Vibration-related failures in aerospace involve satellites, launch vehicles, and aircraft components that are expensive to replace. While traditional vibration testing can overcompensate and damage parts, modal analysis performs tests on the product before physically examining its endurance. Using modal analysis creates smarter vibration tests by measuring the structure’s inherent properties rather than just testing its durability.

Limits of traditional vibration testing

Traditional vibration testing in aerospace has several limitations due to its “brute force” approach. Other issues, like stress, intense pressure, and frequent miscommunication with aircraft maintenance staff also play a factor. However,  tests are still flawed. The following are some common limitations of traditional vibration testing.

Overtesting

Using traditional vibration tests, engineers risk overtesting the product. They simply measure a component’s durability by increasing the vibrations and assessing how it withstands. If engineers overdo it, they may make unnecessary changes or cause damage to the component, leading to costly repairs.

Inefficiency

Additionally, traditional vibration tests are time-consuming and expensive because they continuously increase the vibrations until the component proves stable or fails. The process doesn’t alert engineers to the potential issues with the design, so they might tweak the wrong thing and cause more failed tests.

Lack of predictability

Traditional vibration tests don’t make predictions about the design’s integrity before the actual test. Engineers can’t identify the root cause of the issue or predict how the changes will affect it, leading to more expenses and wasted time.

Modal analysis is smarter

Modal analysis provides a more effective solution to these vibration testing issues. It focuses on understanding the issue instead of merely testing durability. The process identifies a structure’s natural frequencies, damping, and mode shapes, similar to how a guitar string vibrates at different pitches.

With modal analysis, engineers can use the component’s inherent properties to design highly targeted and realistic vibration tests. Engineers focus on testing the most vulnerable parts of an element using the specific frequencies they measured during modal analysis. Advanced solutions, like the SignalCalc900 Series Software from Data Physics, help run the advanced simulated tests, review results, and generate reports.

Benefits of modal analysis in aerospace

The aerospace industry has high stakes, so using modal analysis to enhance testing and make components stronger is ideal. The following are key benefits of using modal analysis in vibration testing.

Enhanced reliability and safety

Because modal analysis enhances the testing process, it improves the reliability and safety of components and aerospace crews. Detailed tests prevent in-flight failures and improve the integrity of the aircraft.

Accelerated development

Modal analysis reduces the time required to develop new components by evaluating products before construction, enabling engineers to make necessary adjustments. Virtual testing and simulations reduce testing cycles, leading to quicker product development and implementation. Analyzing vibrations limits maintenance costs and downtime because engineers optimize their designs before building expensive prototypes.

Lightweight structures

Weight is crucial in the aerospace industry, and modal analysis enables engineers to confidently remove unnecessary mass. Engineers can predict the vibrational integrity of the machine without a particular part and determine if it makes structural sense to remove it. They can then make more-informed decisions to reduce the machine’s overall weight. Data Physics offers training packages to help engineers optimize their use of vibration testing products and modal analysis.

Tools and techniques of modal analysis

To use modal analysis effectively, engineers should employ various tools and techniques. Modal analysis requires two key components—data acquisition systems and sensors. These machines adequately perform modal analysis using their specialized software to process data and visualize mode shapes.

Data Physics helps companies with many noise and vibration testing challenges. It offers comprehensive testing items, including shaker systems, expert applications support and service, power amplifiers, dynamic signal analyzers, software, and vibration controllers. Consider working with this leading provider of vibration testing solutions for aerospace components.

Challenges when implementing modal analysis 

Engineers make mistakes when setting up modal tests due to their nuanced approach. One challenge is incorrectly placing sensors, which provides inaccurate data. Another problem is when engineers misinterpret the data. A possible solution is to use AI when interpreting data to limit human error. The test is only as good as its boundary conditions, so making poor assumptions when constructing the modal test can provide skewed results.

Model correlation is another challenging step. Computer models, like finite element analysis, must match real-world test data from modal analysis. Inaccuracies can create insufficient data that fail to consider fundamental factors. The approach must change when transitioning from a single component to a complete aircraft system. Incorrectly calculating the modal analysis of an entire system can lead to future failures.

Shift to data-driven designs 

The aerospace industry is transitioning from “brute force” testing to intelligent, data-driven designs through modal analysis. Aerospace engineering is becoming more modern, reliable, and efficient by moving beyond simple testing and focusing on a component’s foundation. Working with Data Physics helps you make this shift.