Abstract: In this paper, controlling a rigid robot manipulator driven by hydraulic system is considered. Due to changing of inertia moment of the manipulator as well as the effect of fiction of hydraulic system, the dynamics of the robot arm is highly nonlinear. Therefore sliding mode control method is applied. Sliding mode control is a robust control method. It provides a symmetric approach to the problem of maintaining stability and consistent performance in the face of modeling imprecision. Numerical simulations and experiment results of the control system are presented. The results show the extremely good robustness of the proposed method.

Abstract: This paper presents the implementation of the combination of time-series modeling and nearest neighbor classification method in detecting common faults in rotating machineries. In this paper we propose the utilization of parametric distance as an instrument to diagnose faults. The parametric distance is defined as the Euclidean distance between the vector of parameters of an unknown fault and the vector of parameters of known faults obtained from the learning stage. Since the vectors are defined in a hyperspace spanned by the parameters of the identified time-series model, the parametric distance is definitely metric. The method has been successfully implemented in the laboratory using a simple vibration test rig.

Abstract: Development of environmental friendly hydraulic fluid has a major influence in ecologically benign environment. This future type of oil should be non-toxic, biodegradable and ecological benign. Subsequently, it becomes crucial to recognize the sustainability of such oil in maintaining a high system performance which resulting in tremendous contribution towards machinery technology. Furthermore, the development of methods to evaluate the actual performance of hydraulic fluid has been of great interest. In this project a hydraulic test rig which incorporates LabView data acquisition system (DAQ) was built to conduct endurance test where it can be operated for up to 280 bar, running continuously with several safety features. The rig was used to test the oil and other stringent parameters, running for nearly 10000 hours at the temperature of 70 ºC under constant pressure of 70 bar and pump speed of 40 Hz. Major factors in the decrease of mechanical efficiency are thermal heat, friction, aging behaviour and contamination of the plant oil. Explained in this paper are the features of the hydraulic system built to evaluate the performance of plant oils, accompanied by some results for evaluating the suitability of the usage of plant oil as hydraulic fluid.