Hand controller and wrist device
First Claim
1. A hand controller or wrist device comprising a base and a moveable portion moveable relative to said base, said moveable portion having a main longitudinal axis and an end point, a pair of pantographs each formed by a plurality of pivotably interconnected links arranged for pivotal movement in a plane, said planes being mutually perpendicular, means for pivotably mounting each said pantograph adjacent to one of its ends for rotational movement on its pivotal axis relative to said base in a direction substantially perpendicular to its plane and coupling means connecting each of said pantographs adjacent to its end remote from its one end to move said end point in a hemispherical path about a center point when said pantographs are pivoted on their said means for pivotably mounting, said pantographs defining a first and a second degree of freedom of said end point;
- said center point being defined by the intersection of said pivotal axes and said main longitudinal axis, an inner universal joint, said inner universal interconnecting a first inside element and a second inside element forming a pair of inside elements that define a third degree of freedom of said end point, said first of said inside elements including a pair of portions and means for translating axial movement substantially parallel to said main axis of one of said pair portions of said first inner element to rotational movement of a second portion of said pair of portions of said first inner element and vice versa while permitting relative rotational movement between said one and said second portions, said end point being connected to said one portion of said one of said second pair of elements and, means for mounting said second inside element for rotation about it axis relative to said base;
said coupling means connecting said pantographs to said one portion while permitting movement of said one portion relative to said pantographs.
1 Assignment
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Accused Products
Abstract
A compact four degrees of freedom parallel mechanism suitable for use as a hand control or wrist is provided that has backdrivability, is singularity free and has a large workspace and a large force reflecting capability. The structure is light but rigid, and the electric actuators are all placed on the ground or base and provide independent control of each degree of freedom. Each degree of freedom is connected to an actuator either directly or through a cable drive system. The first two degrees of freedom are created by two identical pantographs pivoted together on pivoted joints to define a hemispherical motion of an object (end point) about a center point (hemisphere center). The third and fourth degrees of freedom represent rotation and sliding motions of the object around and along the radius of the created hemisphere, respectively. The axes of these latter degrees of freedom are concentric, and these axes intersect with the axis of the pantographs pivoted joints at the hemispheric center.
132 Citations
20 Claims
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1. A hand controller or wrist device comprising a base and a moveable portion moveable relative to said base, said moveable portion having a main longitudinal axis and an end point,
a pair of pantographs each formed by a plurality of pivotably interconnected links arranged for pivotal movement in a plane, said planes being mutually perpendicular, means for pivotably mounting each said pantograph adjacent to one of its ends for rotational movement on its pivotal axis relative to said base in a direction substantially perpendicular to its plane and coupling means connecting each of said pantographs adjacent to its end remote from its one end to move said end point in a hemispherical path about a center point when said pantographs are pivoted on their said means for pivotably mounting, said pantographs defining a first and a second degree of freedom of said end point; -
said center point being defined by the intersection of said pivotal axes and said main longitudinal axis, an inner universal joint, said inner universal interconnecting a first inside element and a second inside element forming a pair of inside elements that define a third degree of freedom of said end point, said first of said inside elements including a pair of portions and means for translating axial movement substantially parallel to said main axis of one of said pair portions of said first inner element to rotational movement of a second portion of said pair of portions of said first inner element and vice versa while permitting relative rotational movement between said one and said second portions, said end point being connected to said one portion of said one of said second pair of elements and, means for mounting said second inside element for rotation about it axis relative to said base;
said coupling means connecting said pantographs to said one portion while permitting movement of said one portion relative to said pantographs. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
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Specification