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Animating with Inverse Kinematics in Adobe Animate

Adobe Animate: Bones Tool and 2D Puppet Armatures

Adobe Animate is a very good animation program.

It has many attractive and useful features, including layers and keyframes. With its built-in digital drawing and painting tools, the software works well for drawn animation, but it’s also ideal for cut-outs, largely because of the quick access to manipulation tools like free transform and its anchor point, grouping options, an onion skin, in addition to the straightforward editing of frames and keyframes.

On first glance, the program may only seem to generate flat-colour designs suitable for a cartoon look, but you can pursue visually complex projects, with both style and movement. For example, you could use Animate primarily for character animation and then export image sequences with transparencies to continue to work with additional layers in After Effects. The programs integrate nicely. Furthermore, to expand on a 2D cartoon feel, you should seek inspiration from other techniques and references, such as woodblock and lino-cut printing and illustration techniques.

With recent versions of Adobe Animate, it is now possible to link and parent objects/symbols using the Bone Tool. With this feature, you can hinge joints on a character, at the shoulders, elbows, hands, hips, knees, ankles, etc., to construct an armature that moves by parenting symbols and utilizing inverse kinematics. When you manipulate a character’s hand, the arm and shoulder will follow along.

The following descriptions cover the production steps, to get you started with building a rig and animating the puppet.

Setting Up a Puppet

You can create the puppet directly in Adobe Animate, or with Photoshop, artwork that has been scanned or captured, etc. But, use Photoshop to crop the pieces so they have minimal extra regions beyond the artwork. Otherwise, when it comes to animating the objects with Adobe Animate, you will have to manipulate symbols with large transparent regions, which will make their handling cumbersome.

For notes on how to use Photoshop to crop images, click > here.

From Adobe Animate, import the pieces to the Library (i.e., Main Menu > File > Import > Import to Library).

Important Adobe Animate Tools

Selection (V-key)

Transform (Q-key)

To scale and move the Anchor Point

Bone (M-key)

Sub-selection (A-key)


For information on Adobe Animate and Symbols, click > here.

In order to use the Bone Tool to link pieces and assemble the armature, you must turn the individual puppet pieces into Symbols:

  1. Go to the Library and drag a puppet piece to the Stage.
  2. From the Stage, click on the piece and then go to the Main Menu > Modify > Convert to Symbol (or, alternatively, press the F8 key, or context-click Convert to Symbol).
  3. From the Convert to Symbol Window, enter the following:
  4. Name: Give the object a short name
  5. Type: Choose “Graphic” (not “Movie” or “Button”)
  6. Registration: Click the square in the middle of the icon
  7. Press the OK Button

You should give the Symbols similar names as the original artwork. To organize the files in the Library, put the original pieces in a folder. To make a folder, click on the Folder Icon at the bottom edge of the Library, and name it Originals. Once you’ve converted objects, you can then make adjustments to the Symbols. They’re similar to Compositions in After Effects, in that, when you adjust a symbol, all instances of the Symbol in the Timeline will update and change.

  • For example, referring to the Properties Inspector, click on a Symbol and go to the Properties. Under Colour Effect, you can modify the Brightness, apply a Tint, use the Advanced (Alpha, Red, Green, and Blue), or adjust the Alpha (transparency).

To Prepare for Frame-By-Frame Cutout Animation

Turn off “snapping.” To do so, go to the Main Menu > View > Snapping and choose “Edit Snapping.” From the Edit Snapping Window, deselect the various options (i.e., Align, To Grid, To Guides, To Pixels, and To Objects). Doing so will make moving objects smoother because the objects won’t snap to screen pixels and guides.

Add the Graphic Clips to the Stage to begin to organize the rig. Use the Selection Tool to move the objects around.

Puppet Armature

When designing a puppet, you should use the pelvis or a core-symbol in the lower-torso region to help manipulate the puppet in broad strokes. Therefore, you should make a “core symbol,” which means making a simple object like an oval form and covert it to a symbol. You would then drag it to the stage and integrate it into the puppet design, to help pose, block in, and move the figure for key gestures, before you refine the animation with subtler character acting and follow-through motion. When using the symbol as a control, you may want to scale it up to make it quite large, so that you can easily grip on to move the figure around.

In the parent hierarchy, the top “parent” symbol should be the torso, which will be linked to the pelvis or core-symbol and then to the other puppet parts (see below).

To Hide Control Symbols Later On

Ultimately, to hide the core symbol later on, as a final step before rendering, so that it doesn’t export with the rest of the puppet and animation, go into the symbol itself, context-click on the layer and choose “Guide.” Doing so will turn the layer into a Guide Layer, where objects and images do not show when sequences are rendered as QuickTime moves or image sequences.

A Scheme for the Puppet Construction

To construct an armature/rig, use the Bone Tool (M).

  1. Begin the armature chain by establishing the torso as the parent, anchoring up around where the shoulders will be, in the middle of the chest and upper-torso region. Starting  from there, make a connection to the core control or pelvis. All other objects/symbols will be “children” of the “torso parent.”
  2. Start again with the Bone Tool at the control/pelvis and connect to the far hip (top of the far upper-leg), to the knee (top of the far lower-leg) and then the the far ankle/foot.
  3. Go back again with the Bone Tool at the control/pelvis and connect to the near hip (top of the near upper-leg), to the knee (top of the near lower-leg) and then to the near ankle/foot.
  4. Back at the torso, proceed with the shoulders. From the original torso location, use the Bone Tool to link to the top of the far arm (at top of the far upper-arm), to the elbow (top of the far lower-arm) and then to the near hand.
  5. Once more, go back to the original torso location and use the Bone Tool to link to the top of the near arm (at top of the near upper-arm), to the elbow (top of the near lower-arm), and then to the near hand.
  6. Finally, go back to the torso again and link to the head, and so on.
  7. If you would like to add over clothing of some kind (e.g., a coat, skirt, etc.) to the core-symbol, you can use the Bone Tool to link from the pelvis/core-control to that particular symbol.

Those steps should make a working armature. To edit the limbs, use the Transform Tool (shortcut with the Q-key) to move the objects/symbols in place, and to adjust the anchor points.

To change the length of the bones, use the Sub-selection Tool (A) + Command

To move the pivot points around, use the Transform Tool (Q)

You can adjust the length of the bones, position of the pivot points and the like as much as necessary along the way. In fact, you should spend time playing with the rig, moving the joints around (utilizing the V-key), etc., until everything seems to move correctly.

Furthermore, as you will set poses/keys along the Armature Layer in the Timeline (i.e., context-click on a frame and choose Insert Pose), you can, and may want to, change the position of particular symbols/pieces as well as their anchor points. Know, however, that Adobe Animate will in-between the changes if there are frames between the poses or key frames.

Enabling & Constraining Joints

When you move the puppet, it might seem unwieldy at times.  To calm down that movement, you should use the Selection Tool (V-key) to click on a bone and then go into the Properties Inspector to disable the rotation (or horizontal and vertical movement) of a particular pivot point, and then enable it again later.

Joint: Rotation:
Check and un-check the Enable and Constrain Buttons when necessary (e.g. to limit the degrees of rotation)

Joint: X Translation:
Check and un-check the Enable Button when necessary — to move the object/symbol horizontally

Joint: Y Translation:
Check and un-check the Enable Button when necessary — to move the object/symbol vertically

You can also set the tension on the bones, so they don’t twirl and swing quickly and uncontrollably. Click on a particular bone with the V-key, go to  the Properties Inspector, find Location (near the top of the Inspector) and, under Speed, crank down the amount, to less than 100%, depending on the amount of tension you prefer. You can also adapt the amount along the way as you forge ahead with the animation.

Walking Motion – Enable/Disable & Pin Joints

When it comes to animating your character, before moving the figure (i.e., before you move the torso and core symbol horizontally), you should:

  • “Pin” the the two feet
  • Then, move the torso/parent horizontally or vertically, to pose most of the puppet
  • Then, move the feet

To pin the feet, click on each of the ankle/foot bones and, going to Location section in the top-region of the Properties Inspector, enable the “Pin” button for each foot.  Pinning the feet will be analogous to adding a bit of masking tape or blue-tack under the foot of an actual puppet to stop the foot/leg from shifting or bumping as you manipulate the objects. Disabling the Rotation of the weigh-bearing foot will really tack down the part, so the feet don’t slip.

For the weight-bearing foot (i.e., the one that carries the character’s weight when she/he walks), you should temporarily “disable’ the Joint Rotation (but you would enable it again in a couple of steps hence).

To move the character (i.e, his parent torso), use a combination of the torso and the pelvis/core symbol to shift the character forward. But, in doing so, temporarily turn off the Rotation and keep to the X-Translation for the moment.  You would make the change in the Properties Inspector. After that, you might want to then turn off the X-Translation and then shift the Y-Translation, to add a bit of up-and-down motion (e.g., for squash and stretch). This way, you can move that torso forward without twisting the object on its axis.

Onion Skin

As you animate, you should turn on the Onion Skin, to refer to the progressive phases of the movement.  The button to activate the Onion Skin is on the lower-ribbon of the Timeline, immediately to the right of the Play & Rewind Buttons.

Properties Inspector > Looping

Important! If you plan to use Graphic Clips with more than a single phase (e.g., for position rotations), you must turn the looping off, otherwise your puppet will do a strange dance performance kind of thing. To turn the looping off, click on a particular Graphic Clip on the Stage and then, referring to the Properties Inspector go to Looping.  From the pull-down menu, select Single Frame. To access specific phases or key-positions in the particular symbol, enter the frame number and press the Enter Key.

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