4/1/2014

NX CAD In-Depth Tips: How to Create Simple Assembly Animations

One of the requests we received from our recent “What’s New in NX9″ seminars was how to do simple assembly animations.

So, here’s what you do!

PLAN THE ANIMATION

Number of Frames: There is a trade-off between the number of frames, movie size, and overall impact of the information created.  For reference, the average cartoon is 6-12 frames/second.  A movie is 24, and many broadcasts are 30.  NX has a simple playback speed adjustment you can use throughout this range.  In general, too few frames will result in a hard-to-understand, jerky slide show effect.  Too many frames and the movie create process (and resulting file) may be large, and may not play back well on some devices, such as mobile.

Assembly sequence:  Another element of animation planning is to determine whether or not multiple movies can be derived from the same assembly sequence.  Often, sequencing a movie by disassembling an assembly yields both:

  1. An assembly movie (by outputting it backwards)
  2. The forward-moving disassembly movie

You may want to move the camera around to various vantage points to communicate the process better.

Display size:  Size the NX window to control the overall movie output size and screen area.  Consider hiding datums and turning off the WCS display.

Colors and attributes:  We recommend a solid white or black background to make best use of the encoder built into NX.  Use clear, strong colors where possible and limit the use of transparency and other effects.

SAVE OFF A WORKING COPY OF THE ASSEMBLY

We recommend doing this at least the first couple of times.  In practice, having sequences in a production assembly won’t be an issue; this is less about data loss, and more about having the freedom to quickly generate the movie, change colors, and to hide/show components as needed.

UNDERSTAND THE PROCESS

  1. Prep the data to be made into a movie (colors, background, components, etc)
  2. Generate one or more assembly sequences
  3. Output movie files
  4. Play movies back to verify intent is communicated
  5. Optionally, post-produce files to add voice-over, titles and other transitions and effects
  6. Repeat as necessary

Now, let’s get started!


STEP 1: PREP THE DATA
If you’d like to follow along, you can find the sample assembly here.

Here, you can see that the NX window is sized with a longer aspect ratio to allow for landscape movies.  Adjust the window to suit your desired output.  Note the gradient background, lack of part colors and the visible WCS and assembly coordinate systems.

5612222.png#asset:571

Here is the sample with a solid background, all irrelevant things hidden, and easily distinguished part colors.

5871666_orig.png#asset:572

STEP 2:  GENERATE ONE OR MORE ASSEMBLY SEQUENCES

Now it’s time to make a sequence:

5007194.png#asset:573

Once inside the sequencing task, select “new” as shown:

652289_orig.png#asset:574

Let’s get familiar with the basic sequence tools outlined in green:

8282069.png#asset:575


9857227_orig.png#asset:576 Puts current view into the sequence.  Move, pan, rotate the part until you think the view makes sense, then use the command to add the camera to the sequence.


5664018_orig.png#asset:577 When you use this command, you select components that will be removed from the movie.  Typically, you move something away from its assembled position, then apply disassemble to make it disappear.


2820331_orig.png#asset:578 This command works opposite of the disassemble command.  You use it to have something pop out onto the screen, then move it into the assembled position, optionally moving the camera as needed.


485923_orig.png#asset:579 The workhorse of sequences.  When you insert a motion, you get to select components to move, then use the dynamic coordinate system to move them in the 3D space.  Each movement you do adds to the sequence.  Rather than combine many short moves in one operation, consider using this command a few times in a row.  Move, rotate it, move it again, disassemble it, etc. 

When you use insert motion, you get the motion tool bar:

2550935_orig.png#asset:580

Selected components look like this. Notice how the next two icons light up?  Those are the ones you need to position the component away from its assembled position, or assemble it.

8046597.png#asset:581
5050179_orig.png#asset:582 “Move component” moves the component according to how you manipulate the coordinate system shown here: 

3334941_orig.png#asset:583


3572536_orig.png#asset:584 You can also use this icon to move the coordinate system without moving the component (say, to realize a rotation axis off the component).


Move the object to its intended position, and use the green check mark  to insert that move into the sequence.

Continue with moves, camera captures, disassemblies and/or assemblies , until the sequence is complete.

CHECK YOUR PROGRESS WITH THE ASSEMBLY SEQUENCE NAVIGATOR

You can delete steps, go to them, cut, copy, etc. from the navigator.

6457307_orig.png#asset:585

Use the playback panel to review your movie before it’s output.  Select a playback speed, forward, begin, end buttons to view the sequence.  If it looks good, you can go to output the movie!  Otherwise, edit your sequence until you are satisfied.

5394716_orig.png#asset:586

This is the movie output command.  You will be asked for a movie output name, simply provide one.

4379118_orig.png#asset:587

NX will run the sequence, and will output the graphics window as you have sized it.

2331484_orig.png#asset:588

And that’s it!  Making a sequence doesn’t take long at all, and the movie file outputs are useful in a lot of contexts and a lot of devices.

Do you have any tips to share, or any post-production, third party programs you have used to improve your movies?  Let us know!

NX CAD
Article