On Board Data Handling Research Articles

FloripaSat-2: An Open-Source Platform for CubeSats

This paper presents the FloripaSat-2 platform, an open-source service platform already on its second version, including, but not limited to, On-Board Data Handling (OBDH), Telemetry, Tracking and Command (TTC), and Electrical Power System (EPS) modules. The platform is conceived to be general-purpose, i.e., easily adaptable for missions with different payloads and requirements. In this context, an overview of the generic nanosatellite architecture, along with the ongoing missions in which it is being employed, is discussed, including the embedded systems, functionalities, and components. Also, the relevant source code is available in an online repository and can be used and expanded to different kinds of CubeSat missions. Finally, good practices regarding the development and a FlatSat proposal for faster testing of the subsystems are presented to aid engineers in testing and adapting the systems to their mission requirements.

Snapshot GNSS receivers for low-effort, high-gain space situational awareness

This paper proposes a novel concept of using highly efficient Snapshot Global Navigation Satellite Systems (GNSS) receivers to provide precise position fixes of single or multiple satellites in Low-Earth Orbit (LEO) to improve upper atmospheric modeling and thus contribute to superior space situational awareness (SSA). While tracking of LEO satellites and the use of onboard GNSS receivers for drag measurements and upper atmosphere modeling are well-established techniques, the expected advent of snapshot GNSS receivers for spaceborne scientific applications will allow massive improvements on the GNSS sensor’s Size, Weight, Power and Cost (SWaP-C). With chip-size dimensions of 4x4 mm2, a mass of less than 5 gr, an average power level below 0.1 mW, snapshot receiver technology is expected to provide position fixes in space with an accuracy of ∼19 m (3D r.m.s.), which will surpass the accuracy of Two-Line Elements (TLE) provided by the US Joint Space Operations Center (JSpOC) by at least two orders of magnitude. Equally important to their SWaP-C benefits, Snapshot GNSS receivers will allow mission and spacecraft designers to trade onboard-processing requirements versus payload downlink requirements, leading to either minimum onboard processing or a minimum amount of downlinked data. In this research, we establish the concept and architectural overview of using snapshot GNSS receivers for SSA, including the role of using them in a Distributed Space System (DSS), and detail their characterization and performance in terms of the required GNSS hardware and the impact of these payload on the power budget, the link budget and the OnBoard Data Handling (OBDH) budget of a satellite. It will be shown that these receivers lend themselves especially to their use on femto-, pico- and nano-satellites, although integrated snapshot modules may be flown as auxiliary payloads on micro- or mini-satellites as well. While this work focuses on the implications of the use of snapshot GNSS receivers on spacecraft design for the use of upper atmosphere modeling and SSA, their use may open up other science applications which avoid the need for expensive high-grade GNSS receivers.

The very high-speed SpaceFibre multi-lane CoDec: Implementation and experimental performance evaluation

On-board data handling sub-systems shall provide robust communication on-board spacecraft and have strict requirements in terms of reliability, fault-tolerance and redundancy. In the next years, on-board data handling sub-systems will be required to sustain high-speed payloads since satellites will host new high-resolution instruments, requiring a multi-gigabit data rate. The European Space Agency promotes the usage of a standard for the implementation of a very high-speed link for satellite on-board data-handling, SpaceFibre, that supports multi-lane communication links. Indeed, due to the stringent requirements of future on-board data handling subsystems, it will be necessary to have links that include more lanes to enhance system reliability and bandwidth. SpaceFibre aims at becoming the state-of-the-art for future on-board data handling subsystem, combining high-speed with high reliability and fault tolerance capability. In this paper, we introduce and report the development of an innovative multi-lane SpaceFibre core, and compares it with other promising space-oriented standards regarding multi-lane features. We present the results of a test campaign that aims at measuring SpaceFibre multi-lane performances in terms of recovery time after a lane failure, observing that the communication process can be completely restored between 4.42 μs and 6.30 μs. Implementation results on state-of-the-art space-oriented FPGAs, such as the Microsemi RTG4 and the Xilinx UltraScale Virtex KU060 are also included. Finally, we carry out a detailed power consumption analysis, including results for different core configurations, measuring the SpFi dynamic power consumption contribution to be between 576.7 mW and 148.4 mW for target configurations on a Microsemi RTG4.

Error Detection and Correction System (EDAC) of On Board Data Handling (OBDH) in Real Time Operating System Behaviour

The satellite requires the support of a robust sub system. On Board Data Handling (OBDH) is the core function of the satellite subsystem and has to be error free in managing the operation of the satellite. It should withstand the harsh environmental conditions in space that has a lot of hazards caused by radiations. In view of these two conditions, the OBDH design should be able to manage the operation and overcome the hazards of radiation. In order to manage the operation Real Time Operating System (RTOS) was applied. RTOS was able to manage the task efficiently and effectively. In the aerospace domain, RTOS has become popular because of its strength in managing the operating system. Error Detection and Correction System (EDAC) system was applied to make OBDH more robust. This paper discusses the implementation of the EDAC system in tandem with the RTOS behaviour to manage the operation and increase the robustness of the system. The findings show that OBDH can be programmed successfully using RTOS to handle critical and robust operations.

Pre-flight qualification test procedure for nanosatellites using sounding rockets

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 the ground station. The test procedure validates data frame definition, communication protocol specification, hardware integration specification, among other functionalities. Three FloripaSat subsystems have been tested: Electrical Power 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.

Thermal Validation Testing of an Automatic Identification System (AIS) Receiver for Low Earth Orbit (LEO) CubeSat

The advancements in electronics technology make nanosatellite missions more varied. One of its missions is to retrieve Automatic Identification System (AIS) data from vessels on the ground. The type of nanosatellite made in this study is a CubeSat with a size of 1.5U. The AIS receiver is created using RFIC Si4362 and MSP430G2553 Microcontrollers to control the device. The main mission of AIS Receivers is to receive and decode AIS signals at the frequency of 161.975 MHz and 162.025 MHz into the AIVDM NMEA0183 standard format. The decoded AIS data is sent to a Raspberry Pi Compute Module as On-Board Data Handling (OBDH) CubeSat before it is sent to the ground station. All of the CubeSat’s subsystems must be able to pass thermal testing before being launched into orbit. Thermal testing is performed to observe the performance of subsystems in extreme conditions similar to CubeSat conditions in space. Thermal testing is carried out at the Satellite Technology Center (Pusteksat) of the National Aeronautics and Space Agency (LAPAN) facility. The thermal test is done by running the device at temperatures of -20°C - 60°C for 3 hours and 56 minutes. The thermal testing indicates that the AIS Receiver can work in the orbital temperature range. After testing, the data reception success rate is 36.76% with a minimum RSSI value of -96dBm.

Designing on-Board Data Handling for EDF (Electric Ducted Fan) Rocket

The EDF (Electric Ducted Fan) rocket to launch requires a system of monitoring, tracking and controlling to allow the rocket to glide properly. One of the important components in the rocket is OBDH (On-Board Data Handling) which serves as a medium to perform commands and data processing. However, TTC (Telemetry, Tracking, and Command) are required to communicate between GCS (Ground Control Station) and OBDH on EDF rockets. So the design control system of EDF rockets and GCS for telemetry and telecommand needs to be made. In the design of integrated OBDH controller uses a lot of electronics modules, to know the behavior of rocket used IMU sensor (Inertial Measurement Unit) in which consist of 3-axis gyroscope sensor and Accelerometer 3-axis. To do tracking using GPS, compass sensor as a determinant of the direction of the rocket as well as a reference point on the z-axis of gyroscope sensor processing and used barometer sensors to measure the height of the rocket at the time of glide. The data can be known in real-time by sending data through radio modules at 2.4 GHz frequency using XBee-Pro S2B to GCS. By using windows filter, noises can be reduced, and it used to guarantee monitoring and controlling system can work properly.

A Software Architecture Design for Autonomous Formation Flying Control

Based on currently developed on-board platforms, this paper proposes a software architecture for orbiting spacecraft for autonomously establishing formation, station-keeping, and reconfiguring maneuvers. Components of the software architecture include orbital prediction (OP), orbital control (OC), and relative navigation (RN); these not only meet the constraining requirements of attitude control, thermal control, thrusters, and the ground-based operator, but also have a minimal impact on the on-board data handling (OBDH) system. All of the OP, OC, and RN algorithms are packaged as a subroutine (OPCNS) called by the OBDH system at regular intervals. The in-advance control instruction set (CIS) is temporarily stored in random access memory to be read by OPCNS as a formal argument, rather than in any fixed space of read only memory. The simplified general perturbations 4 method is introduced to perform a specific time interval of OP based on filtered relative measurements of RN. The relative-orbital-element (ROE) control method is employed to create in-advance instructions, depending on whether or not the predicted ROEs trigger the threshold values of any maneuver and then to allocate these instructions into the CIS following the proposed relationship rules between all of the ROEs and the ground control instruction. To tolerate the temporary divergence of the RN filter after any orbital maneuver, an ROE-based unscented Kalman filter is enhanced by using the control instruction in current execution to accelerate the co- nvergence. A 3-craft formation scenario for interferometric synthetic aperture radar measurements is used to validate all of the functions of the proposed software architecture.

A Novel Simulation Approach to Extended Dynamic Fault Trees Analysis for Highly-reliable Satellite OBDH Subsystem

On-board data handling (OBDH) subsystem is the critical subsystem of satellite which is supplied with hot/warm/cold spare backups, also uses triplicated bus and redundant memories for high reliability. For satellite OBDH subsystem, we present an extended dynamic fault tree model (eDFT). Because analytic approach is restricted to particular models and some probability distributions of fault rate, we use Monte Carlo simulation to analysis eDFT instead of it. However, it needs much long time to implement Monte Carlo simulation, so we provide the transformation approach to accelerate the Monte Carlo simulation. Each eDFT gate can be implemented by logic gate of mathematical circuit. The analysis result of the approach shows that acceleration value changes over the size of the eDFT-TTFT units, number of FPGA logic gates of random number generators, and number of FPGA logic gates of TTFT, so this approach can be more accurate and much faster than computer- based simulation.

The Extended Dynamic Fault Tree Model for Fault-tolerant OBDH Software of Microsatellite

This paper presents the extended dynamic fault tree (eDFT) model for fault-tolerant On-board Data Handling (OBDH) software used in microsatellite. For high reliability, in case of the primary processor failure, hot/warm spare automatically and uninterruptedly start torun the OBDH software without critical data missing. Memory with triple-modular redundancy and communication bus with spare are frequently employed in OBDH subsytem design. The important feature of OBDH software which is different from hardware lies in software reconfiguration/redundancy. In safe mode, some of OBDH software modules, even the whole software, can be reconfigured. Because of the limitation of traditional fault tree regardless of dynamic redundancy, the eDFT must model this case to evaluate the instantaneous reliability of OBDH software. Time-to-failure tree (TTFT) can be used to implement the conversion of eDFT model. The result shows this approach is much fast and prompt, and the acceleration value is in direct proportion to TTFT units.

Simulation of Fault-Tolerant Space Systems Based on COTS Devices With GPSS

In microsatellite missions devoted to remote sensing, the cost-reliability issue is an important constraint. This paper presents a low-cost methodology to simulate the reliability of a system for the development of fault-tolerant space systems. This methodology does not rely on special facilities or expensive equipment and is focused on the onboard data handling (OBDH) system for microsatellite's remote sensing payloads with commercial off-the-shelf components. The method presented uses the general-purpose simulation system language to simulate the system's reliability when fault-tolerance techniques (FTTs) are applied to field-programmable gate arrays. The objective of the proposed methodology is to validate the mathematical model corresponding to the system's reliability or to compute the reliability when there is no mathematical model. Therefore, system-level decisions can be made, in order to select the most suitable components and develop the systems for microsatellites. Specifically, the OBDH computers must have a high reliability as a mandatory requirement for microsatellites. Moreover, the simulation provides statistics to support decisions regarding the necessary FTT to be implemented.

Model-Driven Design of Real-Time Software for an Experimental Satellite

Model-driven engineering has gained widespread interest as a means to raise the abstraction level in software development, thus lowering cost and increasing efficiency. In this paper, a case study on using this approach to design the real-time software for UPMSat-2, an experimental micro-satellite, is described. The functionality of the software includes attitude determination and control, on-board data handling, platform monitoring and control, and payload management. A mix of modelling and software engineering tools have been used, enabling automatic code generation of most of the application software. The lessons learned from such an approach are analysed in the paper, and the use of model-driven engineering in real-time control systems is discussed.

Error Detection and Correction System (EDAC) of On Board Data Handling (OBDH) in Real Time Operating System Behaviour

The satellite requires the support of a robust sub system. On Board Data Handling (OBDH) is the core function of the satellite subsystem and has to be error free in managing the operation of the satellite. It should withstand the harsh environmental conditions in space that has a lot of hazards caused by radiations. In view of these two conditions, the OBDH design should be able to manage the operation and overcome the hazards of radiation. In order to manage the operation Real Time Operating System (RTOS) was applied. RTOS was able to manage the task efficiently and effectively. In the aerospace domain, RTOS has become popular because of its strength in managing the operating system. Error Detection and Correction System (EDAC) system was applied to make OBDH more robust. This paper discusses the implementation of the EDAC system in tandem with the RTOS behaviour to manage the operation and increase the robustness of the system. The findings show that OBDH can be programmed successfully using RTOS to handle critical and robust operations.

Preliminary Hardware Design and Development of On-Board Data Handling for Pico-Satellite in National Space Agency

Malaysia had in the past sent two remote sensing satellites to orbit by collaborating with foreign space companies to build homegrown capacities for space technology development. At the educational institutions, a pico-satellite development program would be an ideal first step to establish such capacity as students could gain the experience and know-how through the complete cycle of designing, building and testing a satellite. As it is now, some of their overseas counterparts have already succeeded in running CubeSat programs due to strong support from kit manufacturers and their national space agencies. However, the cost to purchase such kits could be discouraging and National Space Agency (ANGKASA) recognises the needs to initiate some designs that could be used or referred to for further development or expansion. In this paper, a hardware design of On-Board Data Handling (OBDH) board using PIC Microcontroller is presented. OBDH is a main subsystem which controls all subsystems in the satellite. It provides a series of important services like command, telemetry, data communication, data acquisition, process, storage and management. The PIC Microcontroller made by Microchip Corporation is chosen as it is widely used by the industry and academia in Malaysia. The 16-bit PIC24 microcontroller has been recognized as a suitable part due to its performance, memory, peripherals, cost effective solutions as well as availability. The method used in designing the OBDH in this pico-satellite is first based on a main mission to investigate ionospheric effect on GPS signal transmission. Other considerations taken are that the parts used should be of commercial off the shelf product and having its own development board for ease of testing. The expected result would be the successful arrangement of all required parts in limited pico-satellite’s size and the accomplishment in achieving the satellite’s missions through simulation.

Assessment of Earth Remote Sensing Microsatellite Power Subsystem Capability during Detumbling and Nominal Modes

The Electric Power Subsystem (EPS) is one of the most critical system on any satellite because nearly every other subsystem requires power. This makes the choice of power systems the most important task facing satellite designers. The main purpose of the Satellite EPS is to provide continuous, regulated and conditioned power to all the satellite subsystems. It has to do that withstanding the radiation, thermal cycling, and vacuum of a hostile space environment as well as the subsystem degradation over the time [1]. The EPS power characteristics are determined by both the parameters of the system itself and by the satellite orbit RI After the satellite separates from the launch vehicle (LV) to its orbit, in almost situations, all the satellite subsystems (attitude determination and control, communication, and onboard computer and data handling (OBCD estimation the solar arrays illumination parameters and determination of the efficiency of solar arrays during both detumbling and nominal modes.

A novel autonomous low-cost on-board data handling architecture for a pin-point planetary lander

There has been increased interest in the exploration of the Moon in recent years. Pin-point precision landing is highly desirable for future lunar missions. This paper is concerned with the design of the on-board data handling (OBDH) subsystem for the pin-point lunar lander of the Magnolia-1 project, funded by NASA. Four proposed on-board data handling architectures are outlined and compared in terms of power consumption, performance and reliability. Implementation results are presented, which are obtained from prototyping of the flight computer for the optimal OBDH architecture option on a Xilinx Virtex-5 Field Programmable Gate Array.

An extensible on-board data handling software platform for pico satellites

Miniaturization techniques enable the realization of very small satellites with interesting capabilities in space science. The University of Würzburg contributed in the scope of the cubesat program with its own pico satellite UWE-1, which is in orbit since October 2005. Despite reliable and stable operation of the on-board data handling (OBDH) system during the UWE-1 mission, the successor UWE-2 will be equipped with a more sophisticated, modular and extensible OBDH system, which was designed to facilitate the further development of the UWE satellite platform. The OBDH system was designed for high reliability and stability, but with an easier extension capability. The modular structure of the new system thus supports potential transfer to other satellite platforms.

DSP implementation of integrated store-and-forward APRS payload and OBDH subsystems for low-cost small satellite

The developed system, based on the DSP (Digital Signal Processor), provides an integrated store-and-forward APRS (Automatic Packet Reporting System) payload and OBDH (On Board Data Handling) subsystems at a very low cost and on a single board with dimensions less than 10 cm × 10 cm, thereby enabling a new level of performance for CubeSat-class spacecraft. In this paper, we consider the problem of designing a low-complexity AFSK and GMSK modems for a satellite communication link where the constraints on satellite power budget, antenna size, and data rate are such that the available transmit power, aboard the Picosatellite, is 1 Watt. To cut down the cost of the Picosatellite, we give a particular attention to software optimization due to use of small amount of 8K words Radiation Hardness ROM memory containing the application program. We have defined a methodology approach based on two design steps: algorithmic optimization, and optimal programming using Assembler language. Due to the radiation in space and the constraints of the Picosatellite, some measures regarding volume, mass, power, cost and radiation tolerance, had to be taken into consideration when the system was designed.

Study on the on-Board Computer System Based on ARM Processor

The new fault-tolerant onboard computer(OBC) with dual processing modules is presented to improve the micro-satellite data handling. Each processing module is composed of 32-bit ARM processor. Using the fault tolerance method, The OBC's hardware structure is implemented based on commercial-off-the-shelf (COTS) devices. As well as, a detail analysis of the fault handling mechanism and the software architecture is given. Considering the demanding of the extremely tight constraints on mass, volume, power consumption and space environmental conditions, the new fault tolerant onboard computer's data handling is enough to meet the micro-satellite missions.

Mature systems for small satellite missions

Over the past several years Satellites International has developed an integrated suite of satellite sub-systems and small satellite buses. The sub-systems include S-band communications, attitude sensing and control, power conversion and distribution, and on-board data handling. They are inherently modular and readily adaptable to different satellite configurations, a concept known as semi-standardisation. This concept has been adopted by two generic low-cost buses: MicroSIL for satellites in the mass range 40–80kg; and MiniSIL for satellites in the range 100–500kg. Their architecture is based on the semi-standard sub-systems, but easily modified to utilise sub-systems from other manufacturers. They can support all stabilisation methods including spinning, 3-axis control and gravity gradient and are adaptable to a wide variety of missions including Earth resources, scientific, communications and technology demonstration. The Company also manufactures a range of low cost ground support equipment and complete ground stations to complement the space-borne systems.