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D-Orbit SpA  I  Viale Risorgimento, 57 22073 Fino Mornasco, Como, Italy  I  +39 02 3792 0900  I  info@dorbit.space

VAT IT 07373150965  I  Terms of Use  I  Privacy Policy  I  Cookie Policy

Our goal is to ensure your success with products supporting the initial and the final phases of a space mission. For this reason, we invest in research and development projects to investigate new concepts, validate and qualify our hardware in space, and push the envelope of what is possible.

2017: D-SAT MISSION

D-Sat was a three-unit CubeSat designed, built, and operated by D-Orbit. It was launched into a 500 km sun-synchronous orbit on June 23rd, 2017 from the Satish Dhawan Space Centre in India, atop a PSLV rocket. During the first window of visibility, a few hours after launch, the team was already able to acquire the signal and receive the first telemetry. The main objectives of the mission were testing the functionality of  D3 in outer space and attempt a direct re-entry maneuver at the end of the mission.

During its 3 months-long mission, D-Sat successfully completed an eleven-week flight plan, during which it performed multiple iterations of SatAlert and DeCas experiments.

SatAlert, designed in collaboration between D-Orbit and the National Inter-University Consortium for Telecommunications (CNIT), University of Florence Research Unit, is an in-orbit validation of the Multiple Alert Message Encapsulation (MAMES) protocol, defined by ETSI (European Telecommunications Standards Institute). The experiment proved the viability of the encapsulation process, the transmission of MAMES over the space segment, and the reception and decoding by a portable Software Defined Radio User Terminal (SDR-UT). All the system components performed as expected, validating the whole alert messaging chain from the alert generation to the MAMES reception, including D-Sat’s onboard processing and broadcasting capability, the SDR-UT reception, and the web-based machine-to-machine communication mechanisms for data exchange. To validate the main features of MAMES, ground station operators generated and uploaded different types of MAMES messages. The success of the SatAlert Experiment is the first step towards a wider implementation and adoption of the MAMES protocol.

DeCAS (Debris Collision Alerting System), developed by Aviosonic Space Tech, is a patented system able to determine the dynamics of the debris footprint area associated with the re-entry of the hosting satellite. Upon re-entry of the hosting spacecraft, DeCAS survives the break-up phase and broadcasts the debris footprint dynamics forecast to civil protection agencies. In a real-world scenario, this information would be processed on ground and then transmitted in real-time to airplanes flying over that zone through the Air Traffic Control Center, and to the populated areas below through national public safety agencies.​

To validate the system, D-Sat’s ground operators have submitted 83 messages simulating uncontrolled re-entry. DeCAS was able to process in real-time more than 98% of these messages, which were afterward sent to CNIT for the encapsulation into MAMES protocol messages and for the consecutive upload. Ten of these alerts have successfully completed the entire process, simulating a DeCAS satellite broadcast service. Thanks to a collaboration with Ponti Institute and ARI of Gallarate, where Aviosonic had installed its ground station, all DeCAS messages have been received, along with more than 14 hours of D-Sat broadcasts, validating the whole system architecture. 

The firing procedure was performed at 22:18, local time, on October 2nd, 2017. After successful completion of all the steps of the decommissioning procedure, we activated Lampo and the motor fired as planned. Then we waited for the next orbital pass, expecting not to be able to acquire the signal. When we did acquire the signal, we realized that something didn't go as planned and that the satellite was still in orbit.

 

Diagnostic data we collected in the following days confirmed that D-Sat had in fact changed orbit, moving into an elliptical orbit with a different inclination. All the objectives related to motor ignition were reached, and the change in orbital parameters confirms that the motor produced the expected thrust, but with a different alignment from that needed for a decommissioning maneuver. The new orbit still complied with orbital debris regulations and was part of the scenarios we evaluated during mission planning.

 

A direct and controlled re-entry of D-Sat was a particularly difficult goal to achieve for a technical reason. From the structural point of view, D-Sat is a 4.5 kg three-unit, state-of-the-art CubeSat. The onboard motor was a version of Lampo designed for a satellite of at least 50 kg. The combination of these two elements presented some unknowns, especially regarding the ability of D-Sat to be able to maintain a correct pointing during the maneuver, which would have required an alignment of the thrust vector with the barycenter with a 1 mm tolerance. As in any space mission, we had to make a tradeoff that included a calculated risk.

We are working in an innovative sector where partial failures lead to progress; as a matter of fact, this mission proved that our technology was flight-proven, and allowed us to acquire a considerable heritage. 

D-SAT RECORDS

D-Sat has set many records in the space industry, with its completely redundant architecture, a pyrotechnic device compliant with the MIL-STD-1576 standard, and a solid rocket motor with a total impulse of 800 Ns. Our operators have been able to maintain contact with the satellite during the spin-stabilizing, pre-firing phase, even though the satellite was rotating on its axis at 780 rounds per minute, a result that many in the scientific and technic community doubted we could achieve. Finally, the satellite survived an orbital maneuver with a velocity of 70 m/s, a very high trust for such a small satellite, clearing the doubts many satellite manufacturers had about the possible impact of our product on their spacecraft. 

2013: ALICE 2

Alice 2 mission was planned to qualify the Brain and the Safe and Arm Device, two of our critical modules, against the ECSS standards.

The prototype included: Command and control subsystem; Software to operate the electronics system; Mechanical interface with device subsystem; Simplified interface with satellite subsystem; Two safe and arm devices.

The electronic system performed two functions, corresponding to those performed respectively by the Brain and the Safe and Arm Device. The first function was the ability to transmit from a receiving station sets of data related to the state of the deorbiting device and – optionally – of the satellite host. The second function was to activate a simulated ignition of the deorbiting device following the reception of a command from a transmitting station. 

Alice 2 demonstrated performance requirements, confirming the ability of the D-Orbit Decommissioning Device to work in a critical space environment. The qualification model successfully passed through qualification tests, described below, and Alice 2 Flight Model was accepted for launch from DNEPR launcher. On November 21st, 2013 Alice2 was sent in space.

All qualification tests were performed according to ECSS (RD-1) standards, which are ESA standard practice for the management, engineering and product assurance of aerospace projects and applications.

ECSS (RD-1) standards address the requirements by performing verification and testing of space segment elements and equipment on ground prior to launch.

Electromagnetic Compatibility Test