The Spacecraft Bus

The spacecraft bus serves as the primary system that supports all other spacecraft hardware. Designed to accomodate various mission specific payloads with high reliability, this structure supports all other spacecraft hardware.

MagicBus platform currently enjoys flight heritage on several small satellite missions and has demonstrated multi-mission adaptability. Its modular design features lower part count and greater accessibility, making it the ideal solution for microsatellites.

The onboard bus

Spacecraft buses serve as the foundation for space vehicles’ engineering subsystems, including power, communications, propulsion and attitude control systems. Furthermore, sensors track their orbits.

Spacecraft bus technology enables standardization and modularity in satellite design, thus reducing costs and improving reliability while making mission creation faster and simpler. Spacecrafts consist of two major parts – payload (mission-specific equipment that carries out Earth Observation or remote sensing missions) and bus.

The Moog Spacecraft bus is an energy-efficient small spacecraft platform designed for operation in LEO and beyond. Its compact design with no deployables eliminates jitter while improving pointing accuracy; and its agile platform offers excellent performance for telescope-based missions.

Telemetry

Telemetry is the practice of collecting information from remote or inaccessible locations and transmitting it back to a control center for analysis and review. Engineers use this data to estimate performance and assess equipment condition as well as schedule activities remotely.

The spacecraft bus is a collection of technological mechanisms designed to support the operation of space vehicles in orbit. It consists of subsystems for power, pointing, tracking and communication. All are engineered to withstand harsh space environments while remaining connected with ground control centers.

LADEE spacecraft bus is constructed on NASA’s Modular Common Spacecraft Bus (MCSB). This standardized architecture makes the bus easy to assemble for various missions, as well as supporting hosting of additional payloads onboard (known as “hitchhiking”) as a practice that helps lower launch costs and launch times for small satellite missions.

Command

A spacecraft bus serves as the structural framework for satellites, housing payloads and avionics to control them all. Additionally, it serves as the power subsystem which generates electrical energy for observations as well as stores, compresses, and transmits science data back to Earth.

Command and Data Handling (C&DH) subsystem comprises both the computer that runs the spacecraft as well as all associated electronics that enable data transportation between components of the satellite. Other subsystems rely on C&DH for responding to ground controller tele-commands from this system.

C&DHs must be capable of receiving and processing both real-time commands (RTCs) and stored sequence commands (SSC). An SSC file contains commands or calls to on-board scripts with time tags indicating when each should run.

Time distribution

A spacecraft bus is a standardized platform used to house and support satellite primary systems and subsystems. Designed to withstand launch pressures as well as space’s harsh environment, its purpose is to accommodate structures and mechanics subsystems; Command & Data Handling (C&DH), Communication antenna systems and antenna arrays; Electrical power system; Propulsion System and Attitude control System among others.

Most medium and large-scale satellites use central computer architectures that delegate analogue and discrete digital data acquisition and actuator control to remote terminal units connected via a system bus to their onboard computer. But for smaller satellites like CubeSats, increasingly distributed architectures are being implemented to allow teams more time to focus on creating an appropriate payload for the mission.

Reliability

The onboard bus serves as the backbone for transmitting commands and telemetry between spacecraft subsystems, so its reliability must be assured against possible failures while being capable of transmitting time data accurately and with sufficient precision.

A modular bus design strikes a balance between minimal part count and part complexity. To create modular modules with no more than 13 parts per section, 3D composite layup is used.

Reducing the number of mechanical joints and fasteners reduces nonrecurring costs while speeding assembly, test, and launch campaign times. Furthermore, this platform can accommodate medium to heavy lift launch vehicles for optimal reliability of large satellite missions in cis-lunar orbit.