FPGA-based dynamic motion decoding trigger

Abstract

The invention relates to an FPGA-based dynamic motion decoding trigger for connecting a control system and an acquisition system. The FPGA-based dynamic motion decoding trigger is composed of an FPGA module, an input signal level conversion circuit, a DA circuit and a pulse optical coupler conversion circuit. In the experiment, a position signal of a model is inputted into the FPGA module; the FPGA module parses the position information of the model according to a designed logic program; and the information is outputted to the acquisition system by the DA circuit in an analog quantity mode. And the FPGA module outputs a pulse signal with a certain frequency or at a fixed position according to the experiment requirement; and the signal uses a model moving position set in advance as the starting point to collect a determination signal. The pulse signal is outputted to the acquisition system; and the acquisition system uses the signal as an external interrupt signal and collects aerodynamic data and model position data synchronously. The trigger has advantages of high data accuracy, high multiplicity and efficiency, and good stability.

Description

technical field [0001] The invention relates to an FPGA-based dynamic motion decoding trigger. Background technique [0002] Dynamic experiments are an important part of wind tunnel experiments. Compared with conventional static experiments, dynamic experiments can obtain experimental data that cannot be obtained by static experiments, such as dynamic derivative experiments, large-scale oscillation experiments, and rotating balance experiments. In the dynamic experiment, it is necessary to obtain the aerodynamic data during the movement of the model, and the data density is high, and the data must match the position of the movement of the model, that is, it is collected synchronously. At present, the common acquisition method is that the acquisition system uses its own clock as the reference, and collects aerodynamic data at the frequency required by the experiment. For example, the model movement frequency is 1Hz, and it is required to collect 240 sets of data per cycle. In...

AI Technical Summary

Problems solved by technology

At present, the common acquisition method is that the acquisition system uses its own clock as the reference, and collects aerodynamic data at the frequency required by the experiment. For example, the model movement frequency is 1Hz, and it is required to collect 240 sets of data per cycle. In this way, the acquisition cycle of the acquisition system should be set to 1 / 240s. Most of the systems run on the Windows platform, and the acquisition period with high precision requirements is difficult to achieve. For the situation where it is desired to collect multi-period data, the experimental data will not correspond to the beginning and the end, resulting in the inability to process the experimental data. In addition, the aerodynamic data needs to be consistent with the model position Synchronous acquisition, the common acquisition system collects the aerodynamic data and the position signal output by the control system at the same time, it is difficult to ensure synchronization

Images