Four-degree-of-freedom parallel mechanism

Abstract

The invention discloses a parallel mechanism. The parallel mechanism comprises a fixed platform, a movable platform, a first branch chain and a second branch chain. The first branch chain and the second branch chain are connected with the fixed platform and the movable platform respectively to form a spatial parallel closed-loop mechanism. Each of the first branch chain and the second branch chain comprises a first unit, a second unit and a first connecting piece, wherein the first unit and the second unit are rotatably connected through the first connecting piece, the first unit and the first connecting piece constitute a first mechanism, and the second unit and the first connecting piece constitute a second mechanism; the first mechanism is movably connected to the fixed platform; the second mechanism is rotatably connected to the movable platform, wherein the first mechanism moves in a first plane and has two degrees of freedom of translation; the second mechanism moves in a second plane and has two degrees of freedom of translation; the first plane is perpendicular to the second plane to each other. By virtue of linearly driving the first mechanism to move, three degrees of freedom of translation and one degree of freedom of rotation of the movable platform can be realized.

Description

Technical field [0001] The invention relates to a motion mechanism used in the field of robots, in particular to a four-degree-of-freedom parallel mechanism. Background technique [0002] The tandem SCARA robot has four degrees of freedom of motion, including translational degrees of freedom in the X, Y, and Z directions and rotation degrees of freedom around the Z axis. It is widely used in industrial fields such as handling, assembly, and welding, but its carrying capacity is The dynamic performance is poor, the inertia is large, the rigidity and precision are not high. Parallel mechanism is a closed-loop mechanism composed of multiple branch chains. Its unique structure makes this type of mechanism have higher dynamic response performance and easier to achieve high-speed and high-acceleration motion. Someone proposed a Delta three-degree-of-freedom spatial translational parallel mechanism, which has the characteristics of fast motion, accurate positioning, low cost, and high ...

AI Technical Summary

Problems solved by technology

Some people simplified the Delta mechanism into a planar Diamond mechanism, but there are only two degrees of freedom, and the function is relatively simple; a team has successively invented four-branched mechanisms such as H4, I4, Heli4, and Par4. The H4 parallel mechanism that can realize SCARA movement has been successfully commercialized. Typical representative products are such as the AdeptQuattro series, but this type of parallel mechanism has complex structure and complex kinematics characteristics; someone also proposed a four-degree-of-freedom single-action mechanism that can realize SCARA movement Platform parallel mechanism, the structure is relatively simple, but the working space is limited, the rotation angle is small, and there are multiple spherical joints, the processing is difficult, and the accuracy is difficult to guarantee

At present, the high-speed and few-degree-of-freedom parallel mechanisms used for high-speed grasping operations mostly have two degrees of freedom and three degrees of freedom, which are often difficult to meet the requirements of production lines; while the working space of four-degree-of-freedom parallel mechanisms used for high-speed grasping operations is limited. More complex, more singular configurations

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