FEMtools Framework

An Interactive Desktop and Scripting Environment for Engineering Analysis and CAE Process Automation

FEMtools Framework is a multi-functional environment for advanced engineering application development, integration, and automation. The framework includes data interfaces, database management utilities, mesh generation and manipulation tools, parameter and response management, state-of-the-art data visualization, plus a full featured scripting language and API function library.

Optionally, FEMtools Framework includes a standard finite element library and solvers for linear static and normal modes analysis. Extended analysis functionality is available in FEMtools Dynamics. Alternatively, standard external solvers like ABAQUS, ANSYS, MSC.Nastran, NX Nastran, I-DEAS or in-house solvers can easily be integrated and piloted as part of larger analysis processes.

This open and flexible CAE application development platform is used by analysts to integrate their tools, and create vertical applications that meet the specific requirements of an industry. A unique capability of FEMtools Framework is the integration of data resulting from experimental static or dynamic testing.

FEMtools Framework is used by Dynamic Design Solutions for the development of its test-analysis integration tools to validate, update and refine finite element models. Furthermore, a growing number of development partners are working on integrating their existing tools or developing entirely new tools that exploit the framework infrastructure and re-usable components. This is a more efficient approach than developing new applications from the ground-up. Some examples of current development projects by partners are integration of acoustics solvers, modal analysis tools, substructure synthesis, and vibration-based material identification.

 

Key Features

• Convert finite element and test data into a uniform, structured relational database.
• Analyze, visualize, manage and report your engineering simulation and test data.
• Solve for static and dynamic responses using built-in solvers or by piloting standard commercial FEA solvers.
• Use FEMtools Script with hundreds of built-in math and API functions to access all data and create your own functions and programs.
• Add-on modules and customization provided by FEMtools Solutions Partners.
• Documentation available in English and Japanese.

 

Applications

FEMtools Framework is a software-neutral CAE application development tool mainly used for developing tools that exploit hybrid test and analysis databases. It provides the foundation for all FEMtools products and for products developed by independent partners.

As a stand-alone tool, FEMtools Framework can be used as a utility software for:

• Data transformations – normalization, expansion, reduction
• Data translation – Convert FE mesh, FEA results or test data files from one format to another.
• Pre- and post-processing of FEA and test data – mesh generation and viewing.
• CAE process integration and automation – solver-independent, customized analysis processes and user interfaces (GUI).
• Programming vertical applications using FE and/or test data.

 

Benefits

• Faster and more efficient development.
• Integration of separate tools in a single custom vertical application.
• Re-use of standard components like graphics viewers and data translators.
• Customized user interfaces.
• Software-neutral integration with virtually any FEA package.
• Integration with virtually all types of test data .
• Computing and OS platform-independent architecture.
• The programming language and API provide a layer between the database and applications. This reduces the risk of corrupting the database.
• By using a common development platform it becomes easier to develop new functions in collaboration with partners or subcontractors.

 

FEMtools Framework Components

The main FEMtools Framework components consist of:

• Direct data interfaces.
• Database management tools.
• Mesh generation and morphing functions.
• Mesh quality analysis commands.
• Basic finite element analysis.
• Parameter and response management commands.
• Interactive user interface.
• Data visualization tools.
• FEMtools Script programming language.
• FEMtools API function libraries.

 

Direct Data Interfaces

FEMtools Framework is an open program that can be naturally integrated in an existing CAE environment. Two-directional translators are available with the most popular FEA and test database formats (NASTRAN, ANSYS, I-DEAS , ABAQUS, Universal File, … and with other commercial software like MS Excel, and MATLAB. These translators are direct and are integrated with no limitation of FE model size. New interfaces can easily be developed using the FEMtools scripting language.

The ability to communicate with external databases serves several specific purposes, like for example:

• Converting finite element mesh data between different formats.
• Pre- and postprocessing of FEA and test data.
• Interfacing with an experimental database in order to compare FEA data with test data.
• CAE Integration.

 

Database Management

Interface programs import external databases into a relational database of tables. FEMtools Framework provides a number of utilities for interactive definition, editing and transformation of all data in the internal database:

• Database explorer using tree-lists.
• Project database file for archiving and restarts.
• Spreadsheet-style table editing.
• Transformation of coordinate systems.
• Support of local rectangular, cylindrical or spherical coordinate systems.
• Conversion of engineering units.
• FE model reduction (Guyan, IRS,…).
• Modal database normalization, scaling, truncation and expansion (mode mixing, modal coordinates method, dynamic expansion method, SEREP method,…).
• Interactive picking of sets of elements and nodes or automatic creation based on topology, material or geometry.
• Boolean operations on sets.
• Verification of FEA database integrity.
• Conversion between element types.
• Regrouping of elements to reduce the number of different materials and geometry resulting from local model updating or design optimization.

 

Mesh Generation and Morphing

A function library is available to generate surface meshes and volume meshes. Unstructured surface meshes can be generated for generic surface patches that are defined using simple geometry description (vertex, curve, surface). Volume meshes are obtained from 2D meshes with operations like extrusion and revolving.

This FEMtools API function library complements the lattice-based mesh deformation (‘morphing’) and provides the functionality to mesh very complex geometries. It can be used for applications like parametric meshing for shape optimization, meshing design spaces for topology optimization or to implement mesh coarsening and refinement tools

 

Mesh Quality Analysis

Mesh quality analysis tools verify the quality of imported or generated finite element meshes. Quality metrics like aspect ratio, convexity, taper, warp angle and others can be computed on the fly and visualized with color-coded mesh graphics. Results can be further post-processed by computing histograms or sorting mesh quality values. Additional mesh quality metrics can be implemented using the FEMtools Script programming language.

 

Integrated Basic Finite Element Analysis

If the FEMtools database contains the complete FE model description, the user can import externally computed mass and stiffness matrices, static displacement, normal modes, complex modes or operational shapes. Alternatively, the built-in element library and solvers can be used. Piloting external standard solvers like MSC.Nastran and ANSYS is completely automated using driver scripts.

• Internal finite element library (lumped mass, beams, plates, shells, volume elements, damper element).
• Isotropic, orthotropic and anisotropic material models.
• Constraint equations (SPC, MPC, RBE2, RBAR,…).
• Use integrated FEMtools solvers or pilot external standard FEA solvers solvers.
• Linear static and modal stress analysis for 3D elements.
• Real and complex eigenvalue analysis using sparse Lanczos solver.
• Complex modes analysis using Hessenberg modal solver.
• Normal and complex mode analysis using system matrixes reduced to master DOF with back-expansion.
• Support for various types of damping (modal, proportional viscous and structural damping, viscous damper elements, material damping).
• Upgrade path to FEMtools Dynamics for advanced dynamics simulations.

Finite element and solver components can be separately licensed for integration in third party products that address specific needs for various applications and industries. For examples of commercially available third party products  based on FEMtools Framework see developer partners.

 

Parameter and Response Management

FEMtools Framework provides commands and functions for definition of parameters and responses. Parameters are physical element properties that can be used as variables for sensitivity analysis, design optimization or model updating applications. The definition can be based on the existing property cards, for example the common material property of a set of elements. Alternatively, element sets can be defined by filters, graphical picking or Boolean operators. FEMtools manages the property cards and removes the hassle of manually creating new property cards as new element sets are created. 

• Selection of all element material properties, geometrical properties, boundary conditions, lumped masses, and damping factors as parameters.
• Selection of mass, static and dynamic displacements, resonance frequencies, modal displacements, MAC, FRFs, and FRF correlation functions as responses.
• Lower and upper bound constraints.
• Definition of parameter relations

 

Interactive User Interface

FEMtools is operated via a customizable menu interface, the FEMtools command language and FEMtools scripting. The menu interface is most suitable if you are a new or occasional user, if you need to edit tables or display graphics. You can browse through the different menus to get a overview of the features and easily experiment with different commands. The FEMtools command language is for more experienced users who prefer to type commands in the entry field of the console window. This mode is often the fastest way to complete standard procedures, or run your own scripts. Once a procedure becomes more complex, needs to be developed or repeated often with only small changes, using FEMtools scripting language is the most suitable approach.

For report generation, users of the Windows version can take advantage of the Copy and Paste features to transfer text and graphics between FEMtools and other applications like Word or Excel via the Windows Clipboard.

A user often wants to repeat the GUI menu and dialog box actions on another database, or just keep track of all the action required to reach his goal. FEMtools records all actions in a journal file that can then be edited and re-used as a command script.

 

Data Visualization

Data is visualized using interactive 2D and 3D graphics. Functions, tables, scalar and vector results are visualized in curve, matrix and mesh plots. OpenGL graphics offers quality graphic performance that you have come to expect from the newest generation of engineering workstations:

• XY-curves, matrix and mesh visualization.
• Graphical picking of nodes and elements.
• Multiple simultaneous graphics windows.
• Dynamic viewing (rotation, pan and zoom).
• Support for touch-enabled screens (one-finger and two-finger gestures for dynamic viewing).
• OpenGL graphics rendering (shading, lighting, transparency).
• Color-coded and vector-coded displays.
• Animated, side-by-side and overlay plots.
• Export of animated shapes as AVI files.
• Export graphics in Postscript or bitmap files.

Animated shapes can be saved as AVI files (on Windows) or a series of bitmap files (on Unix and Windows). AVI files can be directly imported in presentation or reporting software.

 

FEMtools Script Language

FEMtools Script is the integrated FEMtools programming language that is designed with the needs of the FEA analyst in mind. The language offers many advanced features but is based on a easy to learn standard syntax (Basic).

Menus and toolbars can be customized to provided access to your own functions and commands. FEMtools Script makes FEA scripting easy and fun so you can focus on your solution.

For more information, see FEMtools Script and API.

Features:

• Compiled execution
• Integrated script editor window – FEMtools scripts can be edited and run from an integrated editor window, with color-coding of commands, functions, statements, etc. This facilitates development and debugging of scripts. Scripts can be compiled and run directly from the Script Editor.
• Mathematical programming – Advanced functions for mathematical programming, array operators, complex numbers, sparse matrices, regular expressions, set manipulation,…)
• Functions for integrating with third party tools (interfacing with Matlab & Excel, launching and controlling subprocesses).
• User interface programming (graphical picking, dialog boxes,…)
• Script encoding for protecting intellectual property or ensuring source code integrity.
• OLE automation/ActiveX
• Error checking
• Online documentation – Access to all function documentation from the online FEMtools help feature. Example program code can be pasted directly into your own FEMtools Script program.

 

Support of sparse matrices

Many finite element-based applications involve the use of sparse matrices i.e. banded and sparsely populated matrices. The memory requirements of programs can therefore be seriously reduced by storing only the non-zero elements of these matrices and perform matrix operations directly on the sparse matrix. FEMtools includes the functions to define, delete and work with sparse matrices.

 

Support of regular expressions

To facilitate string and table parsing, several functions like Match, Replace, Search, and Split are available with support for complex regular expressions.

 

Functions for OLE automation

FEMtools Script programmers can take advantage of the power of OLE automation to extend the capabilities of an application on Microsoft Windows platforms. There are many potential applications for using OLE automation servers. Just imagine how you could integrate with, for example, Microsoft Office applications to use Word as a report writer, use PowerPoint to make presentations of you results or use Excel to post-process FEMtools tables as spreadsheets.

You can also extend the math programming functions of FEMtools Script by making use of the extensive library of math and graphics functions that are provided by general purpose programming environments like MATLAB and its many specialized toolboxes. By exploiting the MATLAB object model you can use all MATLAB functions from within FEMtools Script programs.

There is a growing number of  finite element programs that have been rewritten for the Windows operating system and support an object model. Data interfaces between FEMtools and these FEA solvers could be based on OLE automation.

By using OLE automation, you can seamlessly integrate external tools with your FEMtools Script programs without the user knowing that you are actually using for example Microsoft Word or MATLAB. This possibility holds a tremendous potential to increase the power, efficiency, speed and user-friendliness of your applications.

 

FEMtools API Function Libraries

The FEMtools API is a library of functions that can be used from within script programs to access FEA data or test data, re-use built-in solvers and analysis tools, user interface development, and pilot external CAE or test tools.

• 280+ FEMtools API functions for database access, analysis, process control, user interface programming, mesh generation, mesh manipulation, and  licensing.
• Functions for launching and controlling external tools with ActiveX/OLE automation technology under Windows.
• Access to all components available in the different FEMtools modules (e.g. direct data interfaces, graphics, correlation analysis tools, sensitivity analysis,…).

Prerequisites

There are no prerequisites. See Supported Platforms and Requirements.

 

Options

• NASTRAN interface and driver
• ANSYS interface and driver
• ABAQUS interface and driver
• UNIVERSAL FILE interface and driver
• FEMtools Modal Parameter Extractor
• FEMtools Rigid Body Properties Extractor