Flexible parallelogram mechanism based force sensor realizing two-stage force resolutions

Abstract

The invention discloses a flexible parallelogram mechanism based force sensor realizing two-stage force resolutions. The force sensor comprises a substrate, an upper cover board, a grating displacement sensor, a probe and a grating installation board, wherein the fiber bragg grating displacement sensor is installed in a long groove on the upper cover board; the upper cover board is fixed on the substrate by surrounding bolts; gaps exist between the left sides as well as the right sides of the upper cover board and the substrate; and one end of the probe passes through a via hole on a front board of the substrate and then is installed in a threaded hole of a tail end platform on the substrate. The force sensor has the following advantages: two groups of flexible parallelogram linear motionmechanisms are machined on the substrate by adopting wire cut electrical discharging machining and are symmetrically arranged to ensure high-precision linear motion of the middle platform, namely reducing the parasitic error of the mechanisms; and meanwhile, as a sensitive structure of the force sensor, the substrate is a part and dispenses with assembly, thus effectively avoiding such problems caused by assembly in the traditional force sensors as friction, gaps and the like. The sensor can effectively realize two-stage force resolutions which can not be realized by the traditional force sensors.

Description

technical field [0001] The present invention relates to a force sensor, more particularly, to a two-stage force resolution sensor based on a flexible parallelogram mechanism. Background technique [0002] During the thermal imprinting process of nanoimprinting, it is necessary to monitor the imprinting force. When the embossing head is close to the substrate, it can be monitored by the force sensor to judge whether the embossing head has been aligned, and perform corresponding calibration work. At this time, the embossing force is only a few Newtons; The head is completely pressed against the substrate, and the imprinting force at this time can reach hundreds or even thousands of Newtons. If a traditional uniaxial force sensor is used, different sensors need to be replaced in the above two processes, which will cause problems such as recalibration, which will greatly affect the accuracy of nanoimprinting. [0003] Another example is during the tensile strength test of meta...

AI Technical Summary

Problems solved by technology

[0008] (1) Existing force sensors cannot achieve two-level or even multi-level force resolution, and their measurement range is limited by resolution

In the case of multi-level force resolution requirements, it will not be able to meet the measurement requirements;

[0009] (2) The output signal of the existing force sensor is a weak analog signal, which is greatly affected by environmental noise;

[0010] (3) The accuracy and resolution of existing force sensors are limited by the force measurement range

That is, when the accuracy and resolution of the sensor increase, the measuring range of the sensor decreases and vice versa

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