Lecture Autodesk inventor Parametric modeling An introduction

In this chapter, students will be able to understand Create simple extruded solid models, understand the basic parametric modeling procedure, create 2D sketches, understand the “shape before size” design approach, use the dynamic viewing commands, create and edit parametric dimensions.

Parametric Modeling

An Introduction

Parametric Modeling

Feature-based modeling

Constraint-based modeling

Also called:

Parametric Modeling uses parametric

constraints to define and easily modify

part features, and to create relationships

between these features in order to create intelligent part models These virtual parts can then be combined to form assembly

Basic unit of a parametric solid model

A feature is a 3D shape Parts are

formed by their features

Model features mimic actual design & manufacturing features (e.g., fillet,

counterbore hole, draft angle)

2 basic kinds of model features:

A parameter is a named quantity whose value can be changed

Parametric dimensions:

changes

parts, assemblies

A constraint is a mathematical

requirement placed on the geometry of

a 3D model

Kinds of part constraints:

parallelism tangency, colinearity)

Assembly constraints (e.g mate, insert)

Parametric Modeling Characteristics

Model flexibility; easy to update, modify

function of a feature)

to CSG)

Drawings generated from parametric model

Relationships between parts are maintained in

Top–Down: Product Development

Product

 Assembly

 Sub-assembly

 Part

 Feature

Bottom-up: Part Modeling

 Some geometric constraints added automatically

built-in) features

Rough sketch

constraints are

automatically applied

Geometric Constraints

Can display

constraints

Apply

additional

constraints

Dimensional Constraints

Add Dimensions

Feature Generation - Extrude

Built-in Features

Feature Tree

Parametric Modeling

Nada Mas

An Introduction