Mechanical Engineering / Makina Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/4129
Browse
5 results
Search Results
Conference Object Citation - Scopus: 3Four-bar function generation using excel solver(Springer, 2023) Söylemez, Eres; Kiper, GökhanThe Chapter presents a simple and efficient way of approximating a function with a four-bar mechanism using four or five design parameters including one or both of the initial crank angles. The method only involves solution of linear set of equations and evaluating determinants, whereas nonlinear equations are numerically solved using a simple program such as Excel. So, the method is easy to explain and can be taught in an undergraduate course along with the wellknown linear three precision point synthesis problem. Precision point synthesis, order synthesis, mixed order synthesis, least squares approximation and extreme point synthesis can all be treated using the same method. The proposed method is illustrated with numerical examples for all mentioned synthesis problems and shown to be quite efficient with very low amount of structural error values.Conference Object Function Generation of a Watt Ii Type Planar Mechanism With Prismatic Output Using Decomposition and Correction Method(Azerbaijan Technical University, 2017) Kiper, GökhanThe method of decomposition is a useful method for function generation with multi-loop mechanisms. Recently introduced correction methods applied together with the method of decomposition allows the designer to cancel out the errors in the first loop of a two-loop mechanism with the errors in the second loop. In this study, the decomposition and correction method is applied for a Watt II type planar six-link mechanism with prismatic output. Five design parameters are defined for each loop resulting in ten design parameters in total. The design parameters are determined analytically. The generation error is decreased by adjusting free parameters such as limits of some joint angles and parameters due to the decomposition of the function to be generated, while considering several constraints such as link lengths ratios and ranges of the joint variables. The success of the method is illustrated with a numerical example.Article Citation - WoS: 3Citation - Scopus: 4Function Generation With Two Loop Mechanisms Using Decomposition and Correction Method(Elsevier, 2017) Kiper, Gökhan; Dede, Mehmet İsmet Can; Maaroof, Omar W.; Özkahya, MerveMethod of decomposition has been successfully applied to function generation with multi-loop mechanisms. For a two-loop mechanism, a function y = f(x) can be decomposed into two as w = g(x) and y = h(w) = h(g(x)) = f(x). This study makes use of the method of decomposition for two-loop mechanisms, where the errors from each loop are forced to match each other. In the first loop, which includes the input of the mechanism, the decomposed function (g) is generated and the resulting structural error is determined. Then, for the second loop, the desired output of the function (f) is considered as an input and the structural error of the decomposed function (g) is determined. By matching the obtained structural errors, the final error in the output of the mechanism is reduced. Three different correction methods are proposed. The first method has three precision points per loop, while the second method has four. In the third method, the extrema of the errors from both loops are matched. The methods are applied to a Watt II type planar six-bar linkage for demonstration. Several numerical examples are worked out and the results are compared with the results in the literature.Article Function Generation Synthesis of Planar 5r Mechanism(IFToMM, 2013) Kiper, Gökhan; Bilgincan, Tunç; Dede, Mehmet İsmet CanThis paper deals with the function generation problem for a planar five-bar mechanism. The inputs to the mechanism are selected as one of the fixed joints and the mid-joint, whereas the remaining fixed joint represents the output. Synthesis problem of the five-bar mechanism is analytically formulated and an objective function is expressed in polynomial form. Function generation synthesis is performed with equal spacing and Chebyshev approximation method. The four unknown construction parameters and the error are evaluated by means of five design points and the coefficients of the objective function are determined by numerical iteration using four stationary and one moving design point. Stationary points are placed at the boundaries of the motion and the moving point is re-selected at each iteration as the point corresponding to the extremum error. Iterations are repeated until the values are stabilized. The stabilization usually occurs at the third iteration. By this method, the maximum error values are approximately equated, hence the total error is bounded at certain limits. Finally the construction parameters of the mechanism are determined.Book Part Citation - WoS: 3Function Synthesis of the Planar 5r Mechanism Using Least Squares Approximation(Springer, 2014) Kiper, Gökhan; Bağdadioğlu, Barış; Bilgincan, TunçIn this paper, the problem of function generation synthesis of planar 5R mechanism is studied using the least squares approximation method with equal spacing of the design points. The study represents a case study for analytical function generation of multi-degrees-of-freedom systems. The planar 5R mechanism is designed with a fixed input joint and a moving input joint adjacent to the first input, whereas the remaining fixed joint is the output joint. The input/output relationship of the mechanism is expreseed as an objective function in polynomial form with four unknown construction parameters. The objective function involves nonlinearities, however the problem is linearized using Lagrange variables. The linear system is solved and finally the construction parameters of the mechanism are determined. A numerical example is presented as a case study.