Time & Frequency Domain Vibration Fatigue Solution

CAEfatigue is a random response and vibration fatigue solver for the frequency domain plus a fatigue solver for the time domain. It works with mixed random and deterministic loadings or standard time domain based loadings to provide fatigue life and damage predictions, as well as several forms of response statistics. It is exceptionally fast, easy-to-use and capable of handling very large models.
CAEfatigue is used to conduct random response and fatigue evaluations of dynamic mechanical systems in the frequency domain or time domain. The software is available for single input PSD loading with or without deterministic loads like sine-on-random, sine sweeps, sine harmonics, etc.

CAEfatigue also allows complex multi-event, multi-channel PSD loading with cross PSDs and the standard time domain analysis solutions like linear static superposition, the modal participation factor approach or the direct stress recovery approach. It can handle virtually any size model with extreme speed and accuracy.
MSC CAEFatigue Random Vibration Fatigue
Four Powerful Configurations to Choose From

The software is sold in 4 different package configurations:
  • CF FREQUENCY Package, for Frequency Domain Fatigue Analysis,
  • CF RANDOM Package, for Random Vibration only Fatigue Analysis,
  • CF TIME Package, for Time Domain Fatigue Analysis
  • CF PREMIUM Package, for Frequency & Time Domain Fatigue Analysis.
CF FREQUENCY: CAEFatigue Frequency Domain Analysis
CAEfatigue is designed to provide the user with both the random response results and the fatigue results from a structure undergoing loading input from a single random PSD with or without additional loading from deterministic inputs and mean offsets. Response outputs includes mean stress, RMS stress or strain, mean stress plus RMS stress or strain, moments, zero crossings, peaks per second and irregularity factor. Fatigue results including damage, life and margin of safety from a single random input.

The loading inputs needed for CF can come from Optistruct, Nastran, Ansys or Abaqus generated from (virtually) any size model. Examples of inputs are simultaneous wide band and narrow band inputs, wide band random and swept sine inputs, wide band random and deterministic inputs, wide band and swept narrow band inputs, swept narrow band or swept sine wave.
CF RANDOM: CAEFatigue Random Vibration Analysis
CAEfatigue is designed to provide the user with both the random response results and the fatigue results from a structure undergoing loading input from a single random PSD with or without additional loading from deterministic inputs and mean offsets. This package allows the User to do Random Analysis only. Response outputs includes mean stress, RMS stress or strain, mean stress plus RMS stress or strain, moments, zero crossings, peaks per second and irregularity factor.

The loading inputs needed for CF can come from Optistruct, Nastran, Ansys or Abaqus generated from (virtually) any size model. Examples of inputs are simultaneous wide band and narrow band inputs, wide band random and swept sine inputs, wide band random and deterministic inputs, wide band and swept narrow band inputs, swept narrow band or swept sine wave.
CF TIME: CAEfatigue Time Domain Analysis
CAEfatigue is designed to provide basic fatigue analysis tools for the linear static superposition approach, the modal participation factor approach and the direct stress recovery method. This TIME package is intended to provide a vast improvement in the analysis process for conventional static superposition analysis, modal participation factor (dynamic transient) analysis and direct stress recovery analysis. The TIME package uses state of the art software development tools and algorithms to deliver a fatigue solver with superior speed and accuracy. Coupling time domain tools with frequency domain tools provides customers with a complete time and frequency domain analysis package that surpasses the performance and accuracy needs of our users.

CAEfatigue provide a Load Scheduler toolset that allows the User to create unique time based loading profiles from a simple deterministic time signal channel to complicated multi-event, multi-channel loading sequences. Existing RPC, CSV, DAC files can be manipulated / augmented and exported as unique loading event sets.
CF PREMIUM: Advanced Fatigue Analysis in Time & Frequency Domains
CF PREMIUM includes the functionality of CF TIME & CF FREQUENCY packages, plus the capability to do so much more, such as Advanced Random Vibration Output, Surrogate Loading and Calculations at Welds.

For many automotive and aerospace systems it is required to calculate both durability and to rule out the possibility of collision of individual components during severe base shake vibration conditions. Advanced frequency domain methods now exist to enable the durability assessment and response to be assessed in the same analysis. With the advanced random analysis output it is possible to output displacement and/or velocity and/or acceleration and/or force RMS levels and Power Spectral Density (PSD) plots for both absolute and relative responses. In addition, a residual sum of the squares (RSS) is calculated to take into account any off axis response. New post processing options allow the relative response from any node to be compared against the actual distance to all nearby nodes in order to check for the probability of collisions (i.e. RATTLE) between adjacent parts. The response maximum is determined using either a ratio of the RMS (e.g. 3.0*rms) from a corresponding level of probability on a Gaussian or Rayleigh distribution, or by using a method which takes into account the number of cycles of response. Advanced Random Analysis output is an excellent addition to predict structural response under complicated loading conditions found in many engineering applications throughout a wide variety of industries.

The specification of loads for durability is a very important topic. Ideally, any loads used in an analysis or in a laboratory based test procedure, should be as close as possible to the Customers use of the product. In practice, the nearest scenario that can be achieved is to measure multi events and multi input loads (with correlation) from prototype vehicles (test tracks) and then replay these in the laboratory or analysis environment. For analysis, this is feasible and is a commonly adopted method although it does not easily deal with the topic of test acceleration. For laboratory based simulation, especially of parts or subsystems, there is a need (usually because of available test equipment) to simplify the loads down to single input load applied one at a time (e.g. X, then Y, then Z), which poses significant challenges. Two common approaches are currently used. First, an enveloping procedure can be applied to the loads where the multiple loads are combined into a single smoothed profile. A classical application of this procedure involves no knowledge of the structural system so there is no assurance that the enveloped loads will cause the same damage values or distribution. Second, is to use the concept of a Fatigue Damage Spectrum (FDS) where a simplified loading is created which does the same damage on a hypothetical 1 DOF system (where the resonance is moved through the loading). Again, this takes no account of the actual structural system or systems. Surrogate Loading provides a NEW approach, which is a variation of the FDS approach but using the actual system properties. The Surrogate Loading tool provides a way to transform a complicated multi-channel, multi-event time history loading into a simplified “SURROGATE LOAD” that will provide a very similar stress and damage output for the system as the complex test time history did.

CAEfatigue has created an industry first! We now provide the ability to conduct a full Spot Weld, Seam Weld and User Defined weld analysis in the Frequency Domain along with the more traditional methods used in the Time Domain. This capability will allow a full automotive vehicle analysis, that includes spot and seam welds, to be conducted with CF in either the Frequency domain or Time domain.

We use cookies to operate this website, improve its usability, personalize your experience, and track visits. By continuing to use this site, you are consenting to the use of cookies.
For more information, please read our
privacy policy.