CPSC 526 Project

Purpose and Requirements

Possible Topics

• Your own project suggestion
  You can develop your own project suggestion. You may be able to suggest a project that directly connects with your interests, with a project in another course, or with your group presentation topic. I would be happy to discuss ideas with you.
• Dynamic simulation of walking using alternative physics engines
  We currently have example implementations of dynamic walking strategies such as SIMBICON using Open Dynamics Engine. It would be interesting to test these with other physics engines, such as Havok, PhysX, and Vortex, among others. The goal would be to see what the tradeoffs are in terms of numerical stability, simulation efficiency, types of contact models supported, etc.
• Animation of climbing motions
  Given a sequence of hand-and-foot holds on an extended vertical wall, plan and animate a motion of a human character using these holds in order to climb the wall. Either kinematic or dynamic animation is fine. You might look at the example motions in the game "Assassin's Creed" for some ideas. I suggest using a highly simplified human figure as a starting point.
• Dynamic walking with realistic tripping reflexes
  This project augments the existing 2D or 3D dynamic walking simulations with basic tripping reflexes. First, any reaction should occur with a delay, as opposed to current techniques which can respond instantaneously. Second, if an obstruction is detected early in a step, it should lead to the swing leg being lifted higher. If an obstruction is detected late in a step, the swing leg should be placed down sooner than normal.
• Optimization of walking motion for energy
  Optimize the control inputs of one of the existing walking simulations to achieve the most efficient walk possible, as measured in terms of energy per unit distance traveled.
• Statistical models of motion
  Experiment with one or more statistical models of motion. There is an entire spectrum of possibilities, ranging from simple to complex. Come talk to me for suggestions.
• Characters with personality
  Develop a simple kinematic character that exhibits significant personality, along the lines of Ken Perlin's work.
• Implementation of your own rigid body dynamics simulator
  Simulate particles, then rigid bodies, then articulated rigid bodies.
• Example-based inverse kinematics
  Split motion capture data into example data and test data. Implement an IK procedure that leverages the example data to solve for IK problems.
• Modeling the space of natural poses
  Using example pose data, develop a generative model based on Gaussian Mixture Models for natural human poses found in the CMU motion capture data set.
• Reinforcement learning
  Reinforcement learning is used in a variety of ways in state of the art animation research. Develop a demonstration of reinforcement learning. Developing a control policy for a simple dynamical system, e.g., pole-on-a-cart, is an excellent milestone.

Useful Resources

• 3D dynamics simulator: Open Dynamics Engine
  Open Dynamics Engine (ODE) (www.ode.org) is a useful starting point for projects involving 3D rigid body dynamics simulation. Various tutorials on using ODE on the internet. The SimpleControlFramework.zip framework provides a good starting point for working with ODE, as it provides OpenGL-based display as well as an XML file format for specifying the rigid bodies and their joints. It comes with an example that shows you how to specify and control a wriggling worm made from rigid body segments. If you run into issues, you can contact Stelian Coros (scoros@cs.ubc.ca), who developed the framework and the example, and he may be able to help you.
• 3D SIMBICON walking simulation
  The full source code for a 3D implementation of SIMBICON (see the ACM SIGGRAPH 2007 paper), built on top of Open Dynamics Engine, is available: http://www.cs.ubc.ca/~van/simbicon_cef/index.html. This will be useful for projects where you want to begin with a fully working dynamic simulation of walking, and then modify or extend it in various ways.
• 2D dynamics simulations
  Sometimes it is simpler to begin exploring control and simulation issues in 2D before moving to 3D. The excon framework ( http://www.cs.ubc.ca/~van/excon/index.html ) is a good starting point for such cases, and comes with basic simulation and control of a pendulum, two-link jumping acrobot, three-link luxo, a 2D Raibert hopper, a 5-link character controlled with SIMBICON, a seven-link biped, a cart-and-pole, and a simple model for steering trucks. As a related note, it is also possible to constrain the 3D dynamics simulator to do a 2D dynamics simulation. If you are interested in this, contact Michiel or Stelian.
• Motion-capture based animation
  The CMU motion capture database ( mocap.cs.cmu.edu ) is a great source for motion capture data. Basic software for reading and display can be found here: MocapPlayer-windows.zip and . The windows version compiles and runs fine for me, but I'm told that this is not always the case. If you find and fix this issue, I'm happy to give credit for this, as I haven't had time to look into the issue. Also come talk to me about the simple addition that is still needed to get motion blending working. Some basic instructions to get started on this code can be found in the following CPSC 426 assignment: a3.pdf.
• Matlab
  For some projects, Matlab may be a very useful toolkit. Explore the use of existing resources on the web for reading and displaying motion capture data in Matlab.