## 4 Design Analysis
### Power Analysis  
The design of the solar panel structure combines deployable solar panels since the power consumption of Light-1 is considered relatively high for a 3U CubeSat. Yet, the deployable solar panels do not provide sufficient power for the mission. Therefore, to solve the power insufficiency, a new mode of operation, the Sun horizon pointing mode, is implemented. In this mode, the CubeSat will be tilted off Nadir with an angle that varies depending on the Sun vector. This mode increases the power generation of the solar panels since the CubeSat changes its orientation to maximize the power generation. Figure 8 demonstrates the Sun horizon pointing mode. The blue line represents the payloads on the \(+Z\) and \(-Z\) axis, while the yellow cone represents the Light-1 main solar cells (deployable) on the \(+X\) face. In this mode, the payload is looking at the horizon continuously while performing yaw and roll attitude maneuvers to point the main solar panels (\(+X\)) toward the Sun. The power generation of Light-1 was simulated using the Systems Tool Kit (STK) by mimicking the attitude of Light-1 in the Sun horizon pointing. The objective of the power generation simulation in STK was to calculate the expected power generation when Light-1 is in its orbit, with its intended pointing mode and the capacity of its solar arrays. To simulate the power generation for the sun horizon pointing mode, which is a non-typical pointing mode, the attitude of Light-1 was mimicked. The attitude type selected in STK was 'aligned and constrained', which gives the freedom of aligning an axis of the satellite with a specific object and constraining a second axis with another object. In Light-1's sun horizon pointing mode, the \(-Z\) axis was constrained by the Sun and the \(  
aligned with the Nadir axis. In addition, the power generation of Light-1 was simulated for Nadir and full Sun tracking pointing modes. Since these two pointing modes are standard, these were present as direct options in STK. The results of the power generation simulated are illustrated in Table 3. The results show that the Sun horizon pointing mode generates more power compared to the Nadir pointing mode. Hence, the Sun horizon pointing mode is capable of providing sufficient power for the mission as illustrated in the power budget. The payload will operate most of the time during the tropical regions with a latitude of \(-23^{\circ}\) to \(+23^{\circ}\). By using simulations to find the duration according to the orbit duration, the results show it is approximately 50% of the orbit. All three ground stations will be utilized to communicate with Light-1 and attain the payload and housekeeping data. \(S-band\) transceiver is mainly used to download payload data. The UHF transceiver will download the housekeeping data and transmit beacons. Beacon transmission will require operating the transmitter around 6.2 min. The duty cycles of the \(S-band\) transceiver and the UHF transceiver are computed based on the maximum access times to the ground stations. Therefore, the maximum access time to Abu Dhabi ground station is 6.5 and 5.1 min for Vilnius and Aalborg ground stations, respectively. The access time of Vilnius and Alborg ground station is less of that compared to the ground station in Abu Dhabi since there is an overlap of the access time as they are close to each other. The power budget of Light-1 is calculated by considering the power generation and consumption during different modes of operation. Since the power generation was calculated from STK, the next step was to compute the amount of power consumed during the different modes of operation. In each mode of operation, different components will operate for a specific time in the orbit, i.e., certain components will be switched off, others will operate for a certain time during the orbit, while others will be operating throughout the orbit. Thus, the duty cycle of each component was retrieved, along with the power consumption.