Orthoglide型機構の幾何学的合成のための設計戦略
Design Strategies for the Geometric Synthesis of Orthoglide-type Mechanisms
直交3自由度パラレルマニピュレータOrthoglideについて、作業立方体サイズと速度伝達・可操作性などの性能要件からリンク長や関節限界を解析的に決める3つの設計戦略を提案し、パレート最適解となることを示した論文。
著者: Anatoly Pashkevich, Philippe Wenger, Damien Chablat
分類: cs.RO
原文アブストラクト
The paper addresses the geometric synthesis of Orthoglide-type mechanism, a family of 3-DOF parallel manipulators for rapid machining applications, which combine advantages of both serial mechanisms and parallel kinematic architectures. These manipulators possess quasi-isotropic kinematic performances and are made up of three actuated fixed prismatic joints, which are mutually orthogonal and connected to a mobile platform via three parallelogram chains. The platform moves in the Cartesian space with fixed orientation, similar to conventional XYZ-machine. Three strategies have been proposed to define the Orthoglide geometric parameters (manipulator link lengths and actuated joint limits) as functions of a cubic workspace size and dextrous properties expressed by bounds on the velocity transmission factors, manipulability or the Jacobian condition number. Low inertia and intrinsic stiffness have been set as additional design goals expressed by the minimal link length requirement. For each design strategy, analytical expressions for computing the Orthoglide parameters are proposed. It is showed that the proposed strategies yield Pareto-optimal solutions, which differ by the kinematic performances outside the prescribed Cartesian cube (but within the workspace bounded by the actuated joint limits). The proposed technique is illustrated with numerical examples for the Orthoglide prototype design.
