CubeSat Project Research Articles

CubeSat bus interface with Complex Programmable Logic Device

A standardized interface for different CubeSat missions is one of the keys to reducing costs and delivery time. A backplane interface approach, proposed by the University of Würzburg in Germany as UWE-3, was implemented in three CubeSat projects at the Kyushu Institute of Technology (Kyutech) to shorten the development and assembly times. The backplane approach also helped to reduce the risk of workmanship errors associated with the harness. However, changes to the proposed standard interface board were necessary in every CubeSat project, to comply with the mission requirements. To obtain more flexibility, especially for data connections, this work introduces a novel idea of a software-configurable bus interface with a backplane board. A Complex Programmable Logic Device (CPLD) was used instead of hardware routing so that we can reconfigure the bus interface by reprogramming the CPLD. The concept was validated by a functional test with a breadboard module. A radiation test verified that the selected CPLD has enough strength to survive total ionization doses of more than 2 years in low Earth orbit. A new backplane board with CPLD has been integrated into the engineering model of the fourth CubeSat project at Kyutech, the BIRDS-3 project, and system level verification has been conducted.

Analysis and design of a stacked power subsystem on a picosatellite

In 1999, the satellite classification was developed and given to a standard-sized, limited-weight picosatellite [1] in a multidisciplinary didactic format, signed between Stanford University and Polytechnic University of California. The CubeSat standard provides a development platform accessible to both universities and small businesses to develop research and technology at a reduced cost [2]. Furthermore, a CubeSat project uses commercial-off-the-shelf components to further reduce cost.

An In-The-Loop Simulator for the Verification of Small Space Platforms

The paper presents an end-to-end simulator aimed at supporting the engineering team in the design and verification activity across the whole product life cycle. The simulator is devoted to the analysis of small space systems, which present specific features if compared to large traditional platforms. Improving the understanding of the system early in the life cycle, and enhancing the verification process may help to increase the reliability and mission success of small-scale satellites while maintaining their key features of low cost and fast delivery. The simulator is designed through a Model and Simulation Based approach and allows performing in-the-loop simulations for the verification of functional and operational requirements at component, subsystem, and system level. The simulator is characterized by a modular architecture to adapt to several missions and different system configurations, also outside the space field. The core of the tool is a multi-processor workstation that sets up and runs the simulation, making use of a models database for the equipment and the mission environment, and a built-in interface unit to connect all the elements. The simulator has been successfully tested on a CubeSat project. Many test sessions were run and they are described into the detail in this article.

Temperature gradient sensor from pulsed power supply duty cycle in ultra‐low‐power energy harvesting system

Directly interfacing sensors that link sensors to micro-controllers without a signal conditioning circuit or an analogue-to-digital converter on the one side and energy harvesting systems on the other side are two key enabling technologies to create self-powered autonomous low-cost and low-maintenance sensor networks. In this reported work, both technologies are concurrently combined in such a way that the duty cycle of the pulsed power supply provided by the harvesting system itself yields in turn a temperature gradient sensor functionality. Originally conceived to power a low-power satellite beacon in a CubeSat project, it has found application, among other applications, in automatic air conditioning and heating systems aiming smart buildings.

B2 東京大学超小型衛星 CubeSat プロジェクトの成果について

CubeSat project has started primarily for an education purpose to improve student's skill of space engineering and project management. The CubeSat program at University of Tokyo, ISSL (Intelligent Space Systems Laboratory), has been started since 1999 and it's first nano satellite named "CubeSat-XI", developed by students, was successfully launched by a Russian rocket "ROCKOT" on June 30,2003. Since then, the satellite becomes operational and the students have been performing various experiments and demonstrations of its bus technologies and the onboard camera. This paper briefly reviews the systems description, the operation and the results achieved until present moment.

3322 東京大学 CubeSat-I の現状 : 開発を終えて

This paper describes the current status of the University of Tokyo's super-small satellite called "CubeSat". CubeSat project is the international joint program, which aims for developing and actually launching 10cm cubic satellites weighing less than 1kg to Low-Earth Orbit. University of Tokyo's CubeSat is a technology demonstration satellite to validate the pico-satellite bus system and the commercial-off-the shelf components in space as well as the Earth imaging mission. This paper shows the final design and current status of the satellite.