چكيده به لاتين
A mobile manipulator represents a combination of a manipulator arm and a mobile base, which naturally integrates the characteristics of a fixed-arm manipulator (for example, the manipulation capabilities), and the mobility of a mobile robot. The mobile manipulator has many possible applications in the transportation sector, stemming from a significant increase in the workspace of the robot. However, the applications of these manipulators suffer, as their weight severely impacts both the stability of the robot and its overall performance. An effective method of addressing this issue is with the use of a flexible arm instead of a rigid arm, which can reduce the overall weight of the robot. Still, the main issue is to determine the manipulator's dynamic payload capacity at the same time that stability conditions, robot dynamics, and motor torque saturation limits are considered. To improve the performance and mobility of the manipulator, along with the capability to adjust the height of the mobile base, a wheeled-crawler base is used. The wheeled base offers superior performance capabilities on a smoother and flatter ground, while the crawler base provides more advantages on more uneven surfaces. So in order to achieve optimal performance on both smooth and uneven surfaces, this research used a hybrid wheeled-crawler base, considering it possesses characteristics that enable rapid and effective re-positioning of the manipulator. This research specifically addresses the examination and determination of the dynamic payload capacity of a flexible wheeled-crawler manipulator. Also, simply because robot control under unstable conditions is also very important, this research also looks at advanced control methodologies for such robots that have been thoroughly reviewed. All the research associated with wheeled-crawler manipulator within this research was developed based upon the wheeled and crawler robot established in the Robotics Laboratory of the Faculty of Mechanical Engineering of Iran University of Science and Technology. The robot is designed with four single-link legs, each of which has a separate drive wheel, which connects to the robot's body through four independent servomotors. The manipulator is a flexible multi-link manipulator that is mounted to the top of the robot's body. In this research we achieve to a best optimization in 3-case study that used in chapter5; in first method we achieve to 43% and in second method we achieve to 36 % increase of load carrying ability at manipulator’s end-effector (in average). This increase has been made by taking into account the conditions of stability and not exceeding the torques and forces on the joints, respectively, from the saturation limit of torque and force. In addition, in the continuation of our work, we were able to optimize the routing for two three-dimensional points in such a way that the difference between the torques applied to both joints of the manipulator is the smallest, so that the manipulator can have the maximum load carrying capacity. Finally, by using the genetic algorithm, we made the optimization based on which we were able to obtain the physical parameters of the manipulator such as mass, length and moment of inertia, as well as the parameters related to flexibility such as spring rate and damping coefficient in such a way that the maximum carrying capacity Pay the load.
