Kinematic Performance Measures and Optimization of Parallel Kinematics Manipulators: A Brief Review

This paper is concerned with the effects of actuation schemes on three measures of kinematic performance which depend upon a manipulator’s Jacobian matrix (namely, the minimum singular value, the manipulability, and the condition number). We begin by presenting a simple framework on how to incorporate actuator location and drive mechanisms in the kinematic model. Then, we redefine the performance measures using the new model. For each measure we derive properties relating its joint space to its actuator space description. Next we demonstrate that the choice of actuation scheme influences the size, shape, and direction of the velocity ellipsoid of the end-effector. Finally, we employ the above concepts in the design of a 2R planar mechanical arm. Its transmission ratios and drive mechanisms are selected in order to obtain good kinematic characteristics. We show that the choice of actuation scheme can be used to improve kinematic performance.

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Design of a 4-DoF (degree of freedom) hybrid-haptic device for laparoscopic surgery

Mechanical Sciences ◽

10.5194/ms-12-155-2021 ◽

2021 ◽

Vol 12 (1) ◽

pp. 155-164

Author(s):

Houssem Saafi ◽

Med Amine Laribi ◽

Said Zeghloul

Keyword(s):

Laparoscopic Surgery ◽

Degrees Of Freedom ◽

Haptic Device ◽

Haptic Interface ◽

Gravity Compensation ◽

Parallel Kinematics ◽

Dimensional Synthesis ◽

Parallel Chain ◽

Serial Chain ◽

Kinematic Performance

Abstract. This paper presents a novel kinematics architecture with 4 DoFs (degrees of freedom) intended to be used as a haptic interface for laparoscopic surgery. The proposed architecture is a result of an association of serial and parallel kinematics chains, with each one handling a part of the whole device DoF. The serial chain allows one to handle the translation and self-rotation and the parallel chain handles the two tilt motions, and this in a disjoint way as the natural gesture of the surgeon. The proposed hybrid-haptic device (HH device) benefits from the split DoF to ensure a good kinematic performance, large workspace, as well as gravity compensation. The kinematics study of the HH device is presented and followed by the optimal dimensional synthesis and the gravity compensation model.

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The Effects of Actuation Schemes on the Kinematic Performance of Manipulators

Volume 2B: 24th Biennial Mechanisms Conference ◽

10.1115/96-detc/mech-1147 ◽

1996 ◽

Author(s):

Ricardo Matone ◽

Bernard Roth

Keyword(s):

Performance Measures ◽

Condition Number ◽

Jacobian Matrix ◽

Kinematic Model ◽

Joint Space ◽

Singular Value ◽

End Effector ◽

Kinematic Performance ◽

Actuation Scheme ◽

Space Description

Abstract This paper is concerned with the effects of actuation schemes on three measures of kinematic performance which depend upon a manipulator’s Jacobian matrix (namely, the minimum singular value, the manipulability, and the condition number.) We begin by presenting a simple framework on how to incorporate actuator location and drive mechanisms in the kinematic model. Then, we redefine the performance measures using the new model. For each measure we derive properties relating its joint space to its actuator space description. Next we demonstrate that the choice of actuation scheme influences the size, shape, and direction of the velocity ellipsoid of the end-effector. Finally, we employ the above concepts in the design of a 2R planar mechanical arm. Its transmission ratios and drive mechanisms are selected in order to obtain good kinematic characteristics. We show that the choice of actuation scheme can be used to improve kinematic performance.

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Review article: Performance measures of parallel kinematics manipulators

Mechanical Sciences ◽

10.5194/ms-11-49-2020 ◽

2020 ◽

Vol 11 (1) ◽

pp. 49-73 ◽

Cited By ~ 2

Author(s):

Abdur Rosyid ◽

Bashar El-Khasawneh ◽

Anas Alazzam

Keyword(s):

Performance Measures ◽

Review Paper ◽

Dynamic Performance ◽

Review Article ◽

Extensive Review ◽

Parallel Kinematics ◽

Force Transmission ◽

Performance Indices ◽

Computation Cost ◽

Mathematical Expressions

Abstract. This extensive review paper, which involves 204 papers, discusses comprehensively a number of performance indices that are instrumental in the design of parallel kinematics manipulators. These indices measure the workspace as well as its quality including the distance to singularity, dexterity, manipulability, force transmission, accuracy, stiffness, and dynamic performance. After being classified, the indices are discussed in terms of some important aspects including definition, physical meaning soundness, dependency, consistency, scope of applicability, and computation cost. For the sake of completeness, some key mathematical expressions of the indices are provided.

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