The use of commercial off-the-shelf (COTS) components in CubeSat design offers flexibility, scalability, reduced project costs, and reduced development time. For these reasons, many space missions have adopted COTS platforms, owing to their advantages and limitations. An electrical power system (EPS) is a critical subsystem of COTS platforms that must meet mission requirements for the satellite to operate and guarantee mission success, including support for the operation modes and meeting the required lifetime. However, EPS validation is necessary to identify EPS characteristics such as energy generation, storage, power consumption, and management modes. The power budget is a crucial aspect in the validation, design, and correct selection of an EPS, which can reduce costs and ensure compliance with EPS requirements. In this paper, a method is proposed to validate the EPS characteristics of COTS platforms by analyzing the power budget according to mission specifications. The approach determines the power and energy for the operational modes and scenarios and evaluates the battery depth of discharge (DoD) and charge/discharge cycles. The effectiveness of the proposed method is demonstrated through a case study of the LEOPAR mission, a 3U CubeSat satellite. The results show that the EPS can meet the power demands of the satellite subsystems during the mission. Our method provides a systematic and easy-to-follow process for validating CubeSat satellite EPS and can significantly enhance the development process for these satellites. It also contributes to the small-satellite community by providing a valuable tool to ensure the success of CubeSat missions.
Several recent studies have attempted to formulate printable cementitious materials to meet the printing requirements, but these materials are designed to work with specific printing equipment and printing configurations. This paper aims to systematically develop and perform characterization of a commercially available ultra-high-performance concrete-class material (UHPC) modified to be printable. Four percentages of superplasticizer were used (100%, 94%, 88%, 82%) to adjust the UHPC mixture for 3D-printing requirements. A superplasticizer amount of 88% was considered adequate to meet the requirements. Several fresh and hardened properties of UHPC were measured experimentally: shape-retention ability and green strength were investigated in fresh state, and compressive and flexural strength were evaluated in three loading directions to evaluate the anisotropic effects. Furthermore, the strength of the interlayer bond was investigated. The UHPC developed in this study met the criteria for extrudability, buildability, and shape retention to ensure printability. In comparison with mold-cast UHPC, printed UHPC exhibited superior flexural performance (15–18%), but reduced compressive strength (32–56%). Finally, the results demonstrated that a commercially available UHPC-class material can be used for 3DCP, which possesses all necessary properties, both fresh and hardened.
Context: Unmanned Aerial Vehicles (UAVs) equipped with remote sensing platforms have become increasingly popular due to their applications in aerial surveillance, environmental control, and disaster response. However, the limited flight range and on-board energy resources of UAVs pose significant challenges to their practical deployment and operating efficiency, which has led to the exploration of energy-efficient platforms for remote sensing. Method: This paper proposes a preliminary approach for UAV multi-sensor reconnaissance and surveillance platforms (MRSS) that target low energy consumption. The approach implemented four sensor modules controlled by one multi-functional integrated edge computer for control and data collection, which can be interchanged according to battery lifetime requirements. Results: The main contribution of this work was an analysis of the energy consumption behavior of sensor modules managed by an embedded system with edge computing capabilities as the central control unit. Conclusions: The high energy consumption associated with modules such as GEOINT leads to deep discharge in excess of 20 % DOD, resulting in a maximum battery degradation of 2,4 years.