Physical modelling and research of navigation, orientation and communication subsystems characteristics of the CubeSat format educational nanosatellite
Object of research is the educational nanosatellite (further NS) a format 2U CubeSat.
Objects of research are a subsystem of navigation for NS on an earth orbit with receiver GPS/GLONASS, a subsystem of orientation of NS, a subsystem of communication of NS to ground station with a format of data interchange AX.25 and BPSK modulation.
The operation purpose is development of subsystems of navigation, orientation and communication of NS by methods of physical modeling and an experimental research of the main parameters of subsystems.
The primary goals which were decided for achievement of the above-stated purpose, consisted in development of high-precision subsystems of navigation (determination: speeds - 0,05 m\s, altitudes-5m), orientations and communications which can be used as unitized subsystems for different constructions of small-size space ships. Including, their are support of collection of telemetry onboard NS, its conversion, saving of results to own memory with a subsequent information transfer to the other subsystem, both in real time, and with a time delay.
Namely, following in essence new valuable scientific results and new technological decisions are received:
- Physical model of an electronic platform of NS with subsystems of navigation, orientation, communication;
- A mathematical model of integration of flight trajectory of NS with usage of measurements GLONASS/GPS of the receiver, refinement of flight trajectory of the satellite,
- Mathematical model of forecasting of communication sessions onboard NS;
- High-precision subsystems of navigation (determination are developed: speeds - 0,05 m\s, altitudes-5), orientations and communications which can be used as unitized subsystems for different constructions of small-size space ships. It will allow to improve the main technical performances of subsystems of navigation, orientation and communication of NS by the usage of high-precision receiver GPS/GLONASS of signals produced in Ukraine.
- NS date transmission through serial interfaces RS-485, RS-422, RS-232 without usage of specialized protocols of a data interchange does not give the chance to estimate an amount of the lost packets and their integrity. For this reason necessary protocols for operation with GPS/GLONASS receiver CH-4706, and the communication protocol for a data interchange with other subsystems which will be installed on board which give the chance to exchange actual data in time and minimum loss have been implemented.
- The new model of a thermal status of main systems and generally NS which considers a satellite position in an orbit, thermal loads which act on it, and heat generation by separate elements of systems is developed.
- New experimental data of terrestrial researches of system of support of thermal modes of the nanosatellite engineering model, its elements and model of the satellite in the conditions of action of space factors are received;
- Technological recommendations about modeling of subsystems of communication, navigation and orientation for the nanosatellite POLYITAN-2-SAU are developed
- New thermal characteristics experimental data of the main subsystems of the satellite are received. The program and a nanosatellite testing technique in the conditions of influence of the main negative factors of a space taking into account its orientation in an orbit is developed.
- The software is developed for systems of navigation, orientation and NS communication.
- The software is developed for nanosatellite general control.
- On student's nanosatellite flight model the sketch design documentation is developed for the international project QB50 with following characteristics.
- Overall dimensions of flight model 100х100х225 the mm, weight about 2,1 kg, the maximum power consumption - is no more 2,4 W. Power supplies are supplied by means of three accumulators and 4 solar batteries. In a nanosatellite radio communication subsystem the radio transceiver with frequency of 437,95 MHz (downwards) and 145,5 MHz (upwards) with modulation BPSK is used, and also with two antennas the subsystem of navigation GLONASS/GPS is developed for reception of navigation signals.
The indicated new science and technical results allow to create in essence new constructions and subsystems of small space ships, including nanosatellites, and to use them for needs of an economy of Ukraine.