Thales Technical Unit Control and Display Systems (CDS) uses electromagnetic compatibility (EMC) simulation to reduce testing costs on each new cockpit instrument.

Thales Technical Unit Control and Display Systems (CDS) uses electromagnetic compatibility (EMC) simulation to reduce testing costs on each new cockpit instrument. EMC is a major design challenge in cockpit instruments because they have a clear face which makes them difficult to shield. FLO/EMC electromagnetic simulation software from Flomerics enables Thales engineers to evaluate its products' radiated emissions and susceptibility during the early design stages.

'We use FLO/EMC to identify and fix EMC problems prior to the prototype stage, usually by improving the shielding,' said Julien Blanc, EMC Specialist for Thales CDS.

'As a result, this eliminates the need for late-stage design changes which in turn saves money by avoiding the need for modification of prototypes and additional testing.' Thales is a leading international electronics and systems group that employs 60,000 people in 50 countries.

Thales makes a wide range of cockpit and display systems for military and commercial aircraft.

EMC is usually a major concern in the design of these systems.

For example, engineers need to ensure that emissions from the display do not interfere with radio communications or radar-based collision detection systems.

In the past, these concerns were addressed by building prototypes and testing them for EMC compliance.

This often required expensive fixes on the existing design.

In any case, the prototype had to be modified or re-built from scratch and the testing process had to be repeated.

This was expensive and in some cases had an impact on the product launch date.

To improve the design process, Thales evaluated several different electromagnetic simulation methods.

'We evaluated the major calculation methods and the leading software packages,' Blanc said.

'We selected FLO/EMC because its predictions consistently matched our physical testing results and it is easy to use.' For example, in a recent experimental study, FLO/EMC predicted that radiated emissions at 160 MHz would be 33dBuV/m in the far field and 95dBuV in the near field.

Actual measurements were 35dBuV/m in the far field and 92dBuV in the near field.

FLO/EMC uses the Transmission Line Matrix (TLM) method for solving Maxwell's equations, which solves for all frequencies of interest in a single calculation and therefore captures the full broadband response of the system in one simulation cycle.

In a recent application, calculated resonant frequencies for a cockpit instrument perfectly matched the test results for the same polarization.

This insight quickly led to the design change of putting conductive material on vertical slits in the side cover of the cockpit instrument.

Re-running the simulation showed that this solved the problem.

The result was that the very first prototype met EMC specifications.

'We have used FLO/EMC to simulate seven recent products and in each case we have found and fixed EMC problems in the qualification stage,' Blanc said.

'Fixing problems in the early stages of the project is much less expensive because it avoids the need for building and testing additional prototypes to evaluate potential fixes.'

Intertronics will be showing how to solve adhesives problems at the Southern Manufacturing Show at Thorpe Park.

If you specify or use adhesives then you really need to meet the adhere people at Intertronics - and the Southern Manufacturing Show at Thorpe Park on February 7th and 8th is a great place to do just that. New products from Intertronics include low cost robotic dispensing and single process mixing/degassing equipment. The IandJ7100 bench top Cartesian dispensing robot is an ideal choice when cost and bench space are important considerations.

With prices starting at circa GBP4K this brings robotic dispensing within reach of small assembly shops, specialist manufacturers and dedicated project cells within larger companies - ideal for subcon production.

It will be of interest to producers of all kinds from instrumentation, electronics, sound systems to decorative and display industries where flexibility and cost are vital factors.

The IandJ7100 handles a dispensing area of 200mm x 150mm and is capable of storing up to 100 different programs, but takes up less than 1/2 metre on the bench.

It is ideal for dispensing adhesives, coatings, gaskets, potting, filling and shielding materials to a resolution of 0.02mm.

The IandJ7100 offers 3 axis continuous path or point to point operation using dots, lines, arcs and circles, with full step and repeat copy functions and automatic offset calculations.

Implementation is simple, as is 24/7 operation with 'quick fluid' purge function and 100 program capacity - each with up to 4000 points.

Mixing and degassing of materials such as precious metal pastes, pharmaceuticals or optical adhesives is generally a two-part process taking a very significant amount of time, especially when product pot life can be measured in minutes - Intertronics have changed all that with the introduction of their Thinky ARE-250.

This patented benchtop planetary mixer is proven in Japan and the US with many thousands installed in laboratories and electronics manufacturing facilities.

The Thinky technology is now available CE marked - says Peter Swanson, MD at Intertronics - 'the ARE-250 mixes, disperses and degasses down to micron level without a vacuum and in the customer's own pot.

It is ideal for expensive material mixes such as filled epoxies for die attach and for materials of variable viscosities.' Indeed, the ARE-250 may be used to formulate and mix adhesives, sealants, molding compounds, lubricants, slurries, coatings, inks, paints, abrasives, bio chemicals, cements, medical compounds, cosmetics/personal care materials, detergents, conductive pastes, dental materials, foods, construction materials or any other materials which are hard-to-mix, hard-to-degass, or hard-to-wet.

Typical applications include epoxies and polyurethanes, especially where optical clarity or thermal conductivity must be maintained (by eliminating bubbles).

The benefits of the ARE-250 can especially be seen in time critical situations such as two-part polyurethane with an isocyarate component and a pot life of around 10 minutes - single process mix and degassing relieves the pressure on the operative and the process by ensuring the adhesive is workable for maximum possible time.

The whole mixing/degassing can be done in a much reduced time frame of seconds to minutes dependant on materials.

ARE-250 also mixes gold leaf particles, glass micro-spheres, aluminium oxides and nano-particles and provides 5 program memories, each with 5 process profiles available.

These are operator determined and programmed in for instant access.

It is found for example that some materials benefit from multiple mixing/degassing/mixing/degassing cycles with different timing and spin speeds at each stage.