Theoretical and experimental dynamic performance optimization of planar mechanisms using adjustment systems and mechanical generators


Thesis Type: Doctorate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Mechanical Engineering, Turkey

Approval Date: 2015

Student: HAKAN MENCEK

Supervisor: REŞİT SOYLU

Abstract:

Main focus of this study is to optimize the dynamic characteristics of planar mechanisms by utilizing two novel systems: adjustment systems and mechanical force/torque generators. Both theoretical and practical aspects of the problem are considered. The adjustment systems are special auxiliary systems that are designed for changing the inertial parameters of the mechanisms during the operation, whereas mechanical force/torque generators are over-constrained, energy efficient planar mechanisms which are able to generate any desired force and torque variations while obeying physical limitations. In the theoretical part of the study, firstly, general analysis and design methodologies for the adjustment systems and the mechanical force/torque generators have been developed. Then, usage of these novel systems for dynamic performance optimization of the planar mechanisms have been considered. It has been shown that the adjustment systems are better in minimizing shaking force, shaking moment and actuator force/torque fluctuations. On the other hand, it is observed that the mechanical force/torque generators perform especially well for minimizing the total energy consumption of the mechanisms, since they are energy efficient systems. In order to test the validity of the theoretical results, test set-ups involving planar mechanisms, a data acquisition system and prototypes of both the adjustment systems and mechanical force/torque generators have been designed and constructed. At this stage, an approach for construction of planar mechanisms via an educational robotic kit has also been utilized. The prototypes of the adjustment systems and mechanical force/torque generators have been connected to the constructed planar mechanisms via the educational robotic kit. Then, the actual performances of the systems have been tested by measuring the energy consumption of the actuators. It has been detected that the test results do not sufficiently match the expected results due to effects of the encountered practical problems.