Aerospace research accelerated by laser vibration testing

Reducing Permanent Load for Increased Lifetime

Failure is not an option – particularly in commercial aviation. In this industry, electronic components, printed circuit boards and sensors are exposed to continuous vibration loads. Testing printed circuit boards and structural elements in a way that simulates vibration and impact loads ensures continuous operating reliability. The non-contact vibration sensors from Polytec are ideal for dealing with this problem. The high-sensitivity laser technology reliably detects vibration-related weak points on printed circuit boards or individual components, right down to individual bond wires. Modal tests and order analyses quickly provide you with the right data for component, PCB, enclosure and attachment optimization.

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A Practical Example:

Polytec Scanning Vibrometers allow you to take the printed circuit board’s vibration modes into consideration at the layout stage. This means that heavy components such as capacitors, or processors with cooling elements, can easily be positioned in the deflection shape nodes. Continuous loading can be reduced by 80% as a result of this and the service life can be increased accordingly. Visualization by Polytec is a critical resource for this.

Preparing CAE Data Overnight

Lightweight construction is the guiding principle in aerospace development. Adapted materials such as fiber composites must be used if aircraft are to reach their destinations. Experimental modal tests are vital for reliably validating finite element simulations. Automated individual tests are a time-saving solution for implementing an efficient bottom-up approach – in other words, for validating component models prior to a final GVT (ground vibration test).

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A Practical Example:

You can even capture valuable data by performing measurements on scaled models in the wind tunnel. Doing so allows you to visually and remotely record flutter and other undesirable properties without influencing the flow. The optical vibration sensors provide you with an integrated concept for using CAE data to prepare tests. This measuring technology fits into the CAE world smoothly, since the sensor is a software-controlled laser beam. Automated solutions such as RoboVib® provide your simulation department with the data it needs to conduct validation operations – even overnight.

Non-destructive testing using lamb waves with high spatial resolution

Lamb wave tests are an adequate method for analyzing light-weight structures like carbon fiber-reinforced plastic (CFRP) used for the aviation industry. When it comes to fiber-reinforced composites, it is extremely important that damage such as delamination or cracks are detected and localized in good time – both in production and during operation. “Lamb waves” – surface waves that propagate on thin plate structures – play a major role in non-destructive materials testing, since they interact with different types of material faults, which makes damages visible.

Polytec Scanning Vibrometers are suitable for designing component-integrated sensor networks, which are increasingly being used in critical structural elements, including aircraft, so as to continually monitor them during operation (structural health monitoring).

Scanning Vibrometers from Polytec have established themselves the world over as development tools for adapted materials testing methods. The non-contact systems visualize the temporal propagation of Lamb waves with a high spatial resolution. The entire 3D vibration vector is recorded for each scan point, so that the typical S and A waves are broken up during the analysis. Laser vibrometers are thus indispensable for you as tools for researching Lamb waves and developing methods that are suitable for industrial purposes.

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Example for lamb wave testing:

Integrated sensor networks should simplify structural health monitoring of modern aircraft structures and actively indicate incipient damage. The quantitative and temporal propagation of test signals in the component can easily be checked and visualized with laser Doppler scanning vibrometers, allowing for reliable calibration of experimental sensor networks and proving dependability. Read more about structural health monitoring using lamb wave testing in the application note below.

Ready for Take-Off and Measurement Operations

Light penetrates in a vacuum – and light is the tool of choice if you want to test components for space. Satellites, satellite experiments and satellite instruments experience maximum stress during take-off. The eigen frequencies of all the components need to be coordinated if extremely quiet design is to be achieved, if independently unfolding structures such as solar sails or antennae are to be created and if the lack of external attenuation is to be overcome.

Experimental modal tests carried out using laser vibrometry precisely determine these properties – even in vacuum chambers and on the most sensitive surfaces under cleanroom conditions, at maximum temperatures or under cryogenic conditions. Their high dynamic range enables measurements both under take-off conditions and when micro-vibrations are simulated.

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A Practical Example:

Solar sails save fuel during scientific space missions, thereby extending the length of the mission. NASA uses Scanning Vibrometers from Polytec in pressure vessels for 1:1 model analyses to effectively predict resonance points.