Multi-degree-of-freedom error measurement system for rotary axes and method thereof

Patent metadata

Field	Value
Publication number	US-11148245-B2
Application number	US-201816018436-A
Country	US
Kind code	B2
Filing date	Jun 26, 2018
Priority date	Apr 13, 2018
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

The present invention provides a multi-degree-of-freedom error measurement system for rotary axes and the method thereof. By producing a first ray, a second ray, and a third ray, the multi-facet reflector and the axicon disposed on an axis average line can receive the first, the second, and the third rays, respectively, for producing a reflective ray, a refractive ray, a first emitted ray, and a second emitted ray. Thereby, errors of the axicon in a plurality of degrees of freedom caused by shift or vibration of the axis average line, such as the x-axis radial error, the y-axis radial error, the axial error, the x-axis tilt error, the tilt error for the y-axis, and the angular alignment error for rotation can be measured.

First claim

What is claimed is:

1. A multi-degree-of-freedom error measurement system, comprising:
a plurality of light sources, producing a first ray, a second ray, and a third ray along one of an x-axis and y-axis;
a multi-facet reflector, disposed on an axis average line, said first ray incident to said multi-facet reflector, and said multi-facet reflector reflecting said first ray to produce a reflective ray;
an axicon, disposed on said multi-facet reflector, said second ray and said third ray incident to said axicon, forming a plurality of incident rays corresponding to a plurality of refractive vectors and one or more reflective vectors inside said axicon, respectively, and forming a first emitted ray and a second emitted ray from said incident rays while the rotation by said axicon is driven by an axis average line;
a plurality of two-dimensional optoelectrical sensors, disposed in the reflective direction of said multi-facet reflector reflecting said first ray and the light-emitting direction of said axicon outputting said first emitted ray and said second emitted ray, respectively, and the rotation of said axis average line driving said reflective ray, said first emitted ray, and said second emitted ray to form location variations on said plurality of two-dimensional optoelectrical sensors; and
an operational unit, disposed in a host to connect electrically to said plurality of two-dimensional optoelectrical sensors, executing statistics and operating a light path according to the initial vectors to read sensing results of said two-dimensional optoelectrical sensors while said host connected to said plurality of two-dimensional optoelectrical sensors, said plurality of refractive vectors, and said one or more reflective vectors of said first ray, said second ray, and said third ray to obtain a x-axis radial error, a y-axis radial error, an axial error, a x-axis tilt error, y-axis tilt error, and an angular alignment error for rotation as the axis average line rotates according to the location variations of said first emitted ray and said second emitted ray on said plurality of two-dimensional optoelectrical sensors.

2. The multi-degree-of-freedom error measurement system of claim 1 , wherein said operational unit calculates according to a ray tracing method and a first-order Taylor expansion equation to give said x-axis radial error, said y-axis radial error, said axial error, said x-axis tilt error, said tilt error for the y-axis, and said angular alignment error for rotation.

3. A multi-degree-of-freedom error measurement system, comprising:
a light source, producing an x-axis ray;
an axicon, disposed on an axis average line, said x-axis ray incident to said axicon along an x-axis and producing one or more refractions to produce an x-axis emitted ray while the rotation by said axicon is driven by said axis average line;
a pair of x-axis two-dimensional optoelectrical sensors, located in the emitting direction of said x-axis emitted ray for sensing said x-axis emitted ray; and
an operational unit, disposed in a host to connect electrically to said x-axis two-dimensional optoelectrical sensors to read sensing results of said two-dimensional optoelectrical sensors while said host connected to said plurality of two-dimensional optoelectrical sensors, operating an x-axis radial error and a x-axis tilt error according to the vector variations of said x-axis ray and said x-axis emitted ray on said pair of x-axis two-dimensional optoelectrical sensors.

4. The multi-degree-of-freedom error measurement system of claim 3 , wherein said operational unit calculates according to a ray tracing method and a first-order Taylor expansion equation to give said x-axis radial error and said x-axis tilt error.

5. A multi-degree-of-freedom error measurement system, comprising:
a light source, producing a y-axis ray;
an axicon, disposed on an axis average line, said y-axis ray incident to said axicon along a y-axis and producing one or more refractions to produce a y-axis emitted ray while the rotation by said axicon is driven by said axis average line;
a pair of y-axis two-dimensional optoelectrical sensors, located in the emitting direction of said y-axis emitted ray for sensing said y-axis emitted ray; and
an operational unit, disposed in a host to connect electrically to said y-axis two-dimensional optoelectrical sensors to read sensing results of said two-dimensional optoelectrical sensors while said host connected to said plurality of two-dimensional optoelectrical sensors, operating a y-axis radial error and y-axis tilt error according to the vector variations of said y-axis ray and said y-axis emitted ray on said pair of y-axis two-dimensional optoelectrical sensors.

6. The multi-degree-of-freedom error measurement system of claim 5 , wherein said operational unit calculates according to a ray tracing method and a first-order Taylor expansion equation to give said x-axis radial error and said x-axis tilt error.

7. A multi-degree-of-freedom error measurement system, comprising:
a plurality of light sources, producing an x-axis ray and a y-axis ray having different initial vectors;
an axicon, location on an axis average line and located at an intersection point of said x-axis ray and said y-axis ray, said x-axis ray and said y-axis ray incident to said axicon to produce a plurality of incident rays corresponding to a plurality of refractive vectors and one or more reflective vectors and to produce an x-axis emitted ray and a y-axis emitted ray for emitting while the rotation by said axicon is driven by said axis average line, and an angle formed between said x-axis emitted ray and said y-axis emitted ray;
a plurality of two-dimensional optoelectrical sensors, receiving said x-axis emitted ray and said y-axis emitted ray emerged from said axicon; and
an operation unit, disposed in a host to connect electrically to said plurality of two-dimensional sensors to read sensing results of said two-dimensional optoelectrical sensors while said host connected to said plurality of two-dimensional optoelectrical sensors, operating the vector variations of said x-axis ray and said y-axis ray and the vector variations of said x-axis emitted ray and said y-axis emitted ray on said plurality of two-dimensional optoelectrical sensors to give a x-axis radial error, a x-axis tilt error, a y-axis radial error, and y-axis tilt error.

8. The multi-degree-of-freedom error measurement system of claim 7 , wherein said operational unit calculates according to a ray tracing method and a first-order Taylor expansion equation to give said x-axis radial error, said x-axis tilt error, said y-axis radial error, and said tilt error for the y-axis.

9. A multi-degree-of-freedom error measurement method, comprising steps of:
producing a first ray, a second ray, and a third ray having different initial vectors;
driving said first ray, said second ray, and said third ray to output to a multi-facet reflector and an axicon on an axis average line, said multi-facet reflector producing a reflective ray according to said first ray, said second ray and said third ray forming a plurality of incident rays corresponding to a plurality of refractive vectors inside said axicon and one or more reflective vectors to form a first emitted ray and a second emitted ray while the rotation by said axicon is driven by said axis average line;
using a plurality of two-dimensional optoelectrical sensors to receive said reflective ray, said first emitted ray, and said second emitted ray, the rotation of said axis average line driving said reflective ray, said first emitted ray, and said second emitted ray to form vector variations on said plurality of two-dimensional optoelectrical sensors; and
using an opera

Assignees

• Univ Nat Chung Cheng

Inventors

• Liu Chien-Sheng
• Chen Yu-Ta
• Lin Yu-Xiang

Classifications

• G05B19/401 Primary

  characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes (G05B19/19 takes precedence) · CPC title

• B23Q17/2495

  using interferometers · CPC title

• G05B2219/37286

  Photoelectric sensor with reflection, emits and receives modulated light · CPC title

• B23Q17/2485 Primary

  using interruptions of light beams · CPC title

• B23Q17/249

  using image analysis, e.g. for radar, infrared or array camera images · CPC title