Dynamic strain excitation method and device

Abstract

The invention discloses a dynamic strain excitation method and device, and belongs to the technical field of strain measurement. A piezoelectric stack is combined with a T-shaped beam to apply magnitude-controllable prestress to a giant magnetostrictive material rod, an alternating magnetic field is applied to the giant magnetostrictive material rod in an electromagnet mode to drive the giant magnetostrictive material rod to stretch out and draw back, and therefore, dynamic strain waveforms are generated on the side wall of the giant magnetostrictive material rod, and high-quality dynamic strain excitation is provided for a resistance strain gauge. A working mode in which the piezoelectric stack is combined with the giant magnetostrictive rod is used, the giant magnetostrictive rod generates dynamic strain excitation of sinusoidal waveform change, dynamic strain is obtained on the side face of the giant magnetostrictive rod through the electromagnetic elastic effect of the giant magnetostrictive rod, the piezoelectric stack generates a prestress value through the lever principle, and accurate magnitude regulation and control are conducted in a closed-loop negative feedback mode. Therefore, the loading and accurate control of the prestress when the giant magnetostrictive rod generates dynamic strain waveform excitation are realized.

Description

technical field [0001] The invention relates to a dynamic strain excitation method and device, and belongs to the technical field of strain measurement. Background technique [0002] The strain excitation device is the core of the strain gauge calibration. Usually, the strain value is generated by loading and driving the strain beam. There are many theoretical and technical research results, most of which focus on the generation of static strain and stress. It is difficult to generate dynamic strain. One of the difficulties is emphatically reflected in the realization of the dynamic strain excitation source. It has always been one of the technical choices to generate dynamic strain values ​​by using a vibrating table to load and drive the strain beam. Due to the need to drive the strain beam, the load on the vibrating table is relatively large, which limits the strain range and frequency range, which is difficult. Realize the excitation of larger range and wider frequency r...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problem that the load of the strain beam is too heavy when the dynamic strain is generated, resulting in the limited range and frequency range, the first technical problem to be solved in the dynamic strain excitation method and device disclosed by the present invention is: use the giant magnetostrictive material rod itself as Elastomers generate dynamic strain directly for large strain ranges and wide frequency ranges

Images