Overall Design And Key Issues Study Of Mechanical Properties Nondestructive Testing Prototype Of The Full-Size Wood Composite Panels

China is a big country of wood-based composite panels production, ranking first in the world production, But not the powerful country. To make our country transform from the largest producer of wood-based composite panels to powerful producing country, the way to improve product quality testing is one of the measures to be taken. The mechanical properties of the wood-based composite panels are the important parts of the quality of the products, but China has not testing techniques, methods or equipment which are non-destructive, rapid and suit for testing the mechanical properties of full-scale wood-based composite panels yet.The main work of this paper is to develop a non-destructive testing equipment which is based on the principle of free vibration,it will be used to test the mechanical properties of full-scale wood-based composite panels. The main work is as the follows.(1) Designed the structure project of the prototype of testing the mechanical properties of full-scale wood-based composite panels, which has been divided into two components prototype mechanical structure and control system. In the mechanical design, using a modular design and bolt, pin positioning connections, so the prototype would be easy to remove and transport.(2) Studied and designed the vacuum system which would be used to take the full-scale wood-based composite panels in the testing prototype, built the mechanical model of the vacuum chuck in the moving process and analyzed the impact of factors that can affect the suction. Designed the vacuum circuit and the blow-air circuit which would break the vacuum when releasing the sheets.(3)Did the static analysis of prototype rack and the car in the position which has been detected by using the finite element analysis software ANSYS Workbench and did the modal analysis for rack.(4) Designed the excitation apparatus of vibration and did the tests for panels. Find the laser sensor is preferable to be the sensor which would be used to collect the vibration signal of wood-based composite panels; different pick-up location will affect the amplitude of the collecting vibration signal, but has no effect on the frequency of the vibration. Got the recommended values of four different excitation displacement for samples with different thickness.(5) Conducted the experiments of thickness measurement of wood-based composite panels based on the measure of non-contact using the laser sensor. It is feasible to use the two laser sensors(up and down)for the static and dynamic thickness measurement of wood-based composite panels.The processing installation commissioning results of testing prototype show that the full-scale wood-based composite panels mechanical properties of the nondestructive testing prototype to meet the requirements of the intended design, According to the existing detection function, the optimal installation position of the sensor is determined to guarantee the detection results., Through the experiment and solved the key problems in vibration measurement of the wood-based composite panel.