The dynamic formulations of manipulators lead to a set of highly nonlinear and
strongly coupled differential equations which represents the dynamic model of a
manipulator. Beside many other forces, this model describes the actuator forces
(or torques) which cause the manipulator joints to move. In this paper, manipu‌lator joints are modeled as elastic springs with joint stiffness in order to impose
elastic forces to the dynamic system model and to monitor their influences
when speeding up the manipulator end-effector. The kinematic relationships are
described by using the zero-reference-position method. Both the inverse and
direct dynamics problems are developed by appl~ng Kane's dynamical equations
as an analytical tool. A Stanford-type manipulator is considered as a numerical
example. The implications of the results are monitored, compared and justified.