A Novel Approach To The Embodiment Design Of A Robotic System For Maximum Workspace

In the modern society, Personal Digital Assistant (PDA) such as laptops is indispensable device in our daily life. However, a PDA user often needs to adjust his/her posture to acquire a better access to the PDA for actions such as data entry and visual acquisition. This way of interaction between the PDA and user may be called passive adaptation of the user to the device. Obviously, such a passive adaptation may cause many types of repetitive injuries on users such as the cervical vertebra and lumbar strain. In this thesis, a new paradigm of adaptation, that is the device adaptive to the user, was proposed and studied. This paradigm may be called active adaptation.In order to realize the active adaptation approach, this thesis took the design of the orientation maneuver system (OMS) as an example. The goal of the study was to design an OMS and conduct workspace optimal design for maximum orientation space. There were three specific objectives defined for this thesis:(i) to study the kinematic mechanism or conceptual design for a maximum orientation space, (ii) to study the embodiment of the kinematic mechanism without loss of the workspace of the kinematic mechanism, and (iii) to design and validate an OMS of PDA for a maximum orientation space based on the results from (i) and (ii).The thesis took the 3-DOF spherical parallel robot (SPR) as an example for study. The optimization of workspace for the kinematic SPR was performed. Then, the three principles for the embodiment design of SPR were proposed to minimize the loss of workspace of the kinematic SPR. A GA-based algorithm to check the inference of bodies was developed. Finally, an example SPR system was designed, showing its improvement of the workspace in comparison with the other one in the literature.The major contributions of the thesis may be of two folds:First, the kinematic SPR was optimized based on two parameters, which were not explored by others in the field of kinematic design or conceptual design of SPR. Second, the embodiment design of SPR for the minimum loss of the workspace of the kinematic SPR was not discussed by others in literature, despite its importance to the workspace. The proposed principles are also applicable to general machine design at the embodiment design phase.