  This work presents the estimation of the parameters of an experimental setup,
which is modeled as a system with three degrees of freedom, composed by a
shaft, two rotors, and a DC motor, that emulates a drilling process. A Bayesian
technique is used in the estimation process, to take into account the
uncertainties and variabilities intrinsic to the measurement taken, which are
modeled as a noise of Gaussian nature. With this procedure it is expected to
check the reliability of the nominal values of the physical parameters of the
test rig. An estimation process assuming that nine parameters of the
experimental apparatus are unknown is conducted, and the results show that for
some quantities the relative deviation with respect to the nominal values is
very high. This deviation evidentiates a strong deficiency in the mathematical
model used to describe the dynamic behavior of the experimental apparatus.
