This is an old revision of this page, as edited by 24.99.127.10 (talk) at 11:48, 21 February 2009 (→External links: clarifyed actionscript link). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
Revision as of 11:48, 21 February 2009 by 24.99.127.10 (talk) (→External links: clarifyed actionscript link)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff) | It has been suggested that Inverse kinematic animation and Talk:Inverse_kinematics#Merge Proposal be merged into this article. (Discuss) Proposed since October 2007. |
Inverse kinematics is the process of determining the parameters of a jointed flexible object (a kinematic chain) in order to achieve a desired pose. Inverse kinematics is a type of motion planning. Inverse kinematics are also relevant to game programming and 3D animation, where a common use is making sure game characters connect physically to the world, such as feet landing firmly on top of terrain.
An articulated figure consists of a set of rigid segments connected with joints. Varying angles of the joints yields an indefinite number of configurations. The solution to the forward kinematic animation problem, given these angles, is the pose of the figure. The solution to the more difficult inverse kinematics problem is to find the joint angles given the desired configuration of the figure (i.e., end effector). In the general case there is no analytic solution for the inverse kinematics problem. However, inverse kinematics may be solved via nonlinear programming techniques. Certain special kinematic chains—those with a spherical wrist—permit kinematic decoupling. This treats the end effector's orientation and position independently and permits an efficient closed-form solution.
Inverse kinematics is a tool utilized frequently by 3D artists. It is often easier for an artist to express the desired spatial appearance rather than manipulate joint angles directly. For example, inverse kinematics allows an artist to move the hand of a 3D human model to a desired position and orientation and have an algorithm select the proper angles of the wrist, elbow, and shoulder joints.
Other applications of inverse kinematic algorithms include interactive manipulation, animation control and collision avoidance.
See also
- Forward kinematic animation
- Forward kinematics
- Inverse kinematic animation
- Kinemation
- Jacobian
- Joint constraints
- Levenberg-Marquardt algorithm
- Physics engine
- Pseudoinverse
- Ragdoll physics
- Arm solution
External links
- Inverse Kinematics algorithms
- Robot Inverse Kinematics
- HowStuffWorks.com article How do the characters in video games move so fluidly? with an explanation of inverse kinematics
- 3D Theory Kinematics
- Protein Inverse Kinematics
- Simple Inverse Kinematics example with source code using Jacobian
- Detailed description of Jacobian and CCD solutions for inverse kinematics
- Basic Application of Inverse Kinematics using ActionScript