In this research, the positioning control of a water hydraulic servo cylinder system with the simple adaptive control （SAC） is discussed. Conventional model reference adaptive control （MRAC） also achieves good tracking performance for cylinder control, but the controller structure is much more complicated and has less robustness for disturbance in real application. Compared with MRAC, SAC has simpler and lower order structure, i.e. higher feasibility. However, no result has been reported on SAC application for water hydraulics. In this paper, we examined and evaluated the control performance of SAC on a water hydraulic servo cylinder system, and it was confirmed that SAC gives 1) better tracking performance compared with PI control, and 2) comparable control precision and higher robustness compared with MRAC.

抄録全体を表示

In recent years, Japanese society has been aging, engendering a labor shortage of young workers. Robots are therefore expected to be useful to perform tasks such as day-to-day work support for elderly people. Therefore, a tendon-driven balloon actuator has been developed for the robot hand in such environments. In this study, we have evaluated characteristics of force control of a balloon actuator using a predictive functional control (PFC) system. Predictive functional control is one of the models based on predictive control (MPC) schemes, which predict the future outputs of the actual plant over the prediction horizon and compute the control effort over the control horizon at every sampling instance. In this paper, PFC control performance of a 1-link finger using a pneumatic balloon actuator is reported.

抄録全体を表示

It is important to study a precise and practical way to predict temperature rise of oil hydraulic systems. It is interesting whether internal flow patterns have any effect on the temperature change in a cylinder. Nowadays, commercial CFD (Computational Fluid Dynamics) codes give accurate solutions of temperature as well as flow patterns. The authors have calculated the flow pattern in a cylinder using a reliable CFD code and have found that there is characteristic vortex flow with a strong three-dimensional effect on the flow pattern, and the internal flow patterns can be classified into two flow regions, a 3D vortex flow pattern and a 1D parallel flow pattern. So, it becomes possible to predict precisely and practically the temperature change in a cylinder by incorporating the difference of the internal flow patterns with a modeling method based on a lumped parameter system. A new method for prediction of temperature rise in a cylinder is proposed in this study.

抄録全体を表示