Design Solutions For Modular Satellite Architectures

The cost-effective access to space envisaged by ESA would open a wide range of new opportunities and markets, but is still many years ahead. There is still a lack of devices, circuits, systems which make possible to develop satellites, ground stations and related services at costs compatible with the budget of academic institutions and small and medium enterprises (SMEs). As soon as the development time and cost of small satellites will fall below a certain threshold (e.g. 100,000 to 500,000 €), appropriate business models will likely develop to ensure a cost-effective and pervasive access to space, and related infrastructures and services. These considerations spurred the activity described in this paper, which is aimed at: - proving the feasibility of low-cost satellites using COTS (Commercial Off The Shelf) devices. This is a new trend in the space industry, which is not yet fully exploited due to the belief that COTS devices are not reliable enough for this kind of applications; - developing a flight model of a flexible and reliable nano-satellite with less than 25,000€; - training students in the field of avionics space systems: the design here described is developed by a team including undergraduate students working towards their graduation work. The educational aspects include the development of specific new university courses; - developing expertise in the field of low-cost avionic systems, both internally (university staff) and externally (graduated students will bring their expertise in their future work activity); - gather and cluster expertise and resources available inside the university around a common high-tech project; - creating a working group composed of both University and SMEs devoted to the application of commercially available technology to space environment. The first step in this direction was the development of a small low cost nano-satellite, started in the year 2004: the name of this project was PiCPoT (Piccolo Cubo del Politecnico di Torino, Small Cube of Politecnico di Torino). The project was carried out by some departments of the Politecnico, in particular Electronics and Aerospace. The main goal of the project was to evaluate the feasibility of using COTS components in a space project in order to greatly reduce costs; the design exploited internal subsystems modularity to allow reuse and further cost reduction for future missions. Starting from the PiCPoT experience, in 2006 we began a new project called ARaMiS (Speretta et al., 2007) which is the Italian acronym for Modular Architecture for Satellites. This work describes how the architecture of the ARaMiS satellite has been obtained from the lesson learned from our former experience. Moreover we describe satellite operations, giving some details of the major subsystems. This work is composed of two parts. The first one describes the design methodology, solutions and techniques that we used to develop the PiCPoT satellite; it gives an overview of its operations, with some details of the major subsystems. Details on the specifications can also be found in (Del Corso et al., 2007; Passerone et al, 2008). The second part, indeed exploits the experience achieved during the PiCPoT development and describes a proposal for a low-cost modular architecture for satellite

Miniaturized Radio Tranceiver for PocketQubes, Exceeding Performance of CubeSat Solutions

In this paper, a detailed design is presented of a communications module that is designed to fit tight PocketQube design budgets but still offer performance at least comparable to commercial off-the-shelf CubeSat solutions. The communications module features extremely efficient power usage, less than 2 Watt DC for 1 Watt RF output while fitting in an extremely small volume, (42 x 42 x 8mm, approximately a quarter of the volume of CubeSat solutions). Our system also features a new communication scheme based on Short Block LPDC codes that provides a very high code gain (approximately 6dB for hard-decision and 9dB for soft-decision) using a high code rate. A ground modem implementation based on GNURadio is also presented, taking advantage of a new implementation for low-latency asynchronous data transmission

A Pico-Satellite Design to Demonstrate Trajectory and Science Applications

This paper presents the design, integration and testing of a pico satellite, Delfi-PQ, a 3P PocketQube developed by Delft University of Technology, expected to be launched at the end of 2020. The main goal of this project is creating a miniaturized platform for future space missions with performances comparable to CubeSats, taking advantage of the miniaturization of electronic components and their integration. Education of aerospace engineering students is a second key goal of the project, where students involved in the project as part of their curricular activities

LUMIO: achieving autonomous operations for Lunar exploration with a CubeSat

The Lunar Meteoroid Impacts Observer (LUMIO) is one of the four projects selected within ESA’s SysNova competition to develop a small satellite for scientific and technology demonstration purposes to be deployed by a mother ship around the Moon. The mission utilizes a 12U form-factor CubeSat which carries the LUMIO-Cam, an optical instrument capable of detecting light flashes in the visible spectrum to continuously monitor and process the meteoroids impacts. In this paper, we will describe the mission concept and focus on the performance of a novel navigation concept using Moon images taken as byproduct of the LUMIO-Cam operations. This new approach will considerably limit the operations burden on ground, aiming at autonomous orbit-attitude navigation and control. Furthermore, an efficient and autonomous strategy for collection, processing, categorization, and storage of payload data is also described to cope with the limited contact time and downlink bandwidth. Since all communications have to go via a Lunar Orbiter (mothership), all commands and telemetry/data will have to be forwarded to/from the mother ship. This will prevent quasi-real time operations and will be the first time for CubeSats as they have never flown so far from Earth

Collaborative open hardware development: lesson learned from PQ9

This presentation highlights the efforts done at the Space Systems Engineering group at the Deft University of Technology related to open and collaborative hardwar development. It presents the PQ9 standard that was developed for femto satellites and PocketQubes. It was presented at the Open Source CubeSat Workshop (Nov 22nd and 23rd 2017) in Darmstadt (https://oscw.space)

Building radio systems from digital parts: a HF radio transmitter on a FPGA developement board,

The paper describes a sequence of laboratory exercises focused on designing and building a TX-RX radio chain where all the processing uses digital circuits (SDR approach). The students have access to a high-level codesign environment, which allows to design, simulate and synthesize analog/digital systems. They can explore a variety of design solutions, and use tools very close to industrial practices. The transmitter core is a Direct Digital Synthesizer (DDS), with AM and FM modulation capability. The transmitter uses on-board ADC and DAC, with direct RF output. TX parameters are selectable from the on-board switches. Tx testing is carried out using commercial radio receivers, but also some units of the receiver chain are designed, built, and tested. 1

Design Solutions for a University Nano-Satellite

Abstract—Many universities are now involved in projects related to design, assembly, and operation of small satellites. These projects, with participation of researchers and students, and support of external companies, do not aim to compete with commercial satellites; the main goal is to increase the experience level which contributes to make space applications affordable also to small organizations. For students, participation in the complete process of satellite design, assembly, and testing, offers a unique experience within an interdisciplinary complex project. External companies are involved in creating a community of researchers focused on space applications, thus creating new markets and opportunities. The paper describes the architecture and design solutions of a small satellite developed at Politecnico di Torino in the above mentioned context. The main design goal was to combine the usually conflicting cost and reliability constraints; cost has been limited by using properly selected COTS (Commercial Off The Shelf) devices. Reliability has been achieved through redundancy and design diversity. Focus of the paper is on overall satellite design and architecture, with details of solutions to enhance reliability down to the hardware level. The experience led to the development of a new course (Master level) and to several new projects currently unde