كفاءة الكاميرا الحرارية تحت ظروف الطقس الرديء والهدف المتحرك في مدينة كربلاء المقدسة

Efficiency of Thermal Camera under Bad Weather and Moving Target Conditions in Holy Karbala City

Abstract

Thermal imaging cameras are widely used in military applications for their night vision capabilities at different observation ranges. The efficiency of the thermal camera depends on the image quality or detecting and recognizing the target. In this work, a mathematical model that programed in Mathcad to verify the efficiency of the thermal camera (PT-602CZ HD) when the object is in motion at different speeds. The intensity distribution in thermal images is calculated by using the transfer function. Bar Spread Function (BSF) solved at two cases with and without linear motion of the object. The values of the linear motion factor of the object were calculated with different velocities (40,60,80.100, and 120) Km/h. The intensity distributing of the thermal image evaluated for different ranges (150 to 4500) m. The results show that the target can be detected and distinguished in the ranges (150, 300,500) m but the target detects only in the ranges (750) m. If the range of the moving target is larger than 750m the detection also occurs but at a different resolution, if the range is reached 2500 m and more the thermal imaging is impossible for this type of thermal camera. Compare the theoretical results of intensity degraded of the thermal image with the images of moving objects captured practically by the thermal camera at 40 Km/h velocity of the object in the Ain Al-Tamer area for the holy Karbala city. Detection of a target is influenced by the case of the weather conditions. Atmospheric transmission of the infrared band at (5, 10) μm is evaluated at different Visibility (200,300,400,500,600,700,800) m with the presence of fog at different ranges (200,300,400,500,600,700,800) m in the same area of study, and the effective range is investigated. Experimentally, thermal images are captured by the thermal camera at various ranges (200,300,400,500) m at visibility 400 m. The transmission of infrared radiation is affected by atmospheric conditions such as fog and the transmission depends on the concentration of particles suspended in the atmosphere. Both range and fog are a strong impact on thermal images captured by the thermal camera. The atmospheric transition of 10 μm under foggy conditions is better than 5 μm. Therefore, the detection and recognizing of the object by the thermal camera with 10 μm is a favorite. The theoretical results agree with the experimental thermal images were taken in this case and the same area. Also, the detection of a target is influenced by air pollution such as dust (ambient particulate matter PM10). Calculation of the visibility (V) range with ambient particulate matter PM10 is performed. Atmospheric Transmission of the Infrared Radiations (ATIR) with 10 μm is evaluated at different concentrations of particulate matter PM10 (10, 20, 30, 40, 50 ) μg/m3 recorded by Iraq Meteorological Organization and Seismology in Ain Al-Tamer area for the holy Karbala city, Iraq. The results show that the PM10 concentration significant affects the resolution power of images in thermal imaging. The PM10 concentration in the study area has a slight influence on the thermal image.