Attachment J-2 MAV IMU Specifications 08 April 2021.pdf

ES31-SPEC-002

George C. Marshall Space Flight Center Revision 2.0 Marshall Space Flight Center, Alabama 35812 EFFECTIVE DATE: 4/8/2021

INERTIAL MEASUREMENT UNIT (IMU)

SPECIFICATION

FOR

MARS ASCENT VEHICLE (MAV)

ENGINEERING DIRECTORATE

Space Systems Department

ES31

Mars Ascent Vehicle

Specification for Mars Ascent Vehicle Inertial Measurement Unit

Document No: ES31-SPEC-002 Version 3.0

Effective Date: 4/8/2021 Page 3 of 35

Contents

1 INTRODUCTION

1.1 PURPOSE

1.2 SCOPE

2 DOCUMENTS

2.1 ORDER OF PRECEDENCE

2.2 APPLICABLE DOCUMENTS

2.3 DEFINITIONS AND TERMS

2.4 ABBREVIATIONS AND ACRONYMS

3 COMPONENT REQUIREMENTS

3.1 ITEM DESCRIPTION

3.2 PERFORMANCE REQUIREMENTS

Resource Allocation Lifetime Gyro Error Characteristics Accelerometer Error Characteristics

3.3 IMU COMPONENT INTERFACES

Telemetry Operating Modes External Alignment

3.4 DESIGN, CONSTRUCTION, AND QUALITY

Class-A Mission Statement Material Selection and Usage Cabling and Connections Soldering Printed Circuit Boards Quality Management Electrostatic Discharge Consideration Electrical Grounding Part Marking and Identification Software

3.5 ENVIRONMENTS

Transportation and Storage Environment Earth Launch Environments In-Space Environments

3.6 CLEANLINESS

Planetary Protection

4 DELIVERY

4.1 UNITS REQUIRED

Flight Unit Spare Flight Unit Qualification and Engineering Unit Flight Test Units

4.2 INTERFACE DOCUMENTATION

Mechanical Interface Electronic Interface Data Interface

4.3 CERTIFICATE OF COMPLIANCE

5 VERIFICATION

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5.1 VERIFICATION METHODS

Inspection Analysis Test Demonstration

5.2 VERIFICATION PHASES

Qualification (Q) Acceptance (A) Both (B)

5.3 TEST REQUIREMENTS

Test Factors Test Tolerances Test Restrictions

5.4 VERIFICATION CROSS REFERENCE MATRIX

5.5 REQUIRED TESTS

EMI Requirements Verification EMI Qualification by Similarity Test Data

6 PREPARATION FOR UNIT DELIVERY

6.1 METHODS OF PRESERVATION AND PACKAGING

Packaging Hardware Hardware Protection Monitoring Devices Marking for Shipment

APPENDIX A: VERIFICATION CROSS REFERENCE MATRIX REQUIREMENTS

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TABLES

Table 1: Applicable Documents Table 2: Transportation Load Factors Table 3: In-Space Mechanically Induced Vibration Table 4: In-Space Acoustically Induced Vibration Table 5: In-Space Shock Table 6: In-Space Radiation Table 7: Qualification and Acceptance Test Factors Table 8: Test Tolerances

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1 INTRODUCTION

1.1 Purpose

The National Aeronautics and Space Administration (NASA) George C. Marshall Space Flight Center (MSFC) is pursuing procurement of an Inertial Measurement Unit (IMU) for a Mars Ascent Vehicle (MAV). As a part of the Mars Sample Return Campaign, the MAV will transport Mars regolith samples from the Martian surface into orbit for rendezvous with an awaiting spacecraft.

Because the IMU will be used to propagate the launch vehicle attitude and support vehicle guidance during the ascent from Mars surface, the IMU will be considered a mission critical sensor assembly. Consequently, the IMU must provide uninterrupted measurement data (for a continuous period of up to 8 hours) and offer high reliability and robustness against adverse space environments. Additionally, the Mars Sample Return campaign will be classified as a NASA flagship mission, and therefore warrants critical sensor assemblies (such as the IMU) that are already space-qualified or can be space qualified through a judicious selection of high reliability and traceability of parts, qualified processes, and appropriate test campaigns in the desired timeframe.

The MAV is a two-stage vehicle and will require at least one IMU. Each IMU will be an integrated three-axis unit sensing both angular rates as well as linear accelerations about each axis. The IMU will be capable of meeting all the performance requirements after a minimum period of eight (8) years post-delivery. After a brief storage period and integration to the vehicle, the IMU would be required to tolerate environments of Earth launch, 2.5 years of deep space cruise, Entry, Descent, and Landing (EDL), and a storage period of up to two (2) years on the Martian surface. The IMU will be used for pre-flight gyrocompassing on the surface of Mars to obtain an accurate initial attitude solution. It can be assumed that there would be no external resources for in-flight or Martian surface recalibrations of the IMU. Note that the IMU will be in an unpowered state for a majority of the cruise except for short durations during health check-outs. The supplier will be responsible for the design, development, manufacture, testing, qualification and delivery of a fully calibrated IMU assembly and subsequent flight, flight spare, and any flight test units as needed.

1.2 Scope

This specification describes the electrical, mechanical, environmental, and verification testing requirements for a space-qualified 3-axis, Inertial Measurement Unit solution for the NASA Mars Ascent Vehicle.

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EM Engineering Model EMC Electromagnetic Compatibility EMI Electromagnetic Interference g Standard gravity on Earth (~9.80665 m/s2) GNC Guidance Navigation and Control grms g root-mean-square Hz Hertz I Inspection IBIT Initialization Built-In Test ICD Interface Control Document IMU Inertial Measurement Unit IPA Isopropyl Alcohol JPL Jet Propulsion Laboratory kg kilogram kPa Kilopascal LET Linear Energy Transfer LPT Limited Performance Test LVDS Low-Voltage Differential Signaling m Meter - SI base unit for length MAV Mars Ascent Vehicle MICD Mechanical Interface Control Document MeV Megaelectronvolt mg Milligram MPE Maximum/Minimum Predicted Environment MPT Maximum/Minimum Predicted Temperature mil Thousandth of an Inch mm Millimeter ms Millisecond MSFC Marshall Space Flight Center MSR Mars Sample Return MTTF Mean Time To Failure N/A Not Applicable NASA National Aeronautics and Space Administration

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OCM Original component Manufacturer PSD Power Spectral Density PP Planetary Protection PWS Performance Work Statement Q Qualification Unit Only Rad Radiation Absorbed Dose RDF Radiation Design Factor sec Second- SI base unit for time SI International System of Units SPL Sound Pressure Level T Test TBD To Be Determined TBR To Be Reviewed TBS To Be Selected TID Total Ionizing Dose VCRM Verification Cross Reference Matrix VDC Volts Direct Current V&V Verification and Validation µ Micron

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3 COMPONENT REQUIREMENTS

3.1 Item Description

The Inertial Measurement Unit (IMU) should provide three axis incremental angle and incremental velocity information based on the use of flight-qualified, high grade inertial sensors. The IMU is intended for use in the Guidance Navigation and Control (GNC) subsystem as a high accuracy, fine resolution inertial navigation sensor.

3.2 Performance Requirements

Resource Allocation

3.2.1.1 Mass

The delivered IMU assembly shall be less than or equal to the target mass of 4.5 kg.

Special Statement on Mass: Due to the nature of the mission, mass is a significant driver for vehicle performance, and the desired mass is less than 4.2 kg. If the desired mass can be met or reduced further with additional engineering, the supplier should provide mass saving design options, configurations, and/or modifications to the IMU, and their subsequent impacts to cost and schedule.

3.2.1.2 Envelope Dimensions

The delivered IMU assembly shall occupy a physical envelope equal to or less than the target of 240mm (Length) x 240mm (Width) x 170mm (Height).

Special Statement on Volume: Due to the nature of the mission, volume is a driver for vehicle performance. If the target volume can be met or reduced further with additional engineering, the supplier should provide mass savings design options, configurations, and/or modifications to the IMU, and their subsequent impacts to cost and schedule.

3.2.1.3 Power

3.2.1.3.1 Nominal Power

The IMU shall have a nominal (continuous) power consumption of less than or equal to 36 W over the operating range in Section 3.2.1.3.5.

3.2.1.3.2 Inrush Power

a) The inrush power shall occur within 60 seconds after unit power on.

b) The inrush power shall not exceed 250W.

c) The inrush power duration shall be shorter than 10 ms.

3.2.1.3.3 Peak Power

The peak power shall not exceed 50W after 60 seconds of operation over the operating range in Section 3.2.1.3.5.

3.2.1.3.4 Power Isolation

The primary power line shall be isolated from the chassis by at least 1 megaohm.

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3.2.1.3.5 Operating Voltage

While powered on, the IMU shall operate within the bus voltage range of +24 to +35 VDC.

Special Statement on Voltage: If lower voltage(s) can be used to support mass savings, the supplier should list such design options, configurations, and/or modifications to the IMU and their subsequent impacts to cost and schedule.

Lifetime The IMU shall be capable of meeting all performance requirements for a minimum period of eight

(8) years post-delivery.

Gyro Error Characteristics The IMU’s gyroscope specifications are provided in this section. All values listed are after exposure to environments as defined in Section 3.5 at the end of the mission life as defined in Section 3.2.2. If the specification cannot be met, the supplier should provide the value that can be met, or a delta to the requirement. Accurate attitude initialization via gyrocompassing is critical for MAV- the vender should take this into account when assessing the requirements.

3.2.3.1 Gyro Dynamic Input

The IMU shall meet all performance specifications at inertial rates between 0 degrees per second and +/- 150 degrees per second.

Special Statement on Gyro Dynamic Input: It is possible that higher gyro dynamic input may be needed for any flight test units. The supplier should list the maximum gyro dynamic input that the IMU can be subjected to with limited performance degradation.

3.2.3.2 Gyro Bias Repeatability

The gyro bias repeatability error shall be less than 0.008 degrees per hour 1-sigma.

3.2.3.3 Gyro Bias Stability

The gyro bias error stability, over 8 hours and over the operational temperature range, shall be less than 0.005 degrees per hour 1-sigma.

3.2.3.4 Gyro Scale Factor Error Repeatability

The gyro scale factor error repeatability shall be less than 10 parts per million 1-sigma.

3.2.3.5 Gyro Scale Factor Error Stability

The gyro scale factor error stability, over 8 hours and over the operational temperature range, shall be less than 1.0 parts per million 1-sigma.

3.2.3.6 Gyro Angular Random Walk

The gyro angular random walk shall be less than 0.005 degrees per root hour 1-sigma.

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3.2.3.7 Gyro Readout Noise

The gyro readout noise shall be less than 0.001 degrees 1-sigma.

Accelerometer Error Characteristics The IMU’s accelerometer specifications are provided in this section. All values listed are after exposure to environments as defined in Section 3.5 at the end of the mission life as defined in Section 3.2.2. If the specification cannot be met, the supplier should provide the value that can be met, or a delta to the requirement. Accurate attitude initialization via gyrocompassing is critical for MAV- the vender should take this into account when assessing the requirements.

3.2.4.1 Accelerometer Dynamic Input

The accelerometers shall meet all performance specifications during dynamic accelerations of at least 15 g’s on any axis in any direction.

Special Statement on Accelerometer Dynamic Input: It is possible that higher accelerometer dynamic input may be needed for any flight test units. The supplier should list the maximum accelerometer dynamic input that the IMU can be subjected to with limited performance degradation.

3.2.4.2 Accelerometer Bias Repeatability

The accelerometer bias repeatability shall be 40 micro-g or less 1-sigma.

3.2.4.3 Accelerometer Bias Stability

The accelerometer bias stability, over a period of 8 hours and over the operational temperature range, shall be less than 5 micro-g 1-sigma.

3.2.4.4 Accelerometer Scale Factor Error

The composite accelerometer scale factor error shall be less than 50 parts per million 1-sigma.

3.2.4.5 Accelerometer Velocity Random Walk

The accelerometer velocity random walk shall be less than 30 millimeters per second per root hour 1-sigma.

3.2.4.6 Accelerometer Readout Noise

The accelerometer readout noise shall be less than 1.0 millimeters per second 1-sigma.

3.2.4.7 Center of Navigation

The IMU center of navigation shall be known and documented to within +/- 0.3 mm.

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3.3 IMU Component Interfaces

Telemetry

3.3.1.1 Data

The IMU telemetry shall provide total and/or incremental velocity and total and/or incremental angular measurements.

3.3.1.2 Channel Latency

The latency of the data from measurement to transmission of each channel shall not exceed 6 ms prior to any filtering.

3.3.1.3 Health

The IMU shall provide health and status telemetry, including results of the Initialization Built-In Test (IBIT).

3.3.1.4 Output Sample Rate

The IMU shall supply the data specified in Section 3.3.1.1 at no less than 100 Hz.

3.3.1.5 Output Sample Repetition

The IMU shall generate a unique measurement in each sample without repeating or extrapolating the previous value.

3.3.1.6 Coning and Sculling Compensation

The IMU shall output gyro and accel data that has been compensated for coning and sculling motions.

3.3.1.7 Saturation Direction

The IMU shall output the saturation direction in the event that an axis input rate or acceleration has reached the saturation limit.

3.3.1.8 Saturation Recovery

The IMU shall be able to recover from saturation without a power reset.

3.3.1.9 Communication Protocol

The IMU shall output data using a differential RS422 output interface using no more than three

(3) separate differential RS422 lines.

Operating Modes

3.3.2.1 Start-Up

The IMU shall have a Startup Operating Mode that includes instrument warm-up, initialization, loading pre-stored calibration coefficients, and IBIT.

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3.3.2.2 Ready

The IMU shall have a Normal Operating Mode which includes sampling instrument data, compensating for instrument errors, conduct simple fault detection, and outputting data, health, and status information.

3.3.2.3 Initialization time

The IMU shall automatically transition from start-up mode to normal mode and begin outputting data in accordance with Section 3.3.1 within 60 seconds after beginning to receive power in accordance with Section 3.2.1.3.

External Alignment

3.3.3.1 Optical Alignment Device

The IMU shall have two perpendicular optical mirrors or an optical reference cube to allow for external alignment measurement of the IMU.

3.3.3.2 Optical Alignment Device Size

The available area of the optical reference surfaces shall be greater than 2.5 cm2.

3.3.3.3 Optical Alignment Device Availability

At least two perpendicular surfaces of the optical reference device shall be available for alignment measurement without affecting the base integrity of the IMU.

3.3.3.4 Alignment Accuracy

The alignment of the optical alignment device to the sensor frame shall be known to within 30 arcsec in each axis after exposure to all environments.

3.3.3.5 Alignment Stability

The IMU mounting system shall maintain the orientation of the sensor frame within 30 arcsec in each axis of its original placement with respect to the mounting surface.

3.4 Design, Construction, and Quality

Class-A Mission Statement The Mars Sample Return mission has been designated as a Class-A mission. NASA defines a Class-A mission as one in which failure would have extreme consequences to public safety or high priority national science objectives. In order to meet Class-A requirements, space-qualified Grade 1 EEE parts should be used. Grade 1 is a classification which designates EEE parts of the highest practical quality standards.

3.4.1.1 Part Reliability, Quality Assurance, and Application Analysis

a) The supplier shall select and procure Grade 1 EEE parts in accordance with MSFC-STD-

3012 Table V. For exceptions where Grade 1 parts are not available, the supplier shall use Grade 2 parts with a waiver and project approval.

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b) All EEE parts in the IMU shall be procured only from the original component manufacturers (OCM) or their authorized distributors.

c) The MSFC EEE Parts organization shall review and approve all EEE parts selections for the IMU.

d) The IMU shall have a reliability of 20000 hours MTTF in a ground fixed environment verified by analysis using MIL-HDBK-217FN2.

e) An EEE parts applications derating analysis shall be performed by the supplier and submitted to MSFC for review. Project approval shall be obtained prior to use of a part in an application where derating requirements are not met.

Special Statement on Grade 1 Parts: The supplier should provide design options, configurations, and/or modifications to the IMU to meet this requirement if not already met, and their subsequent impacts to cost and schedule. If specific components fall below this quality standard and cannot be modified, include this in the response.

3.4.1.2 Traceability & Data Requirements

a) The supplier shall have a system for providing traceability for all EEE parts used in the IMU.

b) The IMU delivery shall provide the capability for tracing a specific part lot through all phases of kitting, fabrication, assembly, test, and delivery, identifying which equipment contains specific part lots.

c) The supplier shall submit an As-Designed EEE parts list in accordance with MSFC-

STD-3012 to the MSFC EEE parts organization for review and approval prior to PDR.

Changes to the baseline As-Designed EEE Parts List shall be monitored and controlled at all levels of procurement, test, and fabrication to ensure the prompt identification, reporting, review, and disposition (approval/disapproval) of changes.

d) The data shall be submitted in electronic format for MSFC review as specified in the

PWS.

e) The supplier shall submit an As-Built EEE parts list in accordance with MSFC-STD- 3012 for the deliverable end-item.

Material Selection and Usage

a) The supplier shall select materials for their intended usage applications in accordance with NASA-STD-6016.

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b) The supplier shall provide a Materials Identification and Usage List with content as specified in NASA-STD-6016.

Cabling and Connections

a) The IMU wiring, wiring harnessing, and electronic connections shall be in accordance with

NASA-STD-8739.4A.

b) The IMU shall have Class R bonding in accordance with NASA-STD-4003A.

Soldering All soldering in the IMU shall be in accordance with IPC-J-STD-001ES.

Printed Circuit Boards The IMU shall meet the requirements of IPC-6011 and IPC-6012 for printed circuit boards and printed circuit board assemblies.

Quality Management The IMU shall have a quality management system compliant to SAE-AS9100D and MPR-8730.3.

Electrostatic Discharge Consideration The IMU shall be protected from electrostatic discharge (ESD) and control methods to prevent damage to ESD sensitive components during all phases of receiving, storage, manufacturing, assembly, operation and test in accordance with ANSI/ESD S20.20 and MSFC-STD-3012 Paragraph 5.8.1.

Electrical Grounding The IMU shall contain provisions for a ground connection from the component chassis for connection to an external conductive structure.

Part Marking and Identification

3.4.9.1 Parts List

The supplier shall provide a parts list to confirm part reliability as specified in the PWS.

3.4.9.2 Parts Marking

All parts used in the IMU shall be marked in accordance with the component specification and/or engineering design documentation to ensure configuration management of subassemblies and part traceability.

3.4.9.3 Serialization

All non-standard parts and same configuration parts shall be serialized with a unique serial number.

3.4.9.4 Records

Records shall provide capability for backwards traceability to identify fabrication, inspection, processing, test, and operating records with traceability to the procurement documents.

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Software The IMU software shall be developed in accordance with NPR 7150.2C for a Class B safety critical development effort.

3.4.10.1 Embedded Software Version

The IMU shall provide a software/firmware version indicator that is readable in the output message or in documentation.

3.4.10.2 Inadvertent Software Loads

The IMU shall have features to prevent accidental software loads.

3.4.10.3 Memory Refresh

Any need for periodic refresh of non-volatile memory along with its trigger mechanism shall be explicitly identified.

3.5 Environments

The MAV-012 document defines environments for the MAV mission, and the supplier may reference MAV-012 as a guide in addition to the environments in this section.

Special Statement on Environments: If the specification cannot be met, the supplier should provide the value that can be met, or a delta to the requirement. Additionally, in cases the specification is not met, the supplier should provide options, configurations, and/or modifications to the IMU to meet the specification, and their estimated impacts to cost and schedule.

Transportation and Storage Environment The following requirements define transportation and storage of the IMU on Earth for ground operations.

3.5.1.1 Transportation and Storage Load Factors

The IMU shall meet the performance requirements of Section 3.2 after exposure to the transportation loads as defined in NASA-STD-5002A Appendix A and below in Table 2.

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3.5.2.2 Earth Launch Acoustic

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the acoustic environments derived from MAV-012 or the launch service payload user’s guide.

3.5.2.3 Earth Launch Shock

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the shock environment derived from MAV-012 or the launch service payload user’s guide.

3.5.2.4 Earth Launch Radio Frequency

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the radio frequency environment derived from MAV-012 or the launch service payload user’s guide.

3.5.2.5 Earth Launch Pressure

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the pressure environment derived from MAV-012 or the launch service payload user’s guide.

3.5.2.6 Earth Launch Temperature

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the temperature environment derived from MAV-012 or the launch service payload user’s guide

3.5.2.7 Earth Launch Humidity

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the humidity environment derived from MAV-012 or the launch service payload user’s guide.

3.5.2.8 Earth Launch Aerothermal Heating

The IMU shall meet the performance requirements of Section 3.2 after being subjected to the temperature environment derived from MAV-012 or the launch service payload user’s guide.

In-Space Environments The following describes the environmental requirements for the IMU during transportation to Mars, EDL to the Martian surface, storage on the surface of Mars, and ascent from the Martian surface through completion of the mission.

Special Statement on In-Space Environments: The overall in-space environments for MAV have yet to be finalized, and a preliminary estimate is shown. The supplier should take this into account when assessing these requirements.

3.5.3.1 In Space Loads

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to 15 g’s in any direction.

3.5.3.2 In-Space Mechanically Induced Vibration

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to the mechanically induced random vibration defined in Table 3. This table represents a 95/50 MPE.

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Special Statement on Cold Storage Temperature: Future MAV design modifications may allow for long-term cold storage at a temperature higher (warmer) than -40 °C. The supplier should include an assessment of any effects of this change, including impacts to cost and schedule.

3.5.3.7.2 In-Space Operational Temperature

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to temperatures of -25 °C and +55 °C.

3.5.3.7.3 In-Space Operational Temperature Ramp Rate

3.5.3.7.3.1 Temperature Ramp Rate During Pre-Launch

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to a maximum temperature ramp rate of ± 0.5 °C/minute.

Special Statement on Temperature Ramp Rate During Pre-Launch: This requirement is a result of preliminary analysis and will depend on the specific IMU, and future MAV design modifications may allow for a temperature ramp rate of lower than ±0.5 °C/minute. The supplier should include an assessment of any effects of this change, including impacts to cost, schedule, and performance.

3.5.3.7.3.2 Temperature Ramp Rate During Ascent

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to a maximum temperature ramp rate of ± 2 °C/minute.

Special Statement on Temperature Ramp Rate During Ascent: If the IMU cannot meet all the performance requirements during a ±2 °C/minute temperature ramp rate, the supplier should provide the predicted performance while undergoing this thermal ramp rate. This requirement is a result of preliminary analysis and will depend on the specific IMU, and future MAV design modifications may allow for a temperature ramp rate of lower than ±2 °C/minute. The supplier should include an assessment of any effects of this change, including impacts to cost, schedule, and performance.

3.5.3.8 In-Space Radiation

3.5.3.8.1 In-Space Radiation Dosage

The IMU shall meet the performance requirements of Section 3.2 during and after exposure to the radiation environments defined in Table 6 behind 100 mils Al shielding with a Radiation Design Factor (RDF) of 2 during cruise to mars, conservatively 2.65 earth years, and on the surface of mars for conservatively 2 years.

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Special statement on Particulate and Molecular Contamination: Care needs to be exercised during the early design phase to limit or preclude materials that will generate or release contaminants (particulate and molecular) that may adversely affect system performance. Potential contaminants from materials include corrosive products, flaking due to friction, aging, or poor adhesion, and outgassing. The approach is to minimize contamination from materials and material processing operations by careful material selection. General design guidelines are as follows:

Nonmetallic materials that outgas under ambient conditions will not be used.

Materials that tend to produce particles by dusting, flaking, or abrading will be avoided.

Use corrosion-resistant materials.

Avoid fasteners and fastening concepts with entrapment areas.

Avoid inaccessible or "hidden" areas.

Do not use cadmium, zinc, or unfused electrodeposited tin.

3.6.1.3 Cleanability

3.6.1.3.1 Sensitive Surfaces

If any surfaces are not cleanable with IPA and polyester wipes they shall be identified on the

MICD.

3.6.1.3.2 Sensitive Surface Cleaning Methods

Alternate cleaning methods shall be identified and appropriate documentation provided for any surfaces that are not cleanable with IPA.

3.6.1.4 Non-Metallic Materials

All non-metallic material usage shall be in accordance with NASA-STD-6016 and MAV-CC-PP- Plan.

3.6.1.5 Foreign Object Debris

The IMU shall be manufactured, transported, and tested in accordance with the FOD prevention program that conforms to NAS 412 as specified in NASA-STD-6016.

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4 DELIVERY

4.1 Units Required

Flight Unit The supplier shall provide one flight unit as specified in the PWS.

Spare Flight Unit The supplier shall provide one spare flight unit as specified in the PWS.

Qualification and Engineering Unit The supplier shall provide one unit to be used as an engineering unit, which is flight-like in form, fit, and function, and are quality-controlled as specified in the PWS. This unit will undergo acceptance testing and any qualification testing that is needed.

Flight Test Units The supplier shall be capable of providing up to three flight test units if the purchaser deems necessary as specified in the PWS.

4.2 Interface Documentation

Mechanical Interface The mounting interface shall be defined in a Mechanical Interface Control Document (MICD) as specified in the PWS.

Electronic Interface The electrical interface shall be defined in an Electrical Interface Control Document (EICD) as specified in the PWS.

Data Interface The data interface shall be defined in a Data Interface Control Document (DICD) as specified in the PWS.

4.3 Certificate of Compliance

The supplier shall submit a Certificate of Compliance (COC) signed by responsible representative of the company, stating that all materials, processes, and/or finished components supplied under this procurement meet the applicable specifications.

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5 VERIFICATION

The supplier shall conduct a verification program that demonstrates the hardware design is qualified and meets all requirements contained in this document. The supplier shall provide documentation showing conformance to this specification.

5.1 Verification Methods

Verification methods are the methods by which the requirements in Section 3 are to be verified.

One or more of the following methods will be used:

Inspection Verification by inspection is the physical evaluation of hardware and/or documentation/drawings to verify design features. Inspection is used to verify construction features, workmanship, dimension and physical condition, such as cleanliness, surface finish, and locking hardware.

5.1.1.1 Visual Inspection

Visual inspection of the physical component shall be performed by a qualified inspector to certify that the component has the properties/configuration specified in the requirement.

5.1.1.2 Physical Measurement

Physical measurement of component properties (i.e. mass, dimensions, etc.) shall be performed by a qualified inspector to demonstrate the component meets specific requirement.

Analysis Verification by analysis will be used to confirm design margins when required. Also, when the particular tests required for verification are impractical, risky, unacceptably long, or prohibitively expensive, analysis may be used instead of testing, as noted in the verification matrices. Analysis, including simulations where applicable, can also be used to verify that the IMU and its components will perform as expected under worst-case conditions.

Test Verification by test includes, but is not limited to, the evaluation of performance by use of special equipment or instrumentation and the application of established principles and procedures to determine compliance with requirements.

Demonstration Verification by demonstration is the use of actual demonstration techniques in conjunction with requirements such as operational performance, serviceability, accessibility, transportability, human engineering features, and display data.

5.2 Verification Phases

Verification phases are the phases in which the requirements in Section 3 are to be verified.

Requirements will be verified in one or more of the following phases:

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Performance Testing Mass Properties Static Load/Strength Random Vibration Proof Pressure Shock Electromagnetic Compatibility Thermal Vacuum Bake-Out Thermal Vacuum

Although specific profiles for performance tests are TBS, the supplier can consult SMC-S-016 as a guide.

EMI Requirements Verification EMI verifications shall be by test in accordance with MIL-STD-461G guidelines and performed in accordance with a JPL approved Test Procedure containing the format and content specified in Data Item Description (DID) DI-EMCS-80201. The EMI test results shall be documented in an EMI Test Report (EMITR) in accordance with DID DI-EMCS-80200 and submitted to MSFC for review approval.

EMI Qualification by Similarity Legacy hardware qualified to other revisions of MIL-STD-461 (i.e., MIL-STD-461C) may be found acceptable by requirements comparison review and analysis and/or additional special tests.

Test Data Pertinent test data shall be maintained in a quantitative form to permit the evaluation of performance under the various specified test conditions; pass or fail statements alone are insufficient. The test data should also be compared across major test sequences for trends or evidence of anomalous behavior.

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6 PREPARATION FOR UNIT DELIVERY

6.1 Methods of Preservation and Packaging

Unless otherwise specified in the contract or purchasing order, IMUs procured to this specification shall be packaged, packed, and marked for shipment as specified herein. A copy of the supplier’s handling/transportation and safety procedures and cleanliness certification shall be included with the delivery. The supplier can baseline NPR 6000.1H and NASA-HDBK 8739.21 as a guide, adhering to additional planetary protections levied from Section 3.6.1.

Packaging Hardware Materials and accessories used in the packaging, handling, shipping, and storage that have intimate contact with the part or assembly shall be free of general contamination and shall maintain the specified cleanliness levels of the hardware. Protective and packaging materials shall be chosen based on their ability to adequately resist shedding of particulate and penetration by tearing or piercing caused by forces either external or internal during normal handling operations. Parts and assemblies shall be packaged in a manner that will preclude any chance of one item making contact with another during normal handling operations.

Hardware Protection

6.1.2.1 Coverings

The IMU shall be provided with protective covering to prevent contamination during transportation outside clean areas and where necessary to protect against damage in handling. All covering/packaging material shall either meet or exceed the contamination requirements of the hardware which it will contain and adhere to ESD requirements per NPR 6000.1H and NASA- HDBK 8739.21. Generally, for Planetary Protection, parts will be double bagged with each layer sealed, and then placed inside a protective shipping container.

6.1.2.2 Caps and Plugs

All connections to the IMU shall be protected with caps, plugs, covers or other protective barriers.

Such items shall be highly visible, red in color or shall have attached highly visible red colored streamers to ensure that they are easily identified under casual observation. Caps and plugs shall be cleaned and meet the required hardware cleanliness levels before use.

6.1.2.3 Electrostatic Discharge

Electrostatic sensitive hardware shall be packaged and marked in accordance with NPR 6000.1H and NASA-HDBK 8739.21. All ESD protective coverings shall be properly sealed with proper ESD labeling.

6.1.2.4 Shipping and Storage Containers

Contamination control protocols shall be in place prior to planetary protection cleaning and biological cleanliness verification to include foreign object debris mitigation and a visibly clean surface at a minimum.

Shipping containers shall allow for solvent cleaning (i.e. isopropyl alcohol) by physical wiping on all internal and external surfaces.

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Surface finishes shall be smooth and materials should not be porous.

Painted or surface finishes shall be not easily removed or flake off to minimize particulates (must be able to withstand several cleaning events per mission).

Shipping containers shall be complaint for PP verification using damp water wipe on any surfaces.

Both interior and exterior surfaces shall not corrode when challenged with biological microbial reduction agents (e.g. solvent cleaning).

Container shall be sealed with a physical barrier (e.g. mechanical seal, tape) between the container mating surface points to prevent ingestion of exterior air and particulates at all points.

Containers shall have appropriate V&V conducted to demonstrate preferential venting paths through HEPA or sintered filtered ports.

Monitoring Devices Instrumentation for monitoring or recording in-transit environments (e.g., vibration, shock, temperature, etc.), shall be specified and approved by NASA prior to implementation.

Marking for Shipment Interior and exterior containers shall be marked and labeled in accordance with NPR6000.1 and MIL-STD-129 including precautionary markings necessary to ensure safety of personnel and facilities and to ensure safe handling, transport, and storage. NASA Critical Item Label (NASA Form 1368) shall be applied in accordance with NPR6000.1. The following identification information on interior and exterior containers shall include as a minimum:

Attn/Recipient Contact Number NASA Contract Number Item Name Seller’s Part Number Serial Number Seller’s Name Seller’s CAGE Code Quantity Cleaning Marking Gross Weight