Design Of A Light Weight6R Bio-sampling Manipulator: Theory, Methodology And Application

This dissertation presents a complete theoretical package for the design of a lightweight6R articulated manipulator to meet the demand of sampling and detection inthe highly pathogenic biological contamination areas. The following contributionshave been made.(1) A method for the type synthesis of the6R manipulators having orthogonaljoints is presented by minimizing the number and order of the dimensional parametersto prevent the singularity represented by the nullity of the determinant of the Jacobian.Consequently, an optimized architecture is achieved from six possible candidates.(2) The forward and inverse displacement, velocity and acceleration analysesare carried out by means of screw theory and Lie algebra. A method for trajectoryplanning is investigated for achieving continuity of pose and their derivatives of theend-effector. It has been shown that these models are compact in form and easy toprogram in comparison with the influence coefficient method. Meanwhile, thenormalized index is also proposed to evaluate the kinematic performance of themanipulator.(3) A method to determine the envelop of the reachable workspace of themanipulator is proposed by considering the joint limits. Through an in-depthdiscussion of the influence of the dimensional parameters on the workspace, thedimensional synthesis problem is investigated by minimizing a dimensionlessconditioning index represented by the characteristic length, resulting in a set ofoptimized dimensional parameters that enable a good kinematic performance to beachieved within the entire workspace.(4) By means of Lagrange’s formulation, the rigid body dynamics is modeledand the inertial effects of various moving components on the driving torques areinvestigated. The results may provide the designers with an informative guidance forthe determination of servo motor specifications.(5) A prototype of the manipulator is designed and developed to demonstrate the overall process for the biological contamination detection.The outcomes of this dissertation are very useful for the development ofbio-sampling devices to ensure the safety of medical practitioners and to promote thebiological anti-terrorism capability of military forces.