Ball hinge capable of measuring spatial revolution angle and offset in three degrees of freedom

Abstract

The invention discloses a ball hinge capable of measuring a spatial revolution angle and offset in three degrees of freedom. A traditional ball hinge is complex in angle measurement way and difficult to ensure high measurement precision. Two arc-shaped sliding blocks of the ball hinge disclosed by the invention are connected with a sliding slot of a ball head through a rolling pair; two pin shafts fixed on the two arc-shaped sliding blocks are supported in a pin shaft hole in a ball socket base respectively; a ball head connecting rod is fixed with the ball head, and a supporting hole of an output rod is supported on the ball head connecting rod; a capacitance electrode array is arranged at the bottom of the sliding slot; four second capacitance electrode groups are arranged on the pin shafts; four third capacitance electrode groups are arranged on the ball head connecting rod; and capacitance sensing electrode pairs are arranged on inner sides of the arc-shaped sliding blocks, the hole wall of the pin shaft hole of a ball socket and the hole wall of the supporting hole in the output rod. The ball hinge disclosed by the invention can realize non-contact type detection of the spatial revolution angle and offset of the ball hinge; and furthermore, an algorithm is simple, and the precision is high.

Description

technical field [0001] The invention belongs to the technical field of measurement, and in particular relates to a ball hinge capable of measuring three-degree-of-freedom rotation angles and offsets in space. Background technique [0002] The ball joint is a commonly used three-degree-of-freedom mechanical joint. It has the advantages of compact structure, flexible movement and strong bearing capacity. It has become a key component in mechanical equipment such as parallel mechanisms, industrial robots (mechanical arms) and auto parts? For example , the parallel machine tool is a new type of CNC machining equipment, in which each branch chain is connected with the dynamic and static platforms through a hinge, the quasi-static error of the system accounts for about 70% of the impact on the accuracy of the machine tool, and the error of the spherical hinge aligns with the static error. Impact? Since the movement of the ball joint is limited by the joint clearance and structural...

AI Technical Summary

Problems solved by technology

[0003] The traditional angle measurement is mainly based on single-degree-of-freedom moving objects. There are usually methods such as mechanical angle measurement, electromagnetic angle measurement and optical angle measurement. The measurement object of the space rotation angle of the ball hinge is carried out around the center of the ball in a constrained ball socket. For a three-degree-of-freedom rotating spherical rotor, it is difficult to directly apply the traditional single-degree-of-freedom angular displacement detection method. Many researchers have proposed some new methods and mechanisms for related problems. At present, the motion position measurement of spherical rotors can be divided into three types according to the measurement methods: Contact and non-contact? Among them, the main representative of the contact measurement scheme is to use the slide rail bracket mechanism and three rotary encoders to realize the decoupling of the measurement structure, which is transformed into a single-degree-of-freedom measurement problem; the non-contact measurement structure is mainly Design based on the principles of optical sensors, vision sensors and Hall sensors, and realize decoupling measurement of multi-degree-of-freedom angular displacement from data processing?

[0004] However, the above-mentioned detection method needs to build a complex system, the processing of measurement data is difficult, and it is difficult to ensure high measurement accuracy. In addition, in practical applications, there are high requirements for installation space and working environment, and a large cost is required. , the study protocol has obvious limitations

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