الفهرس 
CHAPTER 1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Mechanism’s optimal synthesis is an essential issue for mechanism design of the practical engineering applications in order to accomplish the designer requirements. The crank rocker of four bar planar mechanism is mostly applied in mechanical systems. Moreover, this mechanism’s synthesis procedures can be extended to apply for other planar mechanisms.
Many researches have been devoted to optimal synthesis of crank rocker mechanism using the suitable design optimization techniques. Some of these techniques are dealing with a specified path generation considering the transmission angle as design constraint. As well as, many of specified design values were considered as rocker stroke, time ratio, minimum transmission angle and equal deviations of transmission angles. Maximization of transmission performance from input to output link, bearing’s shaking force reduction in addition avoiding jamming and locking are playing an important role during the mechanism design. Transmission angle deviation can be adopted as desired task of effective design tool. Kinematic synthesis is the first design stage that identifies mechanism arrangements and length of links for satisfying the desired function.
This research presents a detailed analysis methodology for optimal synthesizing lengths of planar crank-rocker mechanism with desired tasks for satisfying a certain transmission angles deviations. The deviations are considered as the absolute values between optimum transmission angle (90◦) and their extreme values. The definite task is one of three alternatives case studies. The analytical methodology includes deducing six design equations of equal constraints, which represent relations between the desired task and mechanism lengths and characteristics or performance requirements.
Results are located within a feasible design domain, which facilitate selecting the preferable optimal mechanism to accommodate its application requirements and know the limits of time ratios, transmission angles or output strokes. Also, optimal synthesizing results of crank-rocker mechanism’s lengths are verifying any desired task which coincide with cases have the corresponding six deduced design equations and concurring with the results of different approaches in some earlier literatures. Optimal synthesized of centric or inline crank-rocker mechanism lengths presented as a new graphical methodology using only the desired task and one deduced equation. Several examples are presented to illustrate the versatility of this methodology. Also, novel theorems are clarified to be good helpful and useful tool for such mechanism’s designer and application requirements which describing the relations between the desired synthesis task and the class of crank-rocker four bar mechanism or the six design constraint equations.
Furthermore, this research deals with an integrated design strategy for evaluating the mechanism’s performance through two stages. These stages are dealing with kinematic and dynamic evaluations. The performance requirements depend on fulfillment kinematic, dynamic requirements and expecting output motion characteristics. The influence of transmissions angles deviations and the corresponding optimal mechanism lengths on the performance specifications is evaluated. The inertia effects are taken in account at the dynamic evaluation stage. Numerical examples and appropriate diagrams are illustrated of the desired three synthesis tasks for satisfying the definite transmission angles deviations.