Editing Robot kinematics (section)

===Static force analysis===

The principle of [[virtual work]] yields a set of linear equations that relate the resultant force-torque six vector, called a [[screw theory|wrench]], that acts on the end-effector to the joint torques of the robot.  If the end-effector [[Wrench (screw theory)|wrench]] is known, then a direct calculation yields the joint torques.

The '''inverse statics''' problem seeks the end-effector wrench associated with a given set of joint torques, and requires the inverse of the Jacobian matrix.  As in the case of inverse velocity analysis, at singular configurations this problem cannot be solved. However, near singularities small actuator torques result in a large end-effector wrench. Thus near singularity configurations robots have large [[mechanical advantage]].