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APPENDIXA-TERMS AND DEFINITIONS

Robotics and Systems Control

position and orientation in free space.

A single rigid body in free space has six

Kinematics- Computation of the absolute position of all parts of a creature, given the

relative joint angles. In animation, kinematics typically refers to the specification or manipulation of the joint angles and velocities without regard to physics.

Inverse

Kinematics

-

Computation

of

the

intermediate

joint

angles

from

absolute

Dynamics- Computation of the accelerations of the links of an articulated figure using the

laws of physics.

Inverse Dynamics- Computation of the torques and forces required to be applied to a body

to achieve desired accelerations.

Centre of mass (COM)- The single point on a body through which a linear force can be

considered to act, defined as:

M

where M is the total mass.

System state- The set of variables required to fully specify the position and velocity of

every point on an object.

The system state of an object consists of its degrees of

freedom and their derivatives. Figure A-1 shows the two components of the state for