Vibration Testing Types

Types of Vibration Testing Offered by WNA

Dynamic Vibration

Dynamic vibration testing analysis a product's ability to withstand the stress that can occur during normal and adverse operating conditions. This type of testing is common in industrial, aerospace, commercial, and military applications. 

Random Vibration

• Random vibration testing excites all of the frequencies within a defined spectrum. The motion is non-deterministic meaning that the futuristic outcome cannot be precisely predicted, but tests the character of the excitation. These are vibrations that are found in everyday life scenarios that are not predictable or repetitive (ex. airplane wing in turbulent airflow). This type of vibration testing is more realistic compared to sine vibration. The goal of this vibration test is to check the durability of the DUT and test if the DUT will fail or function properly under extreme conditions during its lifecycle. 

Sinusoidal—(Sine) Vibration

• Sine is the simplest vibration testing procedure, focusing on a single frequency at any one time. Sine testing is primarily used to determine damage to structures or resonant conditions. 

Learn more about when to use sine or random vibration testing here.

Mixed Mode

• Mixed mode vibration testing is not as common as random and sinusoidal vibration testing, but is a combination of both simultaneously to simulate where both modes are present. While it is not as common as random and sinusoidal, mixed Mode vibration testing better simulates real-world environments than the two vibrations separately. The mixed-mode has several testing types, including:
  • Sine on Random (SOR)
  • Random on Random
  • Sine and Random on Random

Transportation and Packaging

• Transportation and Packaging vibration tests aim to mimic the sorts of vibrations that packages experience during handling, shipment, and transportation. Vibrations that are too severe can harm packages causing them to lose their integrity. As a result, these tests seek to determine if the packaging can keep items secure when jostled around, for instance in a truck during transit, or if it will tear apart at the seams. 

Gunshot

• Gunshot vibration testing is used to determine if the material can structurally and functionally withstand the infrequent, short-duration transient environments shock. This method determines the material's ability to maintain its structural integrity and functionality in “gunfire schedule” environments. Gunfire schedule refers to the number of rounds fired, firing events, and the firing rate.

Combined Vibration/ Temperature/ Humidity

• A combination vibration test is vibrations with the temperature or temperature cycles and humidity simultaneously. This test is mainly utilized in the automotive industry because automotive electronics are subject to high temperatures and heavy shocks during drives.

Shock Vibration

Shock vibration testing simulates the different types of impacts that products may experience, helping predict the hazards that the product may face during transportation. These tests are necessary to duplication and quantify impacts, shocks, and accelerations the load encounters during transfer to avoid shrinkage and reduce costs. For example, when purchasing an iPhone it is expected to survive a certain amount of drops to the ground or if an automotive part can endure carious degrees of challenging forces. Shock vibration testing can produce different pulses to find the peak of accelerations for products, such as:

Pyrotechnics

• Pyrotechnics, also known as pyro shock, the pulse is high frequency, high magnitude pulse shock caused by an explosive event. Pyroshock testing exposes failures to components that are exposed to these high-intensity environments such as aerospace vehicle integrity and defense.

Half Sine

• Half-sine is one of the more common classical pulse shapes. Half-sine shock pulses are created by placing an elastomer, or rubber material, on the surface of impact. The table holding the product is raised to the necessary height to achieve desired acceleration and then is released, stinking the elastomer or rubber surface.

Sawtooth

• The sawtooth pulse falls under the categories of a non-sinusoidal waveform. This wave gets its name from its resemblance to the teeth of a plain-toothed saw with a zero-rake angle. A sawtooth’s pulse comprises both even and odd harmonics, but the sound is harsh and clear. This waveform is best used for the subtractive synthesis of musical sounds, especially for bowed string instruments like violins, because the behavior of a slip-stick bow drives the string to create a sawtooth-like motion. 

Squarewave

• Squarewave pulses are non-sinusoidal where the amplitude alternates a steady frequency and same duration. These pulse waves allow arbitrary durations at both amplitudes, minimum and maximum. The pulse gets its name from the square-like shape the wave produces.

SRS

• Shock response spectrum (SRS) vibration test is a more complex shock pulse that estimates the potential damage of an object. SRS is s set of shock pulses, each with different acceleration values, in a particular frequency range.

Learn how you can receive 20% off of your Vibration Testing at our Test Laboratory.

Standards and Regulations for Vibration Testing

All products are subjected to some degree of vibration in their everyday usage, the majority of organizations and agencies establish vibration testing standards and regulations that industries must comply with. The information provided below shows a quick rundown of some of the most well-known vibration testing standards and regulations:

Contact us if you would like to discuss your shock or vibration test application, or if you have any questions.