We need to talk about mobile phone design
Buyers of mobile phones have an insatiable appetite for novelty. It is a characteristic shared across the whole of consumer electronics – one need only to look at the production cycle of tablet computers for example. The time for producing an upgrade for a given mobile phone can now be as little as three months, while consumers expect a step change in technology in as little as a year to 15 months.
Such timing pressures place enormous demands on the designers of consumer electronics, so the major manufacturers are becoming more and more reliant on design and simulation software to help them bring new products to market faster. Jeff Brennan, of Altair Hyperworks, noted that use of simulation software is growing rapidly across all industrial sectors, with an average increase in sales of about 15 per cent last year – but in electronics simulation, software sales rose about 30 per cent.
According to Manuel Rei of Dassault Systèmes, the shorter lead-times from software modelling can be dramatic: ‘A job that was done within a week is now done within half a day.’ But, whether it be a tablet computer or a mobile phone, electronic and mechanical modelling and optimisation are involved, so it is vital that the different software packages used for different specialised parts of the design process are able to communicate with each other quickly and effortlessly.
Take, for example, a problem such as how to make a mobile phone or tablet computer as small as possible, while packing all the electronic components into the space as densely as possible. The obvious solution is to use a flexible printed circuit board. Traditional rigid printed circuit boards (PCBs) are essentially two dimensional surfaces, which limits the designers’ ability to pack everything into the small space available.
Flexible PCBs on the other hand are inherently three-dimensional – the flexibility of the board allows the designer to place different parts into different places in space. Rei explained: ‘When you take any mobile phone, any digital camera, any DVD or mp3 player, or any notebook, you have more and more flexible circuit boards – you don’t have the rigid boards that you saw in the past.’ The manufacturers of such equipment can benefit from this capability. ‘Over the past 10 years, the software industry has provided many improvements. For flexible printed circuit boards, we were able to divide by five the time needed to model and engineer a flexible board,’ Rei added.
The ability to model the circuit board in three dimensions makes the mechanical designers’ lives easier. But, he noted, ‘The concern comes with electronic CAD, where the layout of the electronic circuits is done in two dimensions.’ Dassault Systèmes’ software can offer a way to ‘flatten’ the 3D mechanical design to give a two-dimensional board to the electronic designer. The interchange does not end there: ‘When the electronic designer sends back the final design of the board, the mechanical designer needs to reposition it into 3D space and this is where software plays an important role,’ he added.
Increasing numbers of simulations are being performed on 3D data, Rei said. Manufacturers want to perform simulations on the product as a whole, not just on the board, and this means they need a 3D model displaying the board and also all the other components that make up the product. This plays to Altair’s strengths, according to Brennan: ‘We exist as a common tool to link the CAD with all types of physics-based simulation, so companies use our products, including one in particular called Hypermesh, to take their design configurations and build physics-based models from them. These models could go to any number of simulation solvers – the thermal problems, packaging, basic stress, survivability, for example – and drop tests are a huge thing these days.’ Optimisation is particularly important, he continued: ‘Putting those simulation algorithms into a loop to improve the design, or provide information to the designers on how to make improvements. Should they change the thicknesses of these parts; should they be positioned in a different place; should they make different connections; should they use different materials?’
Altair’s software can eliminate a lot of repetitive manual tasks at this stage, Brennan stressed: ‘A company that is trying to gather and idealise data – how do they assemble and mesh and add boundary constraints? That can be automated with our software. Dealing with data and assembling models for simulation can be one of the longest lead-times in the electronic design process. In years past, it may have taken weeks or months to assemble a mobile phone model and put it through a cycle of drop tests or thermal loading. One of the biggest latencies was just building the model. We have applied our open technologies and automated it – meshed it the way the customer wants. That can take the lead time down for building a valid physics-based simulation model from a month to a day.’
Even something as simple as the copper electrical connectors needs to be modelled and communicated from the electrical to the mechanical designers. Rei cited the example of one customer, a subsidiary of the Swatch Group, that makes the mechanisms for Swatch: ‘They have a watch called the T-touch – part of the Tissot brand. This has a tactile screen and a circular board inside. The board is clamped by the watch housing which is titanium or stainless steel. So the mechanical designers need to know where the coppers are so they can position the clamps at the proper locations. The mechanical designers need to see where the coppers are to avoid any short circuits.’
The key thing, he said, was to have the different engineering teams working in an optimal way, sharing their respective design data and to share updates with other designers. ‘Today, the focus is on streamlining the exchange of information and of design intent between the disciplines. Also today, when we are talking about a company, we are talking about different business units, organisations, locations and time zones. Basically, you can have the electronic team in Japan or the US, the mechanical team in Europe and the software team most likely in India. So you can have different people working together who are not in the same time zone and they need to collaborate. The more you improve this collaboration, the more you will reduce the turnaround time for producing new designs.’
To emphasise the importance of designers talking to each other, Dassault Systèmes now stresses how its software delivers ‘social industry experiences’ to its customers. According to Rei, ‘All Dassault Systèmes experiences are based in our V6 platform, which is a collaborative environment where users will have all our software applications. They can use Catia to do 3D design of the circuit board or they can use SolidWorks – both are integrated with V6, so all the data being created within applications will be managed and traced inside the V6 platform.’ Dassault Systèmes itself does not provide ECAD tools, but relies on the main tools that are available on the market – Cadence, Zuken, or Mentor Graphics, for instance – and it integrates these software packages within the V6 platform. Through this platform, the mechanical designer using, for example Catia, can exchange information with the ECAD designer.
There are further tools, such as Delmia, which communicate downstream with the manufacturing process, but Dassault Systèmes has recently added Exalead which provides search tools and in February of this year, it acquired Netvibes which provides dash-boarding tools, making it easier for engineers to create a dashboard and display the data they believe are relevant to their job. ‘We would like to connect the dots within and outside the company,’ said Rei.
In an analogous way, it is the breadth of the range of applications and expertise in Altair’s physics-based simulation that appeals to the electronics industry, according to Brennan: ‘Companies outside of auto and aero are beginning to embrace simulation, not just to replace testing, but to go beyond that and lead the design process. We have provided this same level of integration within the software tools for all other industries, including the automotive sector.
‘When you consider the design of an automobile – as a complicated assembly of parts each of which has to be meshed and analysed and then tested, as a system, for vibration, crash, and vehicle safety – it’s not that dissimilar if you think of a mobile phone: there are lots of small parts welded together in a big or small box and they need to survive all kinds of thermal and structural loading. We don’t force our customers in electronics to use our process from start to finish, though we hope they do. We have grown up with a focus on open architecture and interoperability with other technologies in this space,’ he concluded.