# TrackInk: An IoT-Enabled Real-Time Object Tracking System in Space  
[PERSON]  
1 Faculty of Science and Engineering, School of Engineering, Macquarie University, Sydney, NSW 2109, Australia; [EMAIL_ADDRESS] (C.A. );  
[EMAIL_ADDRESS] (K.A. );  
[EMAIL_ADDRESS] (S.M.) [PERSON]  
2 Faculty of Science, School of Computer Science, Queensland University of Technology, Brisbane, QLD 4000, Australia  
On the one hand, with rapid improvements in portable sensors, wireless sensor networks, and intelligent mobile devices, there has been a huge growth in the number of devices per user in recent years [29; 30; 31; 32; 33; 34; 35; 36]. On the other hand, there is particular interest in using these low-cost devices to perform complex calculations, raising policy enforcement and security issues in the IoT space [37; 38; 39; 40; 41; 42; 43; 44]. Particularly for those required for orbital mechanics analysis. Traditional satellite locating devices are complex, expensive, heavy-weight, non-transportable, and generally not feasible for amateurs, leaving them mostly for high-value applications [45; 46; 47; 48], indicating a demand for lightweight, cost-effective, and efficient tracking systems that can leverage the edge computing of IoT systems. Existing methods for tracking satellites in orbit, among other flying objects, include passive radar signal analysis for drone and air-target detection [49; 50], infrared thermal image processing for tracking hot flying objects [51], as well as visible light computer vision [52]. Another notable technology which detects aerial objects is Israel's Iron Dome [53], which utilises active radar technology to detect ballistic missiles mid-air before launching missiles that destroy the target missile mid-air. However, our approach is to provide a simple yet complete solution that can deliver accuracy with similar systems, e.g., above. A gap in the field of satellite tracking exists where greater portability is required. A project that requires a network of numerous small-scale interconnected devices, e.g., for complex optical satellite diagnoses or for three-dimensional (3D) imaging of satellites, a portable, low cost solution is desirable. To address these challenges, in this paper, we propose a framework called 'TrackInk'--a portable, cost-effective, and efficient tracking system that uses publicly available satellite data to track satellites in space (i.e., in orbit). TrackInk aims to solve the problem of portability and cost by using lightweight consumer-grade electronics, which can easily be powered with batteries and carried by anyone. Portability will also be ensured in the system by using sensors to determine where the device is located on Earth, along with its orientation, which will be compensated for in the program workflow [54; 55]. Various information from the system, e.g., geographical location and relative satellite position, will be published to an IoT analytics platform to provide remote system diagnostics. TrackInk helps in localising and tracking the elevation and azimuth of any given satellite with public Two-line Element (TLE) data. The system framework works by propagating satellite positions from TLE sets, thus, it is easy to modify the system to track additional or new objects with available TLE data. Publicly-available TLE sets are primarily used for satellites or orbital debris. Information about other celestial bodies is also available in different forms, which can also be converted into relative positional data for use within this system. Our proposed framework has the potential to track objects including celestial bodies along with artificial satellites and orbital debris that have publicly available data,  
Figure 1: Number of launches per year for currently active satellites [28]. X-axis corresponds to the year of launch for a given satellite and Y-axis corresponds to the number of currently active satellites (units). e.g., from CelesTrak [28]. This system provides the framework for additional projects relating to satellites and orbital debris.