چكيده به لاتين
Distance measurement is a research field with a variety of different applications. Among different methods, geometric distance measurement is a precise and well-tested approach based on geometric relationships and calculations to determine the distance to a specific object. The advantages of this method are its simplicity, low cost in installation and setup, flexibility, and the ability to obtain highly accurate and precise data at short distances. In this research, the feasibility and construction of a sensor for one-dimensional distance measurement are considered. For the implementation of geometric distance measurement, a linear array sensor with serial communication capability and built-in analog-to-digital converter, plus an ARM-based STM32 microcontroller were used. Additionally, a 660nm laser and a suitable lens in visible range was employed. In order to record and analyze the results, an ST-232 UART to RS-232 converter were used for connection to a computer. Finally, programming was done in the Keil µVision software, utilizing hardware initialization libraries from CubeMX. Considering the relatively complex geometric relationships of the Scheimpflug geometric arrangement, optical simulation was first performed using Zemax Optic Studio software. For this purpose, numerical calculations consistent with available lenses were carried out, followed by defining an appropriate lens in the software and calculating the geometric variables through program optimization. Ultimately, the optical arrangement was constructed using the obtained variables and optical components. After the experimental optimization of the optical arrangement, a reference surface was connected to a manually translation stage equipped with a micrometer screw, and the sensor's output data were compared to the observed values on the translation stage and a vernier caliper with 0.01 millimeter accuracy serving as a reference. To assess the accuracy of the sensor's performance, the fitted output was compared to the readings of similar industrial sensors. A maximum error of 50µ± was recorded within a ten millimeter range. This error is acceptable considering the cost-effectiveness of the sensor and the low cost of the optical arrangement, making it a competitive specimen compared to similar industrial sensors.
