HMI Top Level Requirements Rock Bush Stanford HMI Program Manager RBush@solar.stanford.edu

Requirements Overview Basis of Requirements Requirements Sources Draft HMI Functional Specifications

Basis of Requirements HMI Science Objectives HMI Observation Sequences Duration of mission Completeness of coverage HMI Science Data Products Roll accuracy Time accuracy (months) HMI Observation Sequences Duration of sequence Cadence Completeness data sequence Noise Resolution Time accuracy (days) HMI Observables Sensitivity Linearity Acceptable measurement noise Image stability Time rate (minutes) Orbit knowledge HMI Instrument Data Accuracy Noise levels Completeness of filtergrams Tuning & shutter repeatability Wavelength knowledge Image registration Image orientation jitter HMI Instrument Concept Mass Power Telemetry Envelope Subsystem requirements CCD: Thermal environment ISS: pointing drift rate, jitter Legs: pointing drift range

Basic Requirements Sources SDO Level 1 Requirements SDO Mission Requirements Document (MRD) Summary of spacecraft and instrument driving requirements HMI Instrument Functional Specification Top level HMI requirements – part of the HMI contract statement of work HMI Instrument Performance Document (IPD) Detailed HMI science drivers and flowdown to subsystem requirements SDO Mission Assurance Requirements SDO spacecraft and instrument requirements for design, fabrication, verification, etc. HMI Performance Assurance and Implementation Plan (PAIP) HMI implementation of the SDO MAR HMI to Spacecraft Interface Control Documents (HMI-S/C ICD) Ground System Interface Control Document

HMI Requirements The HMI Functional Specification is the contractual link between the SDO project office and the HMI development team. The Functional Specification documents the key instrument parameters needed to meet the HMI goals. The Draft Functional Specification is summarized in the next chart, and the verification will be discussed during the test and integration presentation. The Functional Specification is under review and will be finalized as part of the Phase C/D contract negotiations. The HMI Instrument Performance Document (IPD) details the HMI observations required to meet the science goals, and the derived subsystem design and performance requirements. The IPD contains three sections: Instrument observations required to meet the science objectives Instrument performance requirements needed to obtain the observations Detailed subsystem design specifications needed to obtain the specified performance The HMI Performance Document is modeled after the Michelson Doppler Imager Instrument Performance Specification.

HMI Functional Specifications Summary