Data Acquisition and Processing of Digital Level

摘要

This paper introduced the principle of digital level. Using the linear CCD to substitute the eyes of people, it realize to automatically measure by identifying the bar codes on the staff using microprocessor and image process technology. It described the design of hardware, software and staff in detail. The data acquisition system is accomplished after studying the data acquisition method of linear CCD output signals. The system acquires CCD output signals by controlling the timing sampling of A/D switcher. The data processing algorithm is achieved purposively after analyzing the data and waveform of CCD output signal. At first, the noise is dampen off with the filter algorithm combined with average-value filter and mid-value filter and the Signal Noise Ratio is increased. Then the edge signal of bar code image is chosen with the ledge detection algorithm. At last, the distance and the ahitude ware calculated by geometrical optics imaging and relative theory.