Improved Fuzzy Sliding Mode Theory And Its Applied Research In The Welding Process

Intelligent welding technique is a very promising approach for industrial welding technology, which plays an important role in modern technology for manufacturing industries. At present, although researches on welding techniques mainly center on the intelligence and new materials for controlling methods, the problems of splashing and material molding are still the focus and nodus of researches. Drawing on and learning from achievements by predecessors, this paper tries to solve these two problems to the best of my ability. Generally speaking, the stability of welding process requires the stability of welding quality under the circumstances of parameter disturbance by welding equipments. When fluctuation in input voltages or inconformity of welding materials occurs, the effect of welding is basically impregnable within an appropriate range. For the purpose of the good quality of welding and welding molding, the lengths of electric arcs and the stability of welding process must be guaranteed.Through analysis of the characteristics of CO₂ welding, this magisterial thesis is trying to work out the possible solutions to these two problems of splashing and welding molding by applying the approach of intelligent controlling and its stress is on the effect of welding and intelligentized welding. Fuzzy Theory and Slide Mode Theory is two methods of great importance in modern controlling theories. Fuzzy Controlling Theory is a computer control theory based on fuzzy convergence theory, fuzzy linguistic variables and fuzzy logical ratiocination. It is a non-linear and intelligentized control, which has been an important and effective way for intelligent controls. Professor L. A. Zadeh from California University put forward this theory in 1965 and since then extraordinary progress has been made in its theory and practice, which demonstrates its mighty application values.The advantages of Slide Mode Control are displayed during the controlling process when several adjusters are switched in order to make every single structure maintain good capability so that the system will gain stable performance. What's more, it also has the advantages of invariability, speedy switching and simple...