A method of real-time acquisition and alternate self-inspection of rail transit vehicle speed

Abstract

The invention relates to a real-time acquisition and alternative self-inspection method for rail traffic vehicle velocity. The method comprises the following steps: (1) performing filtering processingto an external sensor pulse signal and a testing self-inspection signal; (2)sending four ways of sensor signals and four ways of self-inspection signals into two channels of an FPGA through a state machine, so as to lead two groups of different pulses to enter two independent channels through changing of states after certain time; (3) for four ways of pulses entering into the two channels, respectively calculating the frequency values and direction values independently in each channel; and (4) through an CPU, judging the frequency values and direction values calculated, judging whether the expected frequency values and direction values of the self-inspections are identical, if yes, showing the internal circuit of the FPGA works normally, if no, the showing the internal circuit of the FPGAworks abnormally. The self-inspection to the acquired sensor pulse frequency values can be performed through the self-inspecting the pulses, so that the frequency values of a plurality of ways of signals can be accurately calculated, and the burden of the CPU can be lightened.

Description

technical field [0001] The invention relates to the field of rail transit, in particular to a method for real-time acquisition and alternate self-inspection of rail transit vehicle speeds. Background technique [0002] At present, some self-inspection methods and frequency acquisition mostly use some CPUs, single-chip microcomputers or DSPs for self-inspection and acquisition. Because they run according to the instruction cycle, even if there are multiple threads, they are not parallel in the true sense. When it is necessary to collect multiple signals at the same time, and to perform self-test on the collected signals, the real-time performance will be insufficient, and it will take up a lot of resources. In the field of rail transit, in order to reduce the burden on the CPU, the powerful parallel processing capability of FPGA can be used to accurately calculate the frequency value of multiple signals. And it can also be found in time when the internal registers of the FPG...

AI Technical Summary

Problems solved by technology

When it is necessary to collect multiple signals at the same time and perform self-test on the collected signals, the real-time performance will be insufficient and it will take up a lot of resources

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