ABSTRACT: Control algorithms developed originally for force controlled normal mode testing on large aircraft
structures, then for six degrees of freedom earthquake simulators, are appropriate to the challenging application
of centrifuge earthquake simulator control. Twenty years of experience with multi-actuator multidegree
of freedom control are applied to the broadband real-time control of earthquake simulation. Earthquake
simulation control on the centrifuge has often previously been performed assuming a single degree of
freedom, even if these simulators used multiple actuators connected in parallel. A vibration controller designed
for both general-purpose single and multi actuator-testing fits perfectly this application. It generates
and sends all types of signals (random, sine, shocks, transients, time domain replication) to several actuators
set in a single or multiple axes configuration connected to a shake-table or directly to a structure. Closed loop
control is performed in any of these situations. This paper presents the theoretical aspects of MDOF (Multi
Degree of Freedom) control and the different features of the vibration controller including aspects of the
closed loop (such as correction and accuracy) within defined safety limits, measurement channels and the security
management of the tests.