National Chung Shan Institute of Science and Technology

Chung-shan Institute of Science and Technology, Armaments, Bureau, Ministry of National Defense

Wei-Guo Chang

Yi-Yuh Hwang

Chin-Der Hwang

Li-Chung Liu

Chih-Ming Liao

Guang-Sheen Liu

Ting-Wei Chiang

Wen-Cheng Huang

Wen-Jen Lin

Ping-Ya Ko

Chih-ming Liao

An error compensation device includes at least one photographing module, a comparison module and a compensation module compensation module. The photographing module establish a space coordinate system relative to the object and comprises a first photographer and a second photographer which respectively photograph a first non-deformed laser speckle image on a first surface and a second non-deformed laser speckle image on a second surface, the first surface differs from the second surface by an azimuth. The comparison module respectively compares the first non-deformed laser speckle image before and after the displacement with the second non-deformed laser speckle image to calculate a displacement value between the two surfaces. The compensation module controls the movement of the object according to the displacement value. The error compensation utilizes the displacement of the non-deformed laser speckle image to obtain the absolute error of the object and compensate the error.

Error compensation device and error compensation method

A measurement, calibration and compensation system for machine tool includes a first positioning base; two first speckle image sensors for sensing speckle positions of an object holding unit at a first XY plane and a first XZ plane of the first positioning base before and after the machine tool is started for machining; a second positioning base; two second speckle image sensors for sensing speckle positions of a cutter holding unit at a second XY plane and a second YZ plane of the second positioning base before and after the machine tool is started for machining. Thus, the thermal expansion at all axes of the machine tool can be measured in a simplified and low-cost way, and the absolute positioning coordinates of all axes of the machine tool can be calibrated in real time to avoid reduced positioning accuracy due to the thermal expansion of the multi-axis machine tool.

Measurement, calibration and compensation system and method for machine tool

The present invention mainly provides a precision calibration method for being applied in a high-precise rotary encoder system, wherein the primary technology feature of the precision calibration method is that: using a laser speckle image capturing module to capture N frames of laser speckle image from an optical position surface of a rotary encoding body, and then using image comparison libraries and particularly-designed mathematical equations to calculate N number of image displacements, so as to eventually calculate N number of primary variation angles and sub variation angles corresponding to the N frames of laser speckle image. Therefore, after the rotary encoding body is rotated by an arbitrary angle, an immediate angle coordinate can be precisely positioned according to the primary variation angles, the secondary variation angles and the N number of image displacements.

Precision calibration method for high-precise rotary encoder

A quick subpixel absolute positioning device and method are introduced. The method includes the steps of (A) capturing a real-time speckle pattern of a target surface; (B) providing a coarse-precision speckle coordinate pattern and a plurality of fine-precision speckle coordinate patterns, wherein the coarse-precision speckle coordinate pattern and the fine-precision speckle coordinate patterns include a coordinate value; (C) comparing the real-time speckle coordinate pattern with the coarse-precision speckle coordinate pattern by an algorithm and then comparing the real-time speckle coordinate pattern with the fine-precision speckle coordinate patterns to obtain a coordinate value, wherein each said coarse-precision speckle coordinate pattern corresponds to a set of fine-precision speckle coordinate patterns, and the fine-precision speckle coordinate patterns are obtained when the coarse-precision speckle coordinate pattern is captured again and then captured repeatedly according to a fixed fine-precision displacement distance. Accordingly, the subpixel positioning is attained by quick comparison and manifests high precision.

Device and method of quick subpixel absolute positioning

An actuating apparatus includes a motion driving module rigidly coupled to a platform, a working stage driven by the motion driving module to move relative to the platform, a speckle image capturing module rigidly coupled to the working stage and capable of capturing a speckle image of a sub-region of a reference region of the platform, and a control module operable in a positioning mode, where the control module obtains a current position of the working stage in a coordinate system associated with the platform based on a comparison between the captured speckle image and reference speckle image information that is associated with and unique to the reference region, and controls the motion driving module to drive the working stage toward a target position in the coordinate system based on a difference between the current position and the target position.

Actuating apparatus, actuating system and method for actuating a working stage to move relative to a platform with high-precision positioning capability

Growing community of inventors

Taoyuan, Taiwan

Wei-Guo Chang