# TYCOS: A Specialized Dataset for Typical Components of Satellites
## 3 The TYCOS Dataset
### Simulation of Multiple Operating Conditions  
Compared to existing datasets, the dataset proposed in this paper accurately simulates a space environment's illumination, satellite motion states, and satellite occlusion conditions. The details are as follows:  
Illumination conditions: To authentically replicate practical illumination conditions in space, the semi-physical acquisition system was situated in a darkroom. A sun simulator directed light onto the satellite model at an incident angle between 10\({}^{\circ}\) and 20\({}^{\circ}\). The sun simulator incorporated high-intensity LED light sources allowing for adjustments in brightness, irradiation coverage, and beam dimensions, thus accurately simulating the collimated, homogeneous, and spectral properties of natural solar radiation. However, in images, variations in brightness and darkness become conspicuous when sunlight falls on the satellite body and light reflected from the thermal insulation layer on the body's surface is projected onto the camera's imaging plane. Conversely, sunlight shining on a satellite's solar panels often results in overexposure, leading to extreme irradiation conditions, comprising dimmed illumination and heightened saturation. As illustrated in Figure 2, we classified illumination into three distinct categories: standard lighting, dim lighting, and elevated color saturation. Normal illumination indicates a clear satellite surface, free from shadows and uneven spots. Low illumination implies that shadows and darkened regions may obscure critical satellite components. In elevated color saturation conditions, conspicuous bright spots emerge on specific sections of the satellite, resulting in critical components in those areas becoming undetectable. The above illumination types are prevalent in space and significantly influence the accuracy of key satellite component detection. However, this aspect has often been overlooked in other published datasets.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline LED Bulb & T6 \\ Weight & 145 g \\ Source & one \\ Dimensions & 9.5 \(\times\) 6.2 \(\times\) 8.8 cm \\ \hline \hline \end{tabular}
\end{table}
Table 4: The parameters of the lighting device.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline Detector Signal & IMX250 \\ Pixel Size & 3.45 \(\upmu\)m \(\times\) 3.45 \(\upmu\)m \\ Target Surface Size & 2/3\({}^{\prime\prime}\) \\ Resolution & 2432 \(\times\) 2048 \\ Dynamic Range & 75.4 dB \\ Gain & 0 dB-20 dB \\ Exposure Time & 15 \(\upmu\)s 10 s \\ Frame Rate & 140 fps \\ \hline \hline \end{tabular}
\end{table}
Table 3: The main parameters of the MV-CH050.  
and the observing satellite significantly impacted the detection accuracy of key satellite components. However, this aspect has often been overlooked in other published datasets.  
Occlusion Status: In practical capture scenarios, a flyby stage exists in the motion states between the target satellite and the observing satellite. During the flyby stage, as illustrated in Figure 5, the observing satellite maneuvers around the target satellite along the positive or negative \(X\)-axis direction. Throughout this flyby, the observing satellite may capture images with the main body of the target satellite occl  
Figure 3: Examples of the satellite target in approaching and hovering states.  
resulting in the missed or failed detection of critical satellite components. To simulate the flyby stage, the camera was fixed at a distance of 0.5 m from the satellite to observe the flyby of the target. The captured images, exemplified using the BeiDou satellite, are depicted in Figure 6. The flyby status between the target satellite and the observing satellite significantly impacted the detection accuracy of the key satellite components. However, this aspect has also been disregarded in other published datasets.  
Figure 4: Examples of the satellite target in rolling states.