Sensing & Acquisition • Data Management • Analysis & Synthesis • Planning & Prosecution • Common Operating Infrastructure • Common Execution Infrastructure

Sensing and Acquisition

The Sensing and Acquisition SN performs instrument management, mission execution, and data acquisition tasks. The Instrument device model consists of one or more physical sensors or actuators, and is represented in the CI by a logical device, the Instrument Agent. The physical device provides sensor data and status information to the Instrument Agent, and receives configuration information and commands from it. Each Instrument Agent has an Instrument Supervisor that is responsible for monitoring the state of health of the Instrument. Each platform has a Platform Agent that is responsible for controlling all devices on that platform. Observatory Management is responsible for coordinating all observatory resources to ensure their safe operation. The Exchange service is a projection of COI capabilities, with the main purpose of establishing a publish-subscribe model of communication that ensures distributed data delivery to all end-points. It appears in all SNs.

The Instrument Agent is responsible for translating commands from the Platform Agent to the Instrument, event handling, acquiring data from the Instrument, managing the state of the Instrument, providing direct access (e.g., ssh) to the Instrument, and updating the Instrument clock from an external source. The Instrument Supervisor receives status information and observed data from the Instrument Agent and performs diagnostics and instrument state estimation. It is responsible for instrument fault detection and recovery. Information about instruments is kept in ans; instruments have associated metadata that can be invariant (e.g., model, manufacturer, specs) or variant (e.g., location). Observatory Management is responsible for registering the invariant instrument metadata, whereas the Instrument Agent is responsible for publishing the variant instrument metadata.

The Platform Agent is responsible for registering and validating instruments and detecting resource conflicts at runtime or at registration. It schedules data acquisition as specified in the observation plan produced by the Planning and Prosecution SN or according to the commands received directly from the operators via the Observatory Management node.

Observatory Management protects the assets of the observatory, and therefore is responsible for fulfillment, assurance, and reconciliation. Fulfillment services include resource activation, configuration, simulation, and testing. Assurance services include state of health monitoring, fault detection and recovery and quality assurance. Reconciliation services include billing and resource conflict mediation. Observatory Management also provides users with the capability to configure the calibration of their instruments and the processing steps to produce calibrated and QC’d data products.