Laser Interferometer Vibration Mapping with Rotary Object Scanning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing non-contact vibration measurement methods using laser interferometers are time-consuming and require complex setups, such as industrial robots, which necessitate safety measures and additional time for repositioning the interferometer at each measurement point.
Innovation Solution
A method and device utilizing a rotary device, such as a turntable, to position the object, combined with a laser interferometer and beam direction units, allowing the interferometer to remain stationary while measuring points are reached through rotational scanning, establishing a common reference system without the need for repositioning, and enabling non-contact vibration data acquisition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the laser interferometer is repositioned at each measurement point to achieve comprehensive coverage, then measurement completeness is improved, but measurement time and device complexity increase
Solution Approach 1:
The patent applies the dynamics principle by making the object rotate dynamically during measurement. Instead of repositioning the stationary interferometer, the object is rotated on a rotary device to bring different measurement points into the interferometer's fixed field of view, enabling comprehensive coverage without time-consuming repositioning operations.
Solution Approach 2:
The patent transitions from a spatial repositioning approach to a temporal scanning approach. By rotating the object through different angular positions, the system scans across multiple measurement points in the angular dimension while the interferometer remains stationary, effectively mapping the object surface without physical movement of the measurement device.
2Measurement precision
If the laser interferometer is repositioned at each measurement point to achieve comprehensive coverage, then measurement completeness is improved, but device complexity and safety requirements increase
Solution Approach 1:
The patent extracts the repositioning function from the interferometer system and transfers it to the object mounting device. The interferometer remains a simple stationary unit, while the rotary device handles the complexity of positioning and scanning across different measurement points, simplifying the overall measurement system architecture.
Solution Approach 2:
The rotating object essentially positions itself for measurement by its rotation, eliminating the need for complex external positioning mechanisms. The object's rotation automatically brings different surfaces into the interferometer's fixed measurement zone, making the system self-positioning without requiring sophisticated control systems.
3Productivity
If multiple measuring beams are used to measure from different spatial directions simultaneously, then measurement efficiency is improved, but device complexity increases
Solution Approach 1:
The patent makes the single interferometer universal by combining it with a rotary device that can orient the object in multiple directions. The interferometer performs the same measurement function at different angular positions, effectively becoming a multi-directional measurement system without requiring multiple separate interferometers or complex beam steering mechanisms.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Facilitates rapid and simple non-contact vibration measurement by eliminating the need for mechanical repositioning of the laser interferometer, reducing setup time and safety complexities, and allowing for efficient data acquisition and visualization in an object-specific coordinate system.
Implementation Method 1
The vibrational motion of the object's surface causes a Doppler shift in the frequency of the light reflected or backscattered from the surface
Implementation Method 2
a laser interferometer, usually a laser Doppler vibrometer, is used, with which each measurement point on the object is illuminated with coherent laser light
Implementation Method 3
By means of a beam direction control unit for each measuring head, the measuring beam or the multiple measuring beams of the laser interferometer can be changed in its direction
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The invention relates to a method and a device for non-contact vibration measurement of an object 1, comprising a rotating device 4 rotatable about a rotary axis 7 for positioning the object 1, a laser interferometer 2 whose measuring beam 13 can be changed in direction by means of a beam direction unit 22, and an evaluation unit 16 for determining the measuring points 14, assigning the vibration data from the laser interferometer 2 to the measuring points 14, and evaluating the vibration data, wherein the evaluation unit 16 cooperates with a control unit 12 to successively direct the measuring beam 13 to a plurality of predefined measuring points 14 on the object 1 by means of the beam direction unit 22.The control unit 12 is also configured to rotate the rotary device 4 at least once by a predetermined angle φ around the axis of rotation 7, or to detect such a rotation by measuring the angle, after which it successively directs the at least one measuring beam 13 onto a plurality of predefined measuring points 14 on the object 1. An output unit 17 then outputs the evaluated vibration data in correlation with the measuring points 14, preferably in an object-related coordinate system 19. Before the measurement, a spatial relationship is established between the laser interferometer 2, the axis of rotation 7, and the object 1.