Assembly Design

Your Design's Digital Twin

What is a 3D Assembly?

An assembly is simply a collection of individual parts that have been arranged in such a way that they represent a finished product. Assemblies have a structure that you can leverage to manage complexity. When your assembly is complete, you should be able to see it and in some cases interact with it.

Assembly Overview

A dedicated workspace for assembly and top-down design of products.

You'll bring parts into an Assembly workspace and apply constraints, create logical groups of parts called Subassemblies, and ultimately result in a finished design.

Assembly Structure

An important aspect of managing complexity is creating a good assembly structure. Individual parts and small collections of parts, called sub-assemblies, are the components of a larger assembly.

Think of a "car" as the assembly. The car has several sub-assemblies, such as "transmission", "chassis", "dash", and each of those sub-assemblies has a bunch of parts that make up the sub-assembly.

Bottom-Up Design

Bottom-up design refers to the process of creating individual components and then bringing them together into an assembly, using constraints to define positional relationships.

This method is ideal when modeling parts that are unlikely to change as the design evolves, such as fasteners, motors, and other off-the-shelf components. Editing parts designed in this way requires manual changes to the part's sketches and features.

Top-Down Design

Top-down design refers to the process of creating parts directly in an assembly and using geometry already in the assembly as a reference.

This method is ideal when modeling components that have rules, but not necessarily exact dimensions for every characteristic. When you change the position or shape of referenced parts in the assembly, your top-down-designed component automatically updates its shape or position in real time.
A part being designed top-down by referencing the yellow cylinder locations and diameters. If the positions or diameters change, this part will update automatically.

Putting It Together With Constraints

Constraints are relationships between components and/or reference geometry that position or move components relative to each other. Two faces touch - a pin goes through a hole - 2 gears turn each other at certain rate - that kind of thing.

Constraints bring individual components together into an actual product. Standard constraints are focused on positioning and Mechanical constraints are focused on gears and pulleys.
A finished telescope positioning system brought together with constraints

Testing Mechanism Motion

After defining constraints, you can drag components of the model around and the motion will transfer accurately to other components.

Gears, pulleys, rack/pinions, and screws are special kinds of motion that have dedicated constraints, available in some versions.

Physical Properties

Instantly query important physical characteristics of a design. Some properties such as mass are aggregated from each component's material settings and rolled up. Other properties like Center of Mass also look at the position of components in an assembly.

Display data in standard or scientific notation.
Knowing physical properties like center of mass is critical to the design of this plane

Interference Detection

Ensuring overlapping parts are corrected before a design is finalized is an important pre-production step. Interference detection checks for overlaps globally or between specified components.
Various visualization tools make it easy to see where overlaps occur, and data relating to the amount of overlapping volume lets you decide if an overlap is significant.
Overlapping volumes between parts are highlighted.

3D Exploded Views

Manually or automatically explode models to reveal the way the components come together and to give a clear picture of assembly. Toggle part trails for your visualization preference.

Type a description for each step and publish to an interactive 3D PDF. Stakeholders can click each step to view animations.

Section Views

Section views are indispensable when analyzing a model to ensure proper fit, but are also helpful for visualization in general. Realtime section views let you drag up to 3 planes with instant view feedback.
Section views can also be used for modeling. Exposing a cross section with a precise section view and then projecting it into a sketch allows for rapid reverse engineering.
An example of 3 simultaneous real-time section views.

Global Parameters

Global Parameter files can drive multiple parts simultaneously. When designing each component, reference the same design variable file. Once in an assembly, you can edit the variable file and each component will update in real time.

Make extremely fast and predictable edits across multiple parts while eliminating human error.

Component Replacement

When changes to part requirements occur, you an easily swap one part or subassembly for another, with the ability to replace all instances or to select which to replace.
old connections
new connections
A before / after of a component replacement operation

Mirror And Other-Hand Components

Editable Mirror operations take advantage of symmetry in an assembly. In cases where a part is non symmetric, you can create other-handed parts automatically.
Mirrors cut out human error, increase efficiency, and automate the creation of other-handed components.
A collection of parts (yellow) used as the source for a mirror operation (white)

Circular And Linear Patterns

Associative, editable patterns delete tedious repetition from your workflow. Select individual components or entire subassemblies as the basis for a pattern.
Create linear patterns in one, two, or three individually controlled directions simultaneously.
A single subassembly (blue) patterned around the central axis (yellow).

Assembly Booleans

Assembly Booleans combine multiple bodies into one body and/or subtract a body from one or more other bodies. This tool is critical to processes such as injection molding where the molded component must be subtracted from one or more cores and cavities.
An injection mold designed by subtracting the desired part (blue) from the core and cavity (gray)

Assembly-Level Cuts & Holes

Create cuts and holes at the assembly level to capture manufacturing steps where multiple components are drilled or machined simultaneously. An assembly feature is the best way to convey this information.
Sketch in Assembly
Holes Through multiple parts
Before and after of creating a Hole feature through multiple parts in an assembly.

Illustration Mode

Enable the Illustration view type to turn the view into a style that looks like a 2D drawing. Use this style to rapidly reorient the model for screenshots.

You can also leverage the real time section views to have up to three active section planes.

These tools make creating instructions, manuals, and marketing materials easy and efficient.