How To: Create a Motion Trail in Maya 2011

Motion trails in Autodesk Maya can be very handy at times when animating your scene. Keying a bone/joint or other object every so many frames can take up quite a bit of time and can sometimes be a big hassle, too. I have found many times when I could have really used one. I also don't like to search the Internet with a question and not find an answer (at least, without paying for it). So in this how-to article, I will demonstrate going about creating a simple (or complex) motion trail to make animating your scene a little easier and time saving.

Step 1 Creating Your Scene

In order to animate anything in Maya, you must first have something to animate. We will create a simple scene where we have a basic object, such as an aircraft, and maybe a sky with some birds.

If you have all ready created a scene with an object to move and a prop, you can continue to Step 2.

Tips

• It is always better to start simple in a new scene when learning the basics and functions of Maya. That way you can set the scene up clean-like in the project you want to implement these techniques into. It can also prevent unwanted effects that may screw up your scene.

If you don't want to spend the time modeling an airplane, or if you feel your self confidence may not be desirably high when comparing your model with the example(s), you can download an aircraft from TurboSquid for free (copyrights apply). Here is the model used in this how-to example.

Step 2 Creating Your Motion Path

Now that our scene is set up with an object (aircraft), we want to follow a given path and a prop (building or bridge) to show the path is working for that object (object is moving during play). We can now create a path for which to follow.

To do this, choose Create -> CV Curve Tool -> ? (Options). 

In the Option window that pops up, make sure that '3 Cubic' is selected. We'll now start drawing and shaping the trail. If you don't know already, to shape an already created curve, just right-click on the curve and choose Control Vertex. This will display the vertices that can now be altered. Be sure you have at least 4 points created or this will not work!

For this example though, I am just going to create a strait line and maybe an angle/minor rotation... after all, flying aircrafts do not go all over the place (unless they are crashing).

Step 3 Attaching Your Object to the Motion Trail

It is time to attach our aircraft to the motion trail.

First, we need to open the Outliner window: we can do this by choosing Window -> Outliner. In the Outliner, we need to select our aircraft group. Ctrl + Click the curve we created.

Tips

• If your model is not in a group or your model has multiple separate associated parts to it, you can make a new one from the object/collection by selecting the model and all it's parts by pressing Ctrl + G or by choosing Edit -> Group in the menu.

The menu bar now needs to be set to Animation for the next part. To do this, select Animation in the upper left-hand corner or press the hot-key 'F2'.

Now choose Animation -> Motion Paths -> Attach To Motion Path -> ? (Options). Reset all the options (Edit -> Reset) to start with fresh settings to alter. Change the following settings:

-> Front Axis: Z  -> Follow: true  -> Bank: true  -> Bank Limit: 30

You can alter these setting to experiment with their functions, but for now, I will use these settings to work with. Click Attach to attach our aircraft to the curve (motion trail).

Step 4 Play & Test Run

The final thing you would need to do is play the animation. If you did it right, the object should follow your path. You may need to alter some of the motion path's settings because in some cases, the air plane could be flying backwards or in the wrong direction. You can select the curve and in the Channel Box under OUTPUTS, select Motion Trail 1 to alter the path settings.