Evaluation of a possibility of estimation of reaction force of simple hydraulic system using sliding perturbation observer

In radiation contaminated area sensors have high risk of malfunction, and human cannot work in this area. Therefore, master and slave system without sensors is needed. In this paper, the reaction force estimation for hydraulic system is evaluated. Previously, estimation of reaction force using sliding perturbation observer has been applied to electric motor system. However, hydraulic system has different elements which are uncertain parameters such as compressibility and viscous friction from electric system. For this estimation, hydraulic system is modelled by using signal compression method to simplify the system. Position control is used in experiment. The estimated reaction force is compared between calculated force which calculated with elastic modulus of spring and depth. The estimated force has error with calculated force because the calculated force is not concern about hydraulic system's internal error. However, the force have tendency of following calculated force.