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Magnetic levitation is significant in almost all arenas of engineering. This principle is used to levitate objects such as a bullet train, flywheel, etc. This paper presents an experimental setup of Magnetic Levitation System (MLS) in which a ball is levitated to a desired position and is sustained at a desired level for a stipulated time. The ball position is measured using an optoelectronic sensor and a controller is used to determine the time span of the ball at desired heights. To achieve this, a Sliding Mode Controller (SMC) is designed in such a way so as to regulate the current, which in turn controls the position through an electromagnet. Real-time observations of such ball positions have been recorded and compared to those of conventional PID (Proportional Integral Derivative) and robust SMC. Disturbance rejection, servo operation and set point tracking have also been tested and verified for the same. The outcome of such results processed through MATLAB proves that SMC's performance is predominant over other controllers.

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Electro Hydraulic Servo Systems (EHSS) offer fast response in different industrial aspects such as heavy machines, cranes and robots. To obtain a precise piston profile and to achieve the designed speed, a Sliding Mode Controller (SMC) for the duration of piston extension and retraction is presented in this paper. The novelty lies in the development of a practical profile connecting the system supply pressure dynamics to the duration of piston extension and retraction. Based on the curve fitting technique, a quadratic profile is designed for a practical hydraulic press. The Sliding Mode Controller is employed to achieve repeatable tracking of the profile generated with guaranteed soft seating velocity, thereby increasing the lifetime of the hydraulic press. The performance of the proposed controller is compared with the baseline Proportional Integral Derivative (PID) controller with square wave as well as exponential wave tracking tests in simulation and experimentation which confirm the effectiveness of the proposed control scheme.

This investigation considers the study of pH system in Common effluent treatment plant (CETP). For this purpose, Perundurai Common Effluent Treatment (PCETP) is taken for study. Waste from textile industries is rarely neutral. Certain processes such as reactive dyeing require large quantities of alkali but pre-treatments and some washes can be acidic. It is therefore necessary to adjust the pH in the treatment process to make the wastewater neutral. This is particularly important if biological treatment is being used, as the microbes used in biological treatment require a pH in the range of 6-8 and will be killed by highly acidic or alkali wastewater. In PCETP, the wastewater is mostly alkali wastes (high pH). For this purpose, hydrochloric acid (HCl) is added to maintain the pH value from 7.5 to 7.8 to save the microbes used in biological treatment as well as to reduce the wastage of chemicals.