| Major industrial applications of parallel manipulators are airplane simulators, automobile simulators, in work processes, photonics/fiber alignment. They also become more popular in high speed, high-accuracy positioning with limited workspace, as micro manipulators mounted on the end effector of larger but slower serial manipulators as high speed/high-precision milling machines. Parallel robots are usually faster than traditional articulated robots, since the motors can be mounted on the base, thus saving weight. They are also stronger than serial robots because the end effector is connected to more links. However, parallel robots are usually more limited in the workspace; for instance, they generally cannot reach around obstacles. The calculations involved in performing a desired manipulation (forward kinematics) are also usually more difficult and can lead to multiple solutions.This thesis covers a study on kinematics and dynamic analysis of a new type of spatial three degree of freedom parallel manipulator, the background for structural synthesis of parallel manipulators is also given, the main point of interest for this manipulator, is its mobile platform which has to accomplish just two rotation about two perpendicular axes on the horizontal plan. The mechanical elements which are necessary for the construction of manipulators are introduced, the architecture of the mechanism is being composed of a mobile platform attached to the base through three legs each composed of three identical jointed serial linkages (comprised of universal-prismatic-universal). The prismatic joints lies on each leg are considered to be actuated.Kinematics analysis comprises forward and inverse displacement analysis. The basic kinematics equations for use of the manipulator are derived to analyze the position and the length of legs. Denavit-Hartenberg (D-H) convention was the main tool used. On the dynamics part, attention has been given on inverse dynamics problem using Euler formulation. |
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