is to establish how sensitive a design is to the various geometric parameters and material properties. Ideally a design is generated such that any variations in size and material properties do not cause the device to fail performance checks. These kinds of simulations are easy using the virtual design tools, basically a 'what-if' type analysis, and would be practically impossible to do in a consistent way using physical prototypes. But progress continues and part of that is down to the hardware available. Dr Emson said: "Now that the speed of PCs has tended to stabilise, the biggest change in the hardware is the increase in number of Processors available. Software is adapting to utilise this new type of hardware, but it is probably fair to say that rather than make the software run a lot faster, the use of multiple processors instead can be better used by allowing multiple simulations to run in parallel. This is ideal if trying out multiple solutions with varying parameters as mentioned earlier." And the software tools themselves are changing in some cases by including a lot more 'knowledge'. Dr Emson takes the example of the motor design software tool MotorSolve. "It can perform initial 'sizing' by taking the basic specifications (supply voltage, required torque, size constraints) and having chosen a suitable template for the rotor and stator the software then adjusts the various dimensions to give a first iteration of the motor design. The designer can then apply their expertise to further refine the motor to obtain the optimal performance satisfying the initial specifications. This has completely changed the way design software works – rather than build a model and then run a simulation to extract the motor performance, we are instead starting with the desired performance and allowing the design tool to come up with an initial design. "Added to that the software also includes the effect of various cooling strategies, all within a single, simple to use package – so you can see the nature of design software is definitely changing, making it accessible to design engineers who need to get the job done quickly, without wanting to learn the intricacies of complex software."