Forward Position Analysis of Parallel Mechanisms in Novint Falcon Haptic Device

The forward position solution (FPS) of any complex parallel mechanism (PM) can be solved through solving in sequence all of the independent loops contained in the PM. Therefore, when solving the positions of a PM, all independent loops, especially the first loop, must be correctly selected. The optimization selection criterion of the position analysis route (PAR) proposed for the FPS is presented in this paper, which can not only make kinematics modeling and solving efficient but also make it easy to get its symbolic position solutions. Two three-translation PMs are used as the examples to illustrate the optimization selection of their PARs and obtain their symbolic position solutions.

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Geometry and Position Analysis of a Novel Class of Hybrid Manipulators

23rd Biennial Mechanisms Conference: Robotics — Kinematics, Dynamics and Controls ◽

10.1115/detc1994-0300 ◽

1994 ◽

Author(s):

Change-de Zhang ◽

Shin-Min Song

Keyword(s):

Closed Form ◽

Degrees Of Freedom ◽

Parallel Manipulators ◽

Parallel Mechanisms ◽

Serial Manipulators ◽

Closed Form Solutions ◽

Position Analysis ◽

Hybrid Manipulator ◽

Load Carrying ◽

Inverse Position Analysis

Abstract This paper presents a novel class of hybrid manipulators composed of two serially connected parallel mechanisms, each of which has three degrees of freedom. The lower and upper platforms respectively control the position and orientation of the end-effector. The advantages of this type of hybrid manipulator are larger workspace (as compared with parallel manipulators) and better rigidity and higher load-carrying capability (as compared with serial manipulators). The closed-form solutions of the forward and inverse position analyses are discussed. For forward position analysis, it is shown that the resultant equation for the positional mechanism is an 8-th order, a 6-th order, a 4-th order, or a 2-nd order polynomial, depending on the geometry and joint types of the passive subchain, while for the orientational mechanism, it is an 8-th order, or a 2-nd polynomial depending on the geometry. For inverse position analysis, it is demonstrated that the positional and orientational mechanisms both possess analytical closed-form solutions.

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A Six Degree-of-Freedom Haptic Device Based on the Orthoglide and a Hybrid Agile Eye

Volume 2: 30th Annual Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2006-99065 ◽

2006 ◽

Cited By ~ 5

Author(s):

Damien Chablat ◽

Philippe Wenger

Keyword(s):

Degrees Of Freedom ◽

Degree Of Freedom ◽

Haptic Device ◽

Parallel Mechanisms ◽

Real Time Control ◽

Time Control ◽

Rotational Motions ◽

Six Degree Of Freedom ◽

Rotary Motor ◽

Three Degrees Of Freedom

This paper is devoted to the kinematic design of a new six degree-of-freedom haptic device using two parallel mechanisms. The first one, called orthoglide, provides the translation motions and the second one, called agile eye, produces the rotational motions. These two motions are decoupled to simplify the direct and inverse kinematics, as it is needed for real-time control. To reduce the inertial load, the motors are fixed on the base and a transmission with two universal joints is used to transmit the rotational motions from the base to the end-effector. Two alternative wrists are proposed (i), the agile eye with three degrees of freedom or (ii) a hybrid wrist made by the assembly of a two-dof agile eye with a rotary motor. The last one is optimized to increase its stiffness and to decrease the number of moving parts.

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