Complex Obstacle Drop


Upping the Ante


This exercise is designed to be an application of the information learned in Chapter 3 of the Animation Bootcamp course, especially the Obstacle Drop I and II lessons.

The assignment is essentially to animate a physics simulation. Using two or more different kinds of balls and an uneven ground, your challenge is to animate believable bounces and chain reactions that occur between your different balls. You can choose a simpler 2-ball interaction or more balls for a bigger challenge.

Simple obstacle drop

Complex obstacle drop


  1. Download the Complex Obstacle Drops: Source Files from the Downloads tab. Unzip and open one of the included .blend files with Blender. Also you’re welcome to create your own variation of balls and ground.
  2. Animate 2+ different types of balls dropping on an uneven ground and achieve believable chain-reaction-bouncing for each according to its type.
  3. Render your animation as an openGL viewport render.
  4. Upload your video to YouTube or Vimeo.
  5. Finally, submit your exercise by clicking the Submit Exercise button in the top-right corner of this page and pasting your video’s URL.

Exercise Questions and Answers

Ask a question and get an answer!

Submit your Question
  • Replies: 1

    When I try to insert a keyframe, it says “no suitable context info for active keying set”. All the previous exercises worked just fine.

    3 weeks ago

    • Replies: 0

      I found the answer: set the “Active Keying Set” to “Available” AFTER the setting the first frame. The file has it already set by default, so you must delete the Active keying set, create a keyframe with the bone, then clicking on “Available” once again

      3 weeks ago

  • Replies: 1

    This time I was getting along with the animation and suddenly the handles started to act differently. I was often toggling between free and vector, using the G key, but then that behavior changed such that the handles wouldn’t manipulate independently again. I was hobbling along using the S and R keys on the handles but it was acting oddly. The handles didn’t want to be independent or free. My question is; does this strike you as something I did to change this behavior, or maybe I’m dealing with a bug or something? Thank you for your time.

    7 months ago

    • Replies: 1

      It sounds like you may have accidentally changed the handles to aligned. But also make sure that you don’t have both handles selected or all 3 parts of the handle. That is the left side the middle vert and the right side.
      That’s probably all I can help you with at this stage I’m afraid.
      I hope you figure it out, it’s most likely something you pressed by accident. (don’t worry that happens all the time)

      7 months ago

      • Thank you. I was hoping it was something obvious. Lots of moving parts. Moving on!

        7 months ago