No abstract

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.

No abstract

No abstract

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.