###### Abstract  
The increasing threat of explosives is a serious issue affecting socio-economy of many countries at multiple levels, such as public security, unused arable land, closing of trade routes, isolation of villages, and these act as a hindrance in the development of the country. Activities using explosives have increased in the last two decades making it a global threat that is challenging humanity. In this study, different chemicals such as Ammonium Nitrate (AN), Trinitrotoluene (TNT) and C4 along with soil as the background material were used for trace detection. The aim of this study was to determine an altitude for the sensor and to identify the minimum mapping size of the chemical at which the model can achieve 70% accuracy. To determine the altitude and minimum size of the chemical that can be detected in the acceptable range of accuracy, several experiments were performed in real ground conditions. This study focuses on the applicability of the proposed method in the real world. In the first set of experiments, the altitude of the sensor was varied from 40 cm to 150 cm and the accuracy of the model was determined. From the analysis, it was found that the model achieved more than 75% accuracy at an altitude of 90 cm with an image overlap of 70%. In the second set of experiments, the minimum size of chemical sample was varied from 0.25 cm to 1 cm. The accuracy of the model was more than 70% when the minimum sample size was 0.5 cm or greater. For various altitude determined, the speed of the vehicle was calculated. Therefore, to implement hyperspectral imaging system on the unarmed vehicle for real application, the suggested altitude and speed of the sensor should be around 90 cm and 10.5 cm/s at which detection limit would be equal or more than 0.5 cm with accuracy greater than 70%. hyperspectral imaging; trace detection; minimum mapping +
Footnote †: journal: Applied  
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**[PERSON]. [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON] Influence of Altitude and Image Overlap on Minimum and Image Overlap on Minimum Mapping Size of Chemical in Non-Destructive Trace Detection**  
agriculture, but a mixture of ammonium nitrate and fuel oil, in the ratio of 94:6, results in an explosive which is used widely. This type of bomb is gaining a lot of popularity as it can be manufactured using commonly available material at home [1; 2; 3; 4; 5; 6; 7]. In recent years, across the globe some major terrorist attacks were noticed in Pakistan, Brussels, Nigeria (2016), Paris (2015), Boston (2013) in which IED were widely used. IED is becoming an ideal weapon for spreading terrorism due to its special features like ease of manufacture at low cost and it can be designed in various sizes and forms making it difficult to be detected. Large number of conflicts are taking place across the world, particularly in a number of war zones. This is a serious issue that is affecting socio-economy of many countries like public security, unused arable land, closing of trade routes, isolation of villages. Such problems act as a hindrance in the development of the country. These problems motivate the government and research community to develop techniques for fast and accurate detection of explosives. Trace detection of explosives are usually achieved using several methods like electrochemical sensors, bio sensors and optical sensors. Most of these methods involves heavy, non-portable and complex instruments due to which analysis is not performed at the crime location or bomb sites making them not suitable for field applications [8; 9]. Due to this forensic science and defense scientist are interested in developing detection technology which is non-destructive, portable with high sensitivity and selectivity, has ability to identify traces of chemicals in large background [10; 11].