Engineering the sound and silence of quality

MSC Software

MSC Software

Guest post by Ze Zhou

Sound is quality.

If a product is supposed to be silent but isn’t, it’s lower quality. If it’s silent when it’s supposed to make a noise, it’s lower quality.

The solid “thunk” of a car door and the silence inside the car are both expressions of quality. The distinctive tick of a high-end wristwatch is quality. The refrigerator that makes just enough of a low hum to prove that it’s working is quality.

Sound has been a factor in product quality for decades, if not centuries. However, factors are conspiring to change the fundamentals of creating a fitting sound profile for a product. Consumer preferences and government mandates are making energy efficiency and environmental sustainability higher priorities. They require new designs and new materials, such as carbon fiber composites, that can alter a product’s sound profile.

New materials and designs are challenging for engineers. With no accumulated knowledge to rely on, they cannot make credible predictions about a new material’s acoustic performance before the design goes to prototyping and production.

As we wrote in a previous blog post on Elevating Sound, the automotive and aerospace industries are compensating by integrating acoustic simulation technology into their design processes. Airbus, in particular, has successfully “democratized” access to sophisticated acoustic simulation technology by extending it beyond analysts to front-line design engineers. The company has implemented high-end acoustic simulation software on its network that enables engineers to submit calculations then receive answers via an in-house developed automation platform.

Airbus, of course, also has something in the range of 10,000 engineers who design one aircraft at a time. How can an appliance company with 100 engineers designing 10 products at once follow its example?

A lot more easily than you might think.

Aerospace and automotive companies have more resources, but many of those resources are consumed by their products’ greater size and complexity, not to mention the regulatory requirements they have to meet. They have to infuse acoustic simulation technology into every facet of their design processes because any change to a design at any point in the development process can have huge consequences.

For example, if engineers add mass to an aircraft design, it affects the whole product’s fuel economy. The company needs acoustic simulation everywhere in their design process because it needs to know long before prototyping and production what effect the sound-related modification has on the final design.

By comparison, the appliance company may only have 100 engineers, but it also doesn’t have to evaluate every single change as exhaustively as Airbus does. Dishwashers and refrigerators aren’t as complex as aircraft. Not as much rides on each design change. Where the aerospace engineers need as much certainty as possible, the appliance company’s engineers may only have to be able to make credible estimates of how design changes will affect their product’s performance and sound profile.

So rather than investing in a top-to-bottom acoustic simulation program, the appliance company could take one of several lower-cost but still effective measures.

The first and most obvious solution is outsourcing, which is as simple as sending computer-aided design (CAD) models to an analyst firm and receiving results back. This approach would keep overhead expenses manageable for a company that doesn’t often make substantial changes to its products but wants to maintain their sound profiles. They might only need occasional acoustic simulation to verify their sound profile.

Companies that re-design more often and more extensively, or who don’t want proprietary design data outside their own walls, need an in-house solution that won’t break the bank.

One option is to contract with an outside analyst to create acoustic models of each product according to the company’s design best practices. Engineers can use the models as benchmarks to estimate the effects of new materials and designs on the products’ sound profiles.

Some companies need a more interactive system that enables engineers to run simulations. These companies can purchase a single license of an acoustic simulation solution, train one or two engineers to use it, then use them as an in-house service bureau to support the rest of the engineering staff.

Whatever solution a company chooses, the underlying point is that with the advent of new materials and design imperatives, most manufacturing companies need some form of acoustic simulation to maintain their products’ sound profiles. A consumer product probably won’t fail because of a flawed sound profile, but it will definitely be at a disadvantage against competitors with well-crafted sound profiles.

Manufacturers need to know in advance whether the shutter click of the digital SLR camera sounds enough like a mechanical SLR to satisfy serious photographers. They need to know the dishwasher is quiet enough to run at night without waking up the customer’s kids, or that the cap of the rollerball pen makes a satisfying “click” to justify its $300 price tag.

Integrating acoustic simulation technology into their design processes provides manufacturers with that insight. They don’t need the resources of a multinational aerospace company to do it. They just need to know their options.

Ze Zhou is a senior application engineer and product marketing manager at Free Field Technologies, an MSC Software company.

Quiet Cars - An Introductory Guide to a Quieter Ride (eBook and online community)