# Parametric Model

FEM-Design provides a module for workflows and projects where the geometry of the structures are similar but differ mainly in their major parameters and dimensions. The *Parametric Model* module delivers solutions for quickly entering and modifying typical structures.

So, *Parametric Model* is an editor module, where you can create parameterized models as templates for later use in FEM-Design* 3D Structure *module.

Contents:

## Access

Click the *Parametric Model *command button on FEM-Design startup dialogue.

## The scope

The following structural and load objects can be applied for building-up parameterized structural frame-, shell- or complex-systems:

## Parameterizing tools

The *Parameter *tab gives the tools for setting up variable parameters (numbers and geometric parameters) and for assigning them to the modeling objects:

### Base rays and planes

*Base rays* and *Base planes* can be used as the frame structure of a parametric model. Structural analytical objects and loads can be attached to them.

An example for defining *Base planes* and *Base rays*:

- The
*Base planes*define the planes where- the
*Point supports*and the*Columns*will be placed, - the bottom and the top level, and the first and last plane of the roof structure will be.

- the
- The
*Base rays*define the axis x’ direction of the*Beams*(and for locking, see later*Locks*).

### Grids

*Grids *are used to create iterative patterns like a series of columns or an array of point foundations.

With *Grid *we can create 1D (line), 2D (planar) or 3D grids and meshes:

Structural and load objects can be attached to a *Grid *(system). The attachable objects should fit in one cell of the *Grid; w*e* *can place an object anywhere in a cell, and it will be attached to its host *Grid*.

*Grid *can be warped in every possible way by its corner points.

By directions, we can set the number of *Grid *cells by giving numbers (e.g. 2) or Integer-type parameters, and set where we want to multiply objects within the *Grid.*

We can also set that the *local y’ axis *of the grid-assigned object should follow the grid direction and position changes or should keep its original direction.

### Locks

Locks are used to bound nodes of objects, base lines and *Grids *to the intersections of *Base objects*. If the *Base objects* move, the locked objects are moving with them. The locked objects are marked with the lock symbol in the model space.

Intersections can be defined by two base lines, a base line and base plane, or three base planes. The following figure shows an example of how to lock the endpoint of an inner *Beam *to the intersection of *Base plane* and *Base ray*.

### Constraints

With *Constraints *we can define fixed numerical or parametric distances between parallel *Base objects*.

The following figure shows an example of named parametric *Constraints *defined as distances between *Basic planes*.

### Parameters

With *Parameter *we can control the parametric model, and later - in *3D Structure* module - we can set the final structure with their values. A new parameter (integer or real) can be defined in the dialogue of *Parameter *tool or during *Grid *and *Constraint *creation.

If one of the parameters (which are assigned to the parametric model) change, the modifications will be automatically applied to the parametric model.

Example 1

Example 2

Example 3

## Insert parametric model to 3D Structure projects

We can insert a parametric model (saved to file with name and *.prm* extension) in our currently open 3D Structure project with the following commands:

*Tools*>*Apply parametric model...**Edit*>*Paste file...*

After opening a *.prm* file, we can finalize the values of the available parameters in an upcoming the dialogue, and place the fixed size model in the model space.

**Parent topic**: Import / Export Model