Muhammad Hamid ¹, Mohsin Jamil ¹, Syed Omer Gilani ¹, Shahid Ikramullah ¹, Muhammad Nasir Khan ¹, Mazhar Hussain Malik ¹, Ishtiaq Ahmad ¹

Affiliations
1 School of Mechanical and Manufacturing Engineering (SMME), National University of Sciences and Technology (NUST), H-12 Main Campus, Islamabad, PK

Abstract

Background/Objectives: Cranes are used to carry loads effectively. During movement, often undesired fluctuations of lifted payload occur, which needs to be controlled. Control is the basic requirement for desired operation of crane. Objective is to control the trolley position and swing angle of payload. Methods/Statistical Analysis: The continual flow requires an effective control methodology to achieve a high positioning control of the trolley carrying payload and suppression of swing angle of payload during operation. Optimal control techniques can be used to control these undesired vibrations. These techniques result in some undesired overshoot and undershoot causing the payload to swing prior to system getting stable. However if these techniques are combined with intelligent control techniques then a more stable system can be obtained. Findings: In this paper a hybrid controller called neuro-optimal controller has been used to control the swing angle of lifted payload by controlling the trolley position.The proposed technique of using a hybrid controller has stabilized the system by reducing the overshoot, undershoot and settling time. Application/Improvements: The proposed technique is very useful in many industrial applications. Experimental analysis can further provide the insight and limitations of the proposed techniques.

Keywords

Artificial Neural Network (ANN), Algebraic Riccati Equation (ARE), Back Propagation (BP), Linear Quadratic Regulator Controller (LQR), Neural Network Predictive Controller (NNPC), 3 Degree of Freedom (3DOF).

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Muhammad Sajjad Ahmad ¹, Mohsin Jamil ¹, Javid Iqbal ¹, Muhammad Nasir Khan ¹, Mazhar Hussain Malik ², Shahid Ikramullah Butt ¹

Affiliations
1 School of Mechanical and Manufacturing Engineering (SMME), National University of Sciences and Technology (NUST), H-12 Main Campus, Islamabad, PK
2 Department of Computer Science, Institute of Southern Punjab, Multan, PK

Abstract

Background/Objectives: Each structure tends to vibrate at particular frequencies, called resonant or natural frequencies. When a structure is excited by dynamic load with frequency coinciding one of its natural frequencies the structure experiences stresses and large displacements. In this paper effective mass participation factor criterion is used to solve the vibration problem in the ship mast. Methods/Statistical Analysis: The effective mass participation factor provides a measure of the energy contained within each resonant mode. Vibration problem originated when one of the antenna at top of mast was replaced by a new antenna with greater mass at same location. The overall mast structure started vibrating because of the resonance of natural frequencies of the mast structure with natural frequencies of rotary equipment. Findings: It caused interruption in sensitivity of equipment installed on the mast structure. Instead of fabricating the new mast structure, some alteration has been carried out on the basis of results obtained from modal analysis. Application/Improvements: The study is very effective to overcome the vibration problems in ship mast.

Keywords

Effective Mass Participation, Modal Analysis, Mode Shape, Ship Mast.

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