Enhancing control robustness of a 6 DOF parallel testing machine

For the first time, a Nooru-Mohammed test was realized using a new kind of loading machine based on gough platform. However, it has been shown that boundary conditions on the concrete specimen are not respected. As a consequence, a new control strategy needs to be developed. This paper aims at applying a well-known control loop based on hybrid force/position law to a loading application. This new control algorithm has been developed according to the task and the structure specificities. Indeed, it permits to realize multi-axial test where the boundary conditions are controlled and respected by using the extra degrees of freedom.