About: Prismatic joint is a research topic. Over the lifetime, 519 publications have been published within this topic receiving 7290 citations.
Papers published on a yearly basis
TL;DR: In this paper, a detailed study of the singular configurations of 3-DOF planar parallel mechanisms with three identical legs is presented, where only prismatic and revolute joints are considered.
Abstract: This paper presents the results of a detailed study of the singular configurations of 3-DOF planar parallel mechanisms with three identical legs. Only prismatic and revolute joints are considered. From the point of view of singularity analysis, there are ten different architectures. All of them are examined in a compact and systematic manner using planar screw theory. The nature of each possible singular configuration is discussed and the singularity loci for a constant orientation of the mobile platform are obtained. For some architectures, simplified designs with easy to determine singularities are identified.
••01 Jan 1996
TL;DR: A three degree-of-freedom manipulator that has a fairly large translational workspace is presented and both the direct and inverse kinematics are investigated.
Abstract: A three degree-of-freedom manipulator that has a fairly large translational workspace is presented. The mechanism consists of a fixed base, a moving platform, and three extensible limbs. Each limb consists of a prismatic joint and two universal joints connecting the moving platform to the fixed base. Both the direct and inverse kinematics are investigated. The inverse kinematics problem yields two equal and opposite limb lengths for each limb while the direct kinematics problem is reduced to a second-degree polynomial in one unknown. Further, the workspace and singular conditions of the manipulator are discussed.
••07 Aug 2002
TL;DR: It is emphasized that the precise modeling of a flexure hinge is significant to guarantee the positional accuracy of parallel micromechanisms using Flexure hinge.
Abstract: Flexure hinge has been commonly used as a substitute for mechanical joints in the design of micropositioning mechanisms. However, inaccurate modeling of flexure hinges deteriorates the positioning accuracy. In this paper, a planar 3-DOF parallel-type micropositioning mechanism is designed with the intention of accurate flexure hinge modeling. For this, a preliminary kinematic analysis that includes inverse kinematics, internal kinematics, and analytic stiffness modeling referenced to the task coordinate is presented. First, the revolute type of 1-DOF flexure hinge is considered. The simulation result based on the finite element method, however, is not coincident to the analytic result. This is due to the minor axial elongation along the link direction that keeps the mechanism from precise positioning. To cope with this problem, a 2-DOF flexure hinge model that includes this additional motion degree as a prismatic joint is employed in part, and additional actuators are added to compensate for the motion of this new model. On the basis of this model, the positional accuracy is ensured. The effectiveness of this accurate model is shown through both simulation and experimentation. This paper emphasizes that the precise modeling of a flexure hinge is significant to guarantee the positional accuracy of parallel micromechanisms using flexure hinge.
TL;DR: In this paper, a planar polysilicon mechanism incorporating lower and higher kinematic pairs (or joints) was described, which is compatible with silicon microfabrication technology.
Abstract: The integrated fabrication of planar polysilicon mechanisms incorporating lower and higher kinematic pairs (or joints) is described. The two lower kinematic pairs (revolute and prismatic) commonly used in macrorobotic systems are compatible with silicon microfabrication technology. The mechanisms are fabricated by surface micromachining techniques using polysilicon as the structural material and oxide as the sacrificial material. Turbines with gear and blade rotors as small as 125 mu m in diameter and 4.5 mu m in thickness were fabricated on 20- mu m-diameter shafts. A clearance as tight as 1.2 mu m was achieved between the gear and the shaft. Gear trains with two or three sequentially-aligned gears were successfully meshed. A submillimeter pair of tongs with 400- mu m range-of-motion at the jaws was fabricated. This structure incorporates a single prismatic joint and two revolute joints, demonstrating linear-to-rotary motion conversion. >
TL;DR: The Cartesian Parallel Manipulator (CPM) as mentioned in this paper consists of a moving platform that is connected to a fixed base by three limbs and each limb is made up of one prismatic and three revolute joints and all joint axes are parallel to one another.
Abstract: This paper introduces a new 3-DOF translational parallel manipulator named the Cartesian Parallel Manipulator (CPM). The manipulator consists of a moving platform that is connected to a fixed base by three limbs. Each limb is made up of one prismatic and three revolute joints and all joint axes are parallel to one another. In this way, each limb provides two rotational constraints to the moving platform and the combined effects of the three limbs lead to an over-constrained mechanism with three translational degrees of freedom. The manipulator behaves like a conventional X-Y-Z Cartesian machine due to the orthogonal arrangement of the three limbs. Two actuation methods are analyzed. However, the rotary actuation method is discarded because of the existence of singularities within the workspace. For the linear actuation method, there exists a one-to-one correspondence between the input and output displacements of the manipulator. However, each limb structure is exposed to a relatively large moment about an axis perpendicular to the prismatic joint axis. In order to compensate for this shortcoming, a method to maximize the stiffness is suggested. Finally, a numerical example of the optimal design is presented.Copyright © 2002 by ASME
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