Inventor Presentation1 May, 2003 By: Jeff Wymer
There's more to designing and engineering than simply making 3D parts and 2D drawings. After putting in hours of hard work in designing and detailing, there is nothing more frustrating than to hear someone say, "There are difficulties with the final assembly." As designs become more sophisticated, the detailed prints are becoming increasingly complex. Fortunately, Autodesk Inventor offers a set of tools to convey assembly instructions to those on the shop floor. Inventor's presentation files allow you to create exploded assembly drawings and animations intended for assembly and maintenance of products. This month, we'll walk through the steps required to create them.
Let's start by defining some of the terms.
- An Exploded View is a view in which parts of an assembly are separated for unobstructed viewing.
- Tweaks refers to positioning adjustments made to assembly components in an exploded view. These adjustments allow you specify the distance and direction of movement to provide better visibility of the components and their relationships.
- Trails are lines in an exploded view that show the relationship of a component to the assembly. They indicate the direction and distance that a component was moved to create the view.
- A Sequence is a group of tweaks in the animation of an exploded assembly.
- A Task is a fitting or scattering operation in the animation of an assembly explosion. Each task in an animation consists of one or more sequences.
Creating Exploded Assembly Views
One of the many advantages of using a 3D design system is the ability to quickly and easily create 3D isometric views of models in drawings. Using presentation files--a special environment for creating exploded assembly views and animations--expands this functionality. Often, when documenting an assembly design, it is helpful to show the assembly in an exploded state, in order to document an unobstructed view of the components involved. Trail lines are often used in these views to show the relationship between these components in the assembly.
To create an exploded view, you first create a presentation file. After creating a presentation file, select the Create View command from the Presentation Panel. The resulting dialog presents you with a number of options. First, you must select the assembly file that you would like to base your exploded view on. Autodesk Inventor provides the capability to use a predefined design view, readily found within the assembly file, making it easier to apply a particular zoom setting, view angle, color, or style for the components involved. Next, you need to determine the preferred settings for the explode method. Essentially, you must decide if you would like to have Inventor automatically explode the assembly, based on assembly mate constraints, or if you would like to manually explode the assembly. The auto-explode feature applies the explosion factor that you specify to the mate constraints, which are then defined in the assembly. While the auto-explode method is quick, you will more than likely use the manual setting, because it provides more control over how the components are positioned in the exploded state. If you do have Inventor auto-explode the assembly, you must decide if you would like trails to be created to show vector of explosion.
Now that you've created an exploded view, it's time to put the finishing touches on the view. At this time you may choose to apply a few additional tweaks to some or all components (if manual explode was selected earlier). This is easily done by selecting the Tweak Components command, found on the Presentation Panel or accessed via a right-click in the graphics window. When starting this command, Inventor will present you with a dialog, as shown in Figure 1. The purpose of the dialog is to provide you explicit control of the location of your components. However, you may find that you will never use it because you can work dynamically in the graphics window. The first step in the tweak process is to select an edge or face to determine the direction of movement of your tweaked components. If you're only tweaking one part, I recommend selecting an edge or face on that specific component. Next, select the component(s) you want to manually move or rotate. After selecting these components, then you can select the axis of movement by selecting either the axis of the triad on the screen or the axis button in the Tweak Component dialog box. The x-axis will be pre-selected by default. You can dynamically drag to define the distance of the tweak; you can also input an exact distance in the dialog box. To apply the new tweaks and to add additional tweaks, simply select the clear button in the dialog box. You can add as many additional tweaks as necessary to convey your assembly design by repeating the above steps.
Creating Exploded Drawing Views
You can now convey this exploded assembly view to others by creating an exploded drawing view. When creating a base view, there's a Presentation pulldown box where you can select the explosion view from the presentation file. You can then select which view orientations you want to create, and annotate the drawing like any other assembly drawing file. If you make any changes to your presentation file, your drawings will update automatically, ensuring that they are always accurate.
Figure 1. Inventor's Tweak Component dialog box gives you full control over the parts when creating an assembly explosion.
Creating Assembly and Maintenance Animations
The tweaks you have created are organized in sequences, which grouped multiple tweaks into a single group that'll playback at the same time. For instance, a screw can translate and rotate at the same time by grouping the translation and rotation tweak into a single sequence. The best way to view the sequences is to change the browser view by choosing the browser filters icon and selecting Sequence View. You will notice that the view of the browser is now displaying the sequences as the parent objects.
From here you can move tweaks from sequence to sequence by simply dragging and dropping the tweaks between sequences in the browser. You may also create new sequences by selecting tweaks between different sequences and right-clicking and selecting the New Sequence option. Each sequence may have a different camera view applied to it, such as a specific view orientation. This allows you to focus in on the task at hand; for instance, if the step is to install the brake caliper in a car assembly, you can zoom in on the rotor and axle assembly to make sure the users focus is on this area. To set up different views, you can edit the sequence, change the view orientation, and choose the Set Camera option. You may also define the operation by inputting a description of the work being performed in the Description field of the sequence.
You may also have multiple instructions grouped into Tasks. For instance, you can have a task to define how to disassemble a brake caliper from the vehicle and another task to define how to assemble the caliper on the vehicle. This way, one presentation file can contain both maintenance instructions and assembly instructions.
There are a variety of ways to communicate these rich assembly animations. One is to create a standard AVI file. To do this, select the Animate icon from the tool palette or right-click and select Animate. From here you can simply animate your assembly by selecting play. You can also save the animation as an AVI file by selecting the Record (bulls-eye) icon. This allows you to select where to save the AVI file and name it. You will also be prompted to select the video codec you wish to use from those currently installed on your system. Once you've set these options, selecting play, will capture your presentation file as an AVI file.
Another way to show your presentations is by publishing them on Autodesk Streamline. The detailed information you filled in at the sequence and task level will be published and displayed during playback. The consumer will be able to perform interactive operations, such as adjusting the playback speed, modifying view orientations, selecting specific sequences to play, and pausing the assembly for interrogation. The consumer can also extract the property information attached to the assemblies and components (for instance, bill-of-material, part numbers, material, mass properties, and cost information). For further information on Autodesk Streamline, go to www.autodesk.com/streamline.
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