The Data Management System (DMS) is in charge of
- Telecommand distribution to the whole spacecraft
- Telemetry data collection from the spacecraft systems and payload and formatting of the collected data
- Overall supervision of spacecraft and payload functions
The DMS is based on a standard On-Board Data Handling (OBDH) bus architecture enhanced by high rate serial data links connecting the Control and Data Management Unit (CDMU) processors with the Solid State Mass Memory (SSMM) and Attitude and Orbit Control System (AOCS) Interface Unit. The OBDH bus is the data route for platform and payloads data acquisition and commands distribution via the Remote Terminal Unit (RTU).
The DMS includes 4 identical Processor Modules (PM), two located in each CDMU. Two processor modules are dedicated to the DMS, and two to the AOCS. The PM selected for the DMS function acts as the bus master. It is responsible for managing the platform's communications, power, and thermal control systems. The PM selected as the AOCS computer is in charge of all sensors, actuators, High Gain Antennas (HGAs) and the Solar Array Drive Electronics (SADE). A telecommand decoder and Transfer Frame Generator (TFG) are included in each CDMU.
The Solid State Mass Memory (SSMM) is used for data storage and has a capacity of twelve gigabits. It is coupled to the two DMS processors, the TFGs, and the VIRTIS and VMC instruments. It stores science and global housekeeping telemetry packets.
The Control and Data Management Units (CDMU) control ground command reception and execution, on-board housekeeping and science data telemetry storage, and formatting of stored data for transmission. The on-board data management functions, control laws processing and execution of on-board control procedures are also performed by the CDMUs.
Data transfer with other Data Handling units is implemented using a redundant OBDH data bus and IEEE-1355 serial links. Two Interface Units connect those links with other spacecraft units. The AOCS Interface Unit deals with the AOCS sensors, reaction wheels, solar array drive and propulsion transducers and actuators. The RTU interfaces with the other spacecraft systems and the instruments.
Last Update: 24 May 2007