This article develops the exact first-order endpoint Jacobian matrix f
or a general n-degrees of freedom tree-like robot with flexible links.
The Jacobian is developed in terms of the joint axes, the link deform
ations, and the relative position vectors using cross products. To hav
e the correct first-order endpoint Jacobian matrix, the second-order k
inematics is used to describe a flexible link. Using two local Jacobia
n matrices enables to write the endpoint Jacobian sub-matrix associate
d to a flexible link, which is similar to the column of the Jacobian a
ssociated to a joint. An example with a one-link flexible arm rotating
in a vertical plane illustrates the usefulness of the endpoint Jacobi
an in calculating the torque required to apply an endpoint force and t
he link deformation resulting from this force. An experimental verific
ation proves the validity of the developed Jacobian and suggests that
using only first-order kinematics results in serious errors in the pre
diction of the beam's curvatures and deformations. (C) 1995 John Wiley
& Sons, Inc.