Search Results (3)

The commercial space launch sector is currently undergoing a significant shift, with increasing competition and demand for launch services, as well as growing concerns about the environmental impact of rocket launches. To address these challenges, within the New Space Portugal project scope, a multidisciplinary framework for designing and optimizing new launch vehicles is proposed. Creating a more resilient and responsible space industry can be achieved by combining technological innovation and environmental sustainability, as emphasized by the framework. The main scope of the framework was to couple all the disciplines relevant to the space vehicle design in a modular way. Significant emphasis was placed on the infusion of ecodesign principles, including Life Cycle Assessment (LCA) considerations. Optimization techniques were employed to enhance the design and help designers conduct trade-off studies. In general, this multidisciplinary framework aims to provide a comprehensive approach to designing next-generation launch vehicles that meet the demands of a rapidly changing market while also minimizing their environmental impact. A methodology that leverages the strengths of both genetic and gradient-based algorithms is employed for optimizations with the objectives of maximizing the apogee altitude and minimizing the Global Warming Potential (GWP). Despite only being tested at the moment for sounding rockets, the framework has demonstrated promising results. It has illuminated the potential of this approach, leading to the identification of three optimal designs: one for maximizing the apogee, another for minimizing GWP, and a compromise design that strikes a balance between the two objectives. The outcomes yielded a maximum apogee of $6.41$ km, a minimum GWP of $9.06$ kg ${\mathrm{CO}}_{2_{eq}}$, and a balanced compromise design featuring an apogee of $5.75$ km and a GWP of $25.64$ kg ${\mathrm{CO}}_{2_{eq}}$. Full article

Recent developments in electromagnetic launchers have created potential applications in transportation, space, and defense systems. However, the total efficiency of these launchers has yet to be fully realized and optimized. Therefore, this paper introduces a new design idea based on increasing the magnetic flux lines that facilitate high output velocity without adding any excess energy. This design facilitates obtaining a mathematical equation for the launcher inductance which is difficult to analytically represent. This modification raises the launcher efficiency to 36% higher than that of the ordinary launcher at low operating voltage. The proposed design has proven its superiority to traditional launchers, which are limited in their ability to accelerate microsatellites from the ground to low Earth orbit due to altitude and velocity constraints. Therefore, an aircraft is used as a flying launchpad to carry the launcher and bring it to the required height to launch. Meanwhile, it is demonstrated experimentally that magnetic dipoles in the projectile material allow the launcher coil’s magnetic field to accelerate the projectile. This system consists of the launcher coil that must be triggered with a high amplitude current from the high DC voltage capacitor bank. In addition, a microcontroller unit controls all processes, including the capacitor bank charging, triggering, and velocity measurement. Full article

Satellite systems undergo several operational phases during their service life, including the assembly phase, ground transportation phase, the launch phase, and the in-orbit operation phase. Among these phases, the one that imposes the highest level of loadings on the satellite is the launch phase. This phase involves a number of highly dynamic loads, all being imposed upon the satellite simultaneously. Investigation of the responses of the structural subsystem of a satellite to these loadings, namely its maximum deformations and maximum von Mises stresses, is critical if a reasonably high level of confidence is to be achieved. This confidence is in terms of ensuring that no material yielding develops in the structure as a result of the imposed launch loadings. In an earlier work, the structural subsystem of a conceptual microsatellite was designed, employing aluminum 6061 alloy as its material. It was then modified through introducing sets of parametrically defined geometric patterns as perforation patterns to remove material, towards reducing the structure’s total mass, as an alternative to employing composite materials. That effort led to a mass reduction percentage of 23.15%. The current work’s research effort focused on computing the responses of the perforated structure to three of the dynamic launch loads that are imposed upon satellites while being launched, namely quasi-static, random, and shock loads. These responses were then compared to those of the baseline, unperforated, version of the same structure. The values of these loads were taken from the relevant sources, with the values being nominal, and represented the loads that any satellite must qualify for before it can be accepted by the provider for inclusion in a launcher. After imposing these load values upon the structural design it was found that the structural responses indicated that the structure would successfully survive these loads without developing stresses that would lead to material yielding failure. This was deduced from computing the yield margins of safety for each loading case, and all margin values were positive, indicating that the structure, at its current development stage, did have sufficient capacity to withstand these loads without material yielding. This reinforced the conclusion of the earlier work, namely that the perforation concept did have sufficient merit to be further developed towards being implemented in future satellite designs. Full article