3D scanner and photogrammetry system in 3D inspection of Wind turbine blades
The structural dimensions of wind turbine blades directly affect the conversion efficiency of wind energy. Subtle deviations in the structure may cause the blades to resonate and reduce the service life of the blades. Therefore, three-dimensional reconstruction of the blade plays a crucial role in the study of finite element dynamic analysis and numerical simulation.
Q: Are the blades manufacturing of wind turbines complicated?
A: Obviously！ Fan blades are one of the key components of wind turbines. The current domestic fan blade manufacture is mainly secondary development on the basis of foreign product, so it can be seen that they can not be produced casually. It is necessary to design the blade model according to aerodynamics, reverse modeling the blade, numerically simulate the blade airfoil flow field, 3D inspection of blade blanks, and correct the deviation, etc., which all are the core links in the development and manufacturing process of the fan blade.
Q: Does those processes require a hand-held 3d scanner?
A: That’s right. In fact, the R&D, design, and production of many products are inseparable from 3D modeling. There are strict requirements of the fan blades in size and structure, so quality control during the manufacturing process is particularly important.
Q: What is the difficulty of 3D scanning in fan blades this time?
A: Fan blade is large in volume but high requirement in precision, so the difficulty is how to quickly acquire the three-dimensional data of the blade while ensuring high precision.
Fan blades are the most important components for wind turbines to convert wind energy. Its good size design is one of the important parameters to ensure stable and efficient operation of the blades. Therefore, the shape characteristics of the blade and the design of the precision have very strict requirements. Now the customer has produced a batch of blank blades of wind blades with a volume of about 6m×1m×0.4m. The customer needs to obtain the shape parameters of the blank, analyze the error by comparing with the standard parts, and then correct the size. The traditional measurement methods are difficult to detect, take a long time, and have a large human error. Therefore, an efficient and accurate three-dimensional detection method is being sought.
Customer: Manufacturer of large fan parts
Scanning object: Fan blade
Scanning device: HSCAN771 Handheld 3D Scanner & MSCAN Global Photogrammetry
Aim: Detecting the three-dimensional error of the blade blank and the standard part for blade dimension correction.
For large and medium-sized objects of large wind turbine blades, in order to improve the scanning rate and efficiency, Scantech uses HSCA771 with 7 bunches of crossed lasers (15 lasers in total) to scan it; As for accuracy, blade size up to 6m, the error will continue to accumulate during the 3D scanning process, and the larger the volume, the larger the cumulative error. Taking the fan blade as an example, the total error of the 6-meter-long blade can theoretically be up to 0.38 mm (the error is less than 0.38 mm due to the error ±0.02 mm ± 0.06 mm/m) with using HSCAN771 only.
Due to the high precision requirements of the blade, Technical staff of Scantach Technician use HSCAN 771 with MSCAN Global Photogrammetry System to scan, the maximum error is reduced to 0.17mm, the accuracy can be increased by 67%, and the volume error is greatly reduced.
Partial fan blade
Device & Model: HSCAN771 Handheld 3D scanner & MSCAN photogrammetry system
3D scanning measurement process:
Step1: Mark reflective marking points and coding points, place the ruler. The position of the ruler should be connected with the whole code point.
Step2: The MSCAN global photogrammetry system captures the corresponding marker points and code points at various angles, and calculates the overall marker points to obtain marker point data.
Step3: Importing the Marking point into scanning software SCANVIEWER, scanning it by HSCAN771 Handheld 3D scanner. And save the data into .iges, .stl and other common formats
Step4: Digital model and scanning data are fitted and aligned for 3D detection and analysis.
Step5: Adjust and optimize the shape of the product based on the inspection data.
3D scanning results
3D scanning stl data
Comparison deviation report of detection
3D scanning working time
It takes 8 minutes to mark points.
It takes 15 minutes to scan.
It takes 5 minutes to generate inspection report.
28minutes in total.
HSCAN+MSCAN is perfect match for precision measurement of medium and large workpieces
The MSCAN global photogrammetry system is usually used for the measurement and localization of large objects. On the one hand, it can be used with HSCAN to effectively reduce the cumulative error during 3D scanning. On the other hand, the MSCAN system can be used for 3D measurement of medium and large workpieces individually to detect product size, geometric deformation and so on. The use of global photogrammetry in conjunction with handheld 3D scanners makes 3D reconstruction of medium to large objects no longer a problem.