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KESSLER SLONGO ET AL. power point tracking (MPPT) techniques, high-efficiency solar cells, and energy-aware scheduling algorithms are some of the hot topics under research nowadays. Due to size restrictions and aiming low complexity in design, many nanosatellite designers adopt the direct energy transfer (DET) architecture. KySat-2 is an example of a successfully accomplished mission, based on this EPS topology. Designed by Morehead State University Space Science and Engineering group, KySat-2 EPS was powered by a set of gold-plated deployable solar panels with 26% of efficiency. It provided four high-power regulated rails (two 3.3 V and two 5 V) and a low-noise, low power 3.3V rail for noise-sensitive devices. The energy storage system was made of three 18650 lithium-ion cells connected in series, and the high-power rails reached efficiencies approaching 90%. 12,21 Aiming minimum space occupation and low power consumption, the EPS proposed for the AraMiS project has a boost regulator operating the solar panels close to their MPP. 16 In order to reduce the number of components, the designers opted by the constant voltage MPPT algorithm, using only analog devices. The EPS steps up solar panels voltage from 4.4 V to the distribution bus voltage level (14 ± 2 V). It provides power buses with 3.3 and 5 V voltage levels. The EPS efficiency analysis is demonstrated, calculating the main components power losses. Although this is a very detailed and well-described work, it does not compare the proposed solution with other EPS architectures. A 3U EPS efficiency analysis is presented by Gonzalez-Llorente et al. 22 The subsystem is based on a buck converter that steps down the solar panels voltage (15 or 7.5 V) to the litChium-ion battery range of 3.3 or 6.6 V. The authors define an optimum operation point for the DC-DC converter in order to achieve its maximum efficiency. The operation point is defined by the converter input voltage, output voltage, and output power. Therefore, the discussion is based on different solar cells connections configurations, and battery cells arrangement, that result in the most efficient EPS configuration. Different scenarios have been analyzed to achieve 98% of peak efficiency on the best configuration: input voltage of 7.4 V, output voltage of 3.3 V, and output current varying from 0.1 mA to 2.1 A. Only the buck converter topology is discussed in this paper, and it does not consider any MPPT technique. An interesting solution adopted for the ERPSAT-1 picosatellite uses fuzzy logic to obtain energy harvesting maximization. 23 The developed subsystem has three main blocks, which are the fuzzy maximum power point tracker, the power conditioner, and the hierarchical fuzzy subsystem controller. The fuzzy logic algorithm has been implemented in a dedicated microcontroller that controls a boost converter. Simulations have been performed to demonstrate the better efficiency of the proposed method when compared to the Perturb and Observe MPPT algorithm. Although a comparison is provided in this work,...

et al.. Pre-flight qualification test procedure for nanosatellites using sounding rockets. Acta Astronautica, Elsevier, 2019, 159, pp.Abstract This work presents an innovative procedure to test nanosatellites subsystems on board sounding rockets. The procedure allows the subsystems to save their telemetry data during the whole rocket flight phases (including at the rocket lift-off). The subsystems of the FloripaSat (1U CubeSat) engineering model have been tested on board a VSB-30 rocket in order to validate their design and integration process. A dedicated embedded system has been proposed to operate as an electronic interface between the nanosatellite subsystems and the rocket electronics. Also, a system to process telemetry data was implemented on * Corresponding author Email addresses: slongo@eel.ufsc.br (Leonardo Kessler Slongo), jgreis@lisha.ufsc.br (João Gabriel Reis), daniel.gaiki@studenti.polito.it (Daniel Gaiki), pedro@labtucal.ufsc.br (Pedro Von Hohendorff Seger), sara.vega@posgrad.ufsc.br (Sara Vega Martínez), bruno.eiterer@grad.ufsc.br (Bruno Vale Barbosa Eiterer), tulio.gomes.pereira@grad.ufsc.br (Tulio Gomes Pereira), mario.baldini@posgrad.ufsc.br (Mario Baldini Neto), m.frata@grad.ufsc.br (Matheus dos Santos Frata), henrique.hamisch@grad.ufsc.br (Henrique Daniel Hamisch),Subsystem (EPS); Telemetry, Tracking and Command (TT&C); and On Board Data Handling (OBDH). Several nanosatellites' functions have been evaluated, including: battery monitoring; inertial measurement unit; temperature measurements; radio transceiver; and beacon. The flight results were considerably different from the results obtained at the laboratory. This has allowed important modifications to be made on the design of the CubeSat flight model as the revision on the radio circuit on TT&C and the implementation of an external battery charger circuit for the EPS.Keywords: Test procedure, design validation, nanosatellite, sounding rocket 65 ditions. Even real nanosatellite missions can not provide data to this analysis, since the spacecrafts are placed in the P-POD (or equivalent launching device) during the flight, obligatorily in switch off condition. Laboratory qualification tests are essential, and they may be performed with the satellite subsystems collecting data. However, the physical phenomena are treated separately in 70 each test (vibration, acceleration, mechanical shock, temperature cycling, etc.), and normally, in a lower level of intensity (specially for nanosatellite projects).These are the reasons why this test procedure has been proposed, believing that new data may arise from these suborbital flights, which will help nanosatellite designers in their projects. 75 Besides the procedures of nanosatellite's subsystem configuration and integration, this paper also describes the design of the Multi-Mission Platform (MMP), which is an embedded system conceived to allow nanosatellite tests (and other experiments) aboard sounding rockets. This platform is based on a 4 180 experiment's goal is to test a thermal device, as wel...