DSG-SPEC-MECH-017,_Gateway_Program_Docking_System_Specification_(Public_Release).pdf

Revision: Initial Release (Draft) DSG-SPEC-MECH-017 Release Date: JUNE 30, 2019 Page: 2 of 57 Title: Gateway Docking System Specification

This document has been approved for public release per DAA STI # 65329 and TN #72185

DSG-SPEC-MECH-017

INITIAL RELEASE (DRAFT)

National Aeronautics and Space Administration RELEASE DATE: JUNE 30, 2019

GATEWAY DOCKING SYSTEM SPECIFICATION

(GDSS)

July 26, 2019

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REVISION AND HISTORY PAGE

Revision No.

Change No.

Description Release

Date

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TABLE OF CONTENTS

SECTION PAGE

1.0 INTRODUCTION

1.1 PURPOSE AND SCOPE

1.2 RESNSIBILITY AND CHANGE AUTHORITY

2.0 DOCUMENTS

2.1 APPLICABLE DOCUMENTS

2.2 REFERENCE DOCUMENTS

2.3 ORDER OF PRECEDENCE

3.0 GATEWAY DOCKING SYSTEM SPECIFICATION

3.1 GENERAL

3.1.2 ENGINEERING UNITS OF MEASURE

3.2 MATING INTERFACE DEFINITION

3.2.1 TRANSFER PASSAGEWAY

3.2.2 SOFT CAPTURE SYSTEM

3.2.3 HARD CAPTURE SYSTEM

3.2.4 ELECTRICAL BONDING

3.2.5 ACTIVE DOCKING SYSTEM INTERFACE COMPATIBILITY

3.2.6 RESERVED

3.3 DOCKING PERFORMACE

3.3.1 SOFT CAPTURE SYSTEM

3.3.2 HARD CAPTURE SYSTEM

3.4 RESOURCE TRANSFER UMBILICALS

3.4.1 RECTANGULAR UMBILICAL CONNECTORS

3.4.2 FLUID TRANSFER CONENCTORS

3.5 NAVIGATION AND ALIGNMENT AIDS

3.6 BERTHING

3.6.1 CAPTURE LATCH SYSTEM ACTUATION

3.6.2 SOFT CAPTURE SYSTEM SENSING

4.0 RESERVED

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APPENDIX

APPENDIX A - ACRONYMS AND ABBREVIATIONS AND GLOSSARY OF TERMS

APPENDIX B - OPEN WORK

APPENDIX C - VERIFICATION MATRIX

TABLE

TABLE 3.3.2.1-1 HCS MAXIMUM MATED LOADS

TABLE 3.3.2.1-2 HCS MATED LOAD SETS

TABLE 3.4.1.1-1 RUC PART NUMBER

TABLE 3.4.1.9-1A GDSS VV RUC PINOUTS (2 PAGES)

TABLE 3.4.1.9-2A GDSS VV RUC PINOUTS DEFINITIONS (2 PAGES)

TABLE 3.4.1.9-3A UNASSIGNED GDSS VV RUC PINOUTS

TABLE 3.4.1.9-1B GDSS HP RUC PINOUTS (2 PAGES)

TABLE 3.4.1.9-2B GDSS HP RUC PINOUTS DEFINITIONS (2 PAGES)

TABLE 3.4.1.9-3B UNASSIGNED GDSS HP RUC PINOUTS

TABLE 3.4.2.1-1 FTC PART NUMBER

TABLE B-1 TO BE DETERMINED ITEMS

TABLE B-2 TO BE RESOLVED ISSUES

FIGURE

FIGURE 3.2.3.2-1 HCS SEALING SURFACE

FIGURE 3.2.3.4.1-1 LOAD RESPONSE OF PASSIVE HOOK MECHANISM (INCLUDING

SPRING WASHER STACK)

FIGURE 3.4-1 UMBILICAL CONNECTOR KEEP-OUT ZONES

FIGURE 3.4.1-1 VV RUC

FIGURE 3.4.1-2 HP RUC

FIGURE 3.4.1.2-1 RUC ELECTRO-MECHANICAL ACTUATOR CONCEPT OF

OPERATION

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FIGURE 3.4.1.4.1-1 ELECTRICAL TRANSFER UMBILICAL CONNECTORS

FIGURE 3.4.1.4.4-1 RUC MATING OPERATION WITH ACTIVE PLUG

FIGURE 3.4.1.4.4-2 RUC MATING OPERATION WITH ACTIVE RECEPTACLE

FIGURE 3.4.1.5.1.1-1 PLUG RUC LATERAL COMPLIANCE IN X DIRECTION

FIGURE 3.4.1.5.1.1-2 PLUG RUC LATERAL COMPLIANCE IN Y DIRECTION

FIGURE 3.4.1.5.1.2-1 PLUG RUC ROTATIONAL COMPLIANCE ABOUT THE Z AXIS .. 26

FIGURE 3.4.1.5.2.1-1 RECEPTACLE RUC AXIAL COMPLIANCE

FIGURE 3.4.1.9-1A VV RUC RECEPTACLE (SOCKETS) - FRONT FACE

FIGURE 3.4.1.9-2A VV RUC PLUG (PINS) - FRONT FACE

FIGURE 3.4.1.9-1B HP RUC RECEPTACLE (SOCKETS) - FRONT FACE

FIGURE 3.4.1.9-2B HP RUC PLUG (PINS) - FRONT FACE

FIGURE 3.4.2.2-1 FTC ELECTRO-MECHANICAL ACTUATOR CONCEPT OF

OPERATION

FIGURE 3.4.2.4.1-1 FLUID TRANSFER UMBILICAL CONNECTORS – PASSIVE SIDE 39

FIGURE 3.4.2.4.3-1 CENTERLINE ANGULAR MOUNTING REQUIREMENTS

FIGURE 3.4.2.4.4-1 COOLANT RECEPTACLE FTC AXIAL MOUNTING POSITION

FIGURE 3.4.2.4.4-2 PROPELLANT RECEPTACLE FTC AXIAL MOUNTING POSITION 41

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1.0 INTRODUCTION

This Gateway Docking System Specification (GDSS) document represents the implementation of the International Docking System Standard (IDSS) Interface Definition Document (IDD) for the Gateway program. It establishes a common docking interface to support the assembly and operation of Gateway, ensuring successful integration of Gateway elements and visiting vehicles.

This document details the physical geometric mating interface and design loads requirements for Gateway docking system. The physical geometric interface requirements must be strictly followed to ensure spacecraft and element mating compatibility. This includes both defined components and areas that are void of components. The document also identifies common design parameters as defined in the IDSS IDD section 3.0, e.g., docking initial conditions and mass properties.

1.1 PURPOSE AND SCOPE

The purpose of this GDSS document is to define the interface characteristics and performance capability of the Gateway docking system and provide basic common design parameters of Gateway docking system interface to allow developers to independently design compatible docking systems. This GDSS is intended to govern the development of all docking systems used on Gateway, including visiting vehicles and Gateway elements.

1.2 RESNSIBILITY AND CHANGE AUTHORITY

Proposed changes to this document shall be submitted via a Change Request (CR) to the appropriate Gateway Board for consideration and disposition.

All such requests will adhere to the DSG Configuration Management Change Process documented in DSG-PLAN-004.

2.0 DOCUMENTS

2.1 APPLICABLE DOCUMENTS

The following documents include specifications, models, standards, guidelines, handbooks, and other special publications. The documents listed in this paragraph are applicable to the extent specified herein.

Document Number Document Revision

Document Title

SSQ 22680 Current Revision

Connectors, Rectangular, (ORU), Space Quality, General Specification For

IDSS IDD Revision E International Docking System Standard (IDSS) Interface Definition Document (IDD)

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Document Number Document Revision

Document Title

IDSSIDD-DCN-041 Revision A IDSS IDD Mechanical Capture Latch Striker Rigging Updates

2.2 REFERENCE DOCUMENTS

The following documents contain supplemental information to guide the user in the application of this document.

Document Number

Document Revision

Document Title

DSG-SPEC-GNC-

Draft Gateway Program Subsystem Specification for Guidance, navigation, and Control (GNC)

SSP 51075 NASA Docking System (NDS) Block 2 (NDSB2) Interface Definition Document (IDD)

2.3 ORDER OF PRECEDENCE

The IDSS IDD Revision E plus IDSS-DCN041A is the parent document of this GDSS. In the event of a conflict between the text of this document and any other documents, the GDSS document takes precedence.

3.0 GATEWAY DOCKING SYSTEM SPECIFICATION

3.1 GENERAL

The following subsections describe the system interfaces for the GDSS.

3.1.1.1 SYSTEM DESCRIPTION

3.1.1.2 DOCKING

The GDSS presumes a pre-docking rendezvous phase along with a 2-stage approach to docking. The rendezvous stage involves an active, chaser docking vehicle navigating to the passive, target docking vehicle to align their docking interfaces for the docking stage. The passive vehicle provides targets to assist the active vehicle in performing the precise alignment needed to mesh the mechanical interfaces at the start of the docking stage. Targets are available to the active vehicle for alignment to within the capture envelope specified by the docking system’s Initial Contact Condition requirements. This completes the rendezvous stage.

The first stage of docking establishes the initial capture of the docking vehicles, and is performed by the Soft Capture System (SCS). During the capture phase, the active docking mechanism’s SCS aligns with and latches to the passive docking mechanism, then stabilizes

Release Date: JUNE 30, 2019 Page: 9 of 57 the newly joined spacecraft relative to each other. The soft capture system then pulls the docking spacecraft together in order to initiate the second stage of docking, performed by the Hard Capture System (HCS). The HCS performs structural latching and sealing at the docking interface in order to transfer structural loads between the spacecraft and to create a transfer tunnel which can be pressurized for crew and cargo transfer for joint mission operations. The docking operation needs to be completed within a maximum time to ensure a safe docking operation.

The GDSS defines a passive interface and the minimum required features of the active interface required to complete a docking event. Many of the figures referenced throughout this document depict androgynous interfaces; however, the GDSS does not preclude androgyny. Androgyny is defined in IDSS Rev E Section 3.1.1.1. The passive SCS interface consists of capture ring features, guide petals, mechanical latch strikers and potential sensors. The term “striker” refers to the area on the passive side of the mating interface which is intended to be a contact surface for an active component on the active side of the mating interface. During docking soft capture, the guide petals are the first element to make contact; this is referred to as initial contact. The active SCS then responds to correct the lateral and angular misalignment between the two opposing interfaces. Soft capture is complete when the active capture ring is in full contact with the passive capture ring features and the active mechanical capture latches are fully engaged with the mechanical latch strikers on the passive interface.

The SCS then aligns the two mating vehicles and retracts to bring the two hard capture interfaces into hard capture range. Fine alignment is accomplished by a combination of SCS retraction and HCS guide pins.

The HCS uses active hooks to engage opposing passive hooks to provide the structural connection and pressure seal compression. The GDSS defines a passive HCS which consists of a tunnel, 12 passive hooks, fine alignment guide pins and receptacles, sensors, sensor strikers, and passive resource umbilicals.

The docking operation is complete when the mechanical hooks and resource umbilicals are fully engaged.

3.1.2 ENGINEERING UNITS OF MEASURE

All dimensions are in millimeters. All angular dimensions are in degrees. Unless otherwise specified, the dimensional tolerances are as follows:

xx implies xx ± 1 mm xx.x implies xx.x ± 0.5 mm xxº implies xxº ± 30’

3.2 MATING INTERFACE DEFINITION

[L2-MECH-001] The Gateway docking interface shall conform to the definition described in the IDSS IDD Section 3.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

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3.2.1 TRANSFER PASSAGEWAY

[L2-MECH-002] The Gateway docking system transfer passageway shall be in accordance with the IDSS IDD Section 3.2.1.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.2 SOFT CAPTURE SYSTEM

[L2-MECH-003] The Gateway soft capture system (SCS) definition shall be in accordance with the IDSS IDD Section 3.2.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

NOTE: See IDSS IDD-DCN-041 Revision A for updates to section 3.2.2.4.

3.2.2.1 GUIDE PETAL SYSTEM

[L2-MECH-004] The Gateway docking system guide petals shall be in accordance with the IDSS IDD Section 3.2.2.1.

3.2.2.2 SOFT CAPTURE RING

The SCS ring retraction and actuation is as defined in the IDSS IDD Section 3.2.2.2.

3.2.2.3 RESERVED

3.2.2.4 MECHANICAL CAPTURE LATCH SYSTEM

[L2-MECH-005] The mechanical latches and strikers shall be in accordance with IDSS IDD DCN 041 Revision A.

Rationale: To implement the common interfaces as defined in the IDSS IDD. This section is updated in accordance with IDSS IDD DCN 041 Revision A.

3.2.2.4.1 MECHANICAL CAPTURE LATCH STRIKER DIMENSIONS

DESCRIPTION

[L2-MECH-006] The mechanical capture latch striker dimensions description shall be in accordance with IDSS IDD DCN 041 Revision A.

Rationale: To implement the common interfaces as defined in the IDSS IDD. This sub-section is added in accordance with IDSSIDD-DCN-041 Revision A.

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3.2.2.4.1.1 INTERPRETATION OF PARAMETERS

[L2-MECH-007] The mechanical capture latch striker key parameters shall be in accordance with IDSS IDD DCN 041 Revision A.

Rationale: To implement the common interfaces as defined in the IDSS IDD. This sub-section is added in accordance with IDSSIDD-DCN-041 Revision A.

3.2.2.5 SOFT CAPTURE SENSOR ACTUATION

[L2-MECH-08] The soft capture sensor actuation shall be in accordance with the IDSS IDD Section 3.2.2.5.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.2.6 SOFT CAPTURE SENSOR STRIKERS

[L2-MECH-009] The soft capture sensor strikers shall be in accordance with the IDSS IDD Section 3.2.2.6.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.3 HARD CAPTURE SYSTEM

[L2-MECH-010] The Hard Capture System (HCS) shall be in accordance with the IDSS IDD Section 3.2.3.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.3.1 TUNNEL

The HCS tunnel is as defined in the IDSS IDD Section 3.2.3.1.

3.2.3.2 SEALING SURFACE

[L2-MECH-011] The HCS shall provide a sealing surface per Figure 3.2.3.2-1. The pressure seals are located internally with respect to the tangential hook location.

Rationale: The GDSS passive docking system provides a sealing surface for the active docking system pressure seals.

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(This figure to be re-created for GDSS)

FIGURE 3.2.3.2-1 HCS SEALING SURFACE

3.2.3.3 GUIDE PINS AND RECEPTACLES

[L2-MECH-012] The HCS guide pins and receptacles shall be in accordance with the IDSS IDD Section 3.2.3.3.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.3.4 HARD CAPTURE HOOKS

[L2-MECH-013] The HCS hooks shall be in accordance with the IDSS IDD Section 3.2.3.4, except Figure 3.2.3.4-4 HCS Active Hook and Figure 3.2.3.4-9 Load Response of Passive Hook Mechanism (Including Spring Washer Stack).

3.2.3.4.1 LOAD RESPONSE OF PASSIVE HOOK MECHANISM

[L2-MECH-014] The load response (stiffness) of the Passive Hard Capture Hook Mechanism shall be between the upper and lower curves as defined in Figure 3.2.3.4.1-1, Load Response of Passive Hook Mechanism (including Spring Washer Stack).

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Rationale: A passive docking interface will not require active hooks. The active hook definition is provided for reference. The revised Load Response of the Passive Hook Mechanism expands the allowable IDSS IDD stiffness range for the passive hook assembly.

FIGURE 3.2.3.4.1-1 LOAD RESPONSE OF PASSIVE HOOK MECHANISM (INCLUDING

SPRING WASHER STACK)

3.2.3.5 HARD CAPTURE STRIKER AREAS

[L2-MECH-015] The HCS striker zones shall be in accordance with the IDSS IDD Section 3.2.3.5.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.3.6 SEPARATION SYSTEM – GENERAL

The Gateway passive docking system is compatible with the active separation system force and energy limits defined below.

3.2.3.6.1 SEPARATION SYSTEM – FORCE LIMITS

[L2-MECH-016] The separation system force shall be in accordance with the IDSS IDD Section 3.2.3.6.1.

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3.2.3.6.2 SEPARATION SYSTEM – ENERGY

[L2-MECH-017] The separation system total energy shall be in accordance with the IDSS IDD Section 3.2.3.6.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.3.7 HCS COMPRESSIVE FORCE RESISTANCE DURING SCS RETRACTION

[L2-MECH-018] The total HCS resistance force shall be in accordance with the IDSS IDD Section 3.2.3.7.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.2.4 ELECTRICAL BONDING

GDSS compliant systems establish Class H, Class R, and Class S bond paths across the GDSS interfaces that are in accordance with the requirements of NASA-STD-4003A to mitigate electrical hazards on the integrated subsystem interfaces.

3.2.4.1 SOFT CAPTURE SYSTEM

[L2-MECH-019] Initial contact between GDSS mechanisms shall be through <TBD 3-1> kilohms to mitigate damage and EMI effects due to high voltage differentials between vehicles/elements at docking.

Rationale: GDSS compliant mechanisms protect against electrostatic discharge through the soft capture system. The bond path may be through any metal to metal contact provisions for this purpose. The requirement is from initial contact to hard capture during the docking operation.

3.2.4.1.1 VOLTAGE DIFFERENTIALS

[L2-MECH-020] The voltage differentials between vehicles shall be less than 80 V prior to hard dock contact to prevent damages and contamination to IDSS compliant mechanisms.

Rationale: Limiting the voltage differentials between vehicles is necessary to prevent damage and contamination to GDSS compliant mechanisms.

3.2.4.2 HARD CAPTURE SYSTEM

[L2-MECH-021] GDSS compliant mechanisms are to provide a low impedance path to protect against RF emissions, as well as minimize noise voltages and maintain outer mold line shielding effectiveness. The bond path is through metal to metal contact on the seal interface between two GDSS compliant HCS mechanisms.

The HCS, after latching, shall comply with the -025 bond requirement of NASA-STD-4003A.

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In order to prevent electrical shock and other hazards associated with the electrical faults, the GDS must provide a fault current return path across the interface. The HCS, after latching, shall comply with the Class H bond requirement of NASA-STD-4003A.

Rationale: Various bonding classifications serve different purposes. For example, at soft capture, the docking system would need a class S bond, but at hard capture, or at least after umbilical mating, the docking system would need a class R and class H bond across the interface. Class R, although it has a lower resistance than class H, is not a substitute for class H; class H must be able to carry fault currents whereas a class R is only required to carry low amplitude noise currents. A single bond path may satisfy all three bond classes simultaneously.

3.2.5 ACTIVE DOCKING SYSTEM INTERFACE COMPATIBILITY

[L2-MECH-022] The active docking system shall mate with the passive docking system defined in sections 3.2.2 and 3.2.3.

Rationale: Thermal and vacuum environment requirements described in the IDSS IDD section 3.2.5 are defined in <TBD 3-2> Environments Specification for Gateway.

The GDSS provides a detailed definition of passive docking system interfaces but does not completely control active docking system geometry. Since Gateway active docking systems are less constrained by the GDSS, active docking system providers must show compatibility with the passive docking system features defined in sections 3.2.2 and 3.2.3. Active docking system features are defined in several GDSS figures for reference and to ensure the GDSS passive docking system definition does not preclude androgyny.

3.2.6 RESERVED

Reserved.

3.3 DOCKING PERFORMACE

The GDS performance description is as defined in the IDSS IDD Section 3.3.

3.3.1 SOFT CAPTURE SYSTEM

The GDS SCS performance is as defined in the IDSS IDD Section 3.3.1.

3.3.1.1 COORDINATE SYSTEMS

The coordinate systems are as defined in the IDSS IDD Section 3.3.1.1.

3.3.1.2 RESERVED

Reserved.

3.3.1.3 RESERVED

Reserved.

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3.3.1.4 LOADS

[L2-MECH-023] Any passive GDSS compliant mechanism shall meet both functional and performance requirements after exposure to the active docking system loads defined in the IDSS IDD Rev E, Table 3.3.1.4-1 and Table 3.3.1.4-2.

Rationale: Tables 3.3.1.4-1 and 3.3.1.4-2 of the IDSS IDD define the loads that passive GDSS compliant mechanisms may encounter from active docking systems. The passive mechanisms must maintain functionality after exposure to these loads. Clarified this IDSS IDD requirement to align with the passive-centric GDSS approach.

3.3.2 HARD CAPTURE SYSTEM

3.3.2.1 MATED LOADS

[L2-MECH-024] The HCS interface mated loads shall certify to the loads shown in Table 3.3.2.1-1 and Table 3.3.2.1-2.

Rationale: HCS interfaces must certify to these loads to ensure that they can withstand anticipated Gateway HCS mated load sets.

TABLE 3.3.2.1-1 HCS MAXIMUM MATED LOADS

Load Set Mated Gateway Trans-Lunar

Maximum Design Pressure 1 048 hPa 0 hPa

Seal Closure Force 97 150 N 97 150 N

Compressive Axial Load 17 700 N 28 725 N

Tensile Axial Load 17 700 N 28 725 N

Shear Load 16 700 N 4 605 N

Torsion Moment 65 215 Nm 15 000 Nm

Bending Moment 68 700 Nm 22 846 Nm

TABLE 3.3.2.1-2 HCS MATED LOAD SETS

Load Set Case 1 Case 2 Case 3 Case 4 Case 5

Design Pressure 1 048 hPa 1 048 hPa 1 048 hPa 1 048 hPa 1 048 hPa

Seal Closure Force 97 150 N 97 150 N 97 150 N 97 150 N 97 150 N

Compressive Axial 17 700 N 13 700 N 934 N 28 725 N 4 985 N

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Tensile Axial Load 17 700 N 13 700 N 934 N 28 725 N 4 985 N

Shear Load 14 800 N 16 700 N 2 935 N 4 605 N 4 985 N

Torsion Moment 15 000 Nm 15 000 Nm 1 315 Nm 15 000 Nm 65 215 Nm

Bending Moment 39 200 Nm 68 700 Nm 12 046 Nm 22 846 Nm 39 185 Nm

Notes: (for Table 3.3.2.1-1 and Table 3.3.2.1-2)

a) Values are design limit loads.

b) Hard capture hook preload and tunnel stiffness will be such that, when under external loading within limits, there remains metal-to-metal contact in the local vicinity of the hooks.

c) Shear loads may be applied in any direction in the HCS mating plane.

d) Bending moment may be applied about any axis in the HCS mating plane.

e) The outer seal bead is to be used for all pressure calculations.

f) Load cases are defined in Table 3.3.2.1-1 and Table 3.3.2.1-2 is a summary of the maximum loads.

g) Case descriptions:

Case 1 - Interface loads due to ISS segment berthing.

Case 2 - Orbiter-sized vehicle translation with payload attached to ODS.

Case 3 - Applicable loads during a docking sequence after 1 gang of 6 hooks is closed and prior to 12 hooks closed.

Case 4 - Unpressurized high axial tension load case; modified from Orion/Gateway Element lunar orbit insertion burn analysis.

Case 5 - High torsion/low shear case for Gateway mated operations.

3.4 RESOURCE TRANSFER UMBILICALS

The GDSS resource umbilical connector interfaces transfer electrical power, data and fluid resources between two docked vehicles. There are two electrical umbilical connectors for low power/data transfer with two additional electrical umbilical connectors for high power only.

For the fluid resources transfer, there are four umbilical couplings for coolant and propellant fluids.

[L2-MECH-025] Umbilical hardware shall comply with the Keep Out Zones (KOZ) as defined in Figure 3.4-1, Umbilical Connector Keep-Out-Zones.

Rationale: All umbilical connectors have been mechanized such that they are recessed below the docking mating plane during docking, and then are driven to mate after docking hard capture occurs. During undocking, the connectors are nominally deactivated and driven to the unmated state prior to unlatching the hooks.

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FIGURE 3.4-1 UMBILICAL CONNECTOR KEEP-OUT ZONES

3.4.1 RECTANGULAR UMBILICAL CONNECTORS

There are two types of electrical umbilical connectors that Gateway element connections use.

The Visiting Vehicle (VV) Rectangular Umbilical Connector (RUC) that transfers low power and data, and the Gateway High Power (HP) RUC that transfers high power between Gateway modules. See Figure 3.4.1-1, VV RUC and Figure 3.4.1-2, HP RUC. When using the term RUC alone, it applies to both connectors.

The RUC function is nominally accomplished using two connector systems for redundancy, and arranged to allow for androgynous operation.

Figure Requires Update

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FIGURE 3.4.1-1 VV RUC

FIGURE 3.4.1-2 HP RUC

3.4.1.1 RUC PART NUMBERS

[L2-MECH-026] GDSS compliant systems shall use connectors that are, as a minimum, compatible with the interface dimensions and interface performance of the part numbers listed in Table 3.4.1.1-1 RUC Part Number.

Rationale: RUCs are to be designed, manufactured, and tested to meet SSQ 22680, Connectors, Rectangular, (ORU), Space Quality, General Specification For. The RUC part numbers which correspond to this connector definition are shown in Table 3.4.1.1-1, RUC Part Number.

Figure Requires Update

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TABLE 3.4.1.1-1 RUC PART NUMBER

PART NUMBER Power DESCRIPTION

SSQ 22680-021 Low Plug (Pins), Connector Using Insert Arrangement K

SSQ 22680-022 Low Receptacle (Sockets), Connector Using Insert Arrangement K

SSQ 22680-001 High Plug (pins), Connector Using Insert Arrangement A

SSQ 22680-002 High Receptacle (Sockets), Connector Using Insert Arrangement A

3.4.1.2 RUC OPERATION

[L2-MECH-027] The plug RUC and receptacle RUC (across the docking interface) shall be designed to mate to and demate from the opposing plug RUC and receptacle RUC as represented in Figure 3.4.1.2-1, RUC Electro-Mechanical Actuator Concept of Operation.

Rationale: During docking operations, either a plug RUC Electro-Mechanical Actuator (EMA) or a receptacle RUC EMA is driven to mate the Electrical Resource Connector. This ensures the plug RUC and receptacle RUC achieve proper connection during docking activities. Note: Removed reference to data bus switches as stated in IDSS IDD. There are no data bus switches on the RUC since there is no MIL-STD-1553 data.

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FIGURE 3.4.1.2-1 RUC ELECTRO-MECHANICAL ACTUATOR CONCEPT OF OPERATION

3.4.1.3 CONNECTOR LOCAL COORDINATE SYSTEM

VV RUC and HP RUC local coordinate system is as defined in IDSS IDD section 3.4.1.3.

3.4.1.4 LOCATING REQUIREMENTS

3.4.1.4.1 LATERAL MOUNTING REQUIREMENTS

[L2-MECH-028] Docking systems which implement the RUC function shall locate two RUCs, one receptacle and one plug, as shown in Figure 3.4.1.4.1-1, Electrical Transfer Umbilical Connectors, and two HP RUCs, one receptacle and one plug, as shown in Figure in Figure 3.4.1.4.1-1.

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Rationale: The location of the RUC components is specified to ensure proper mating during docking activities.

* Connector positional tolerances with respect to Line of Symmetry or Line of Androgyny.

FIGURE 3.4.1.4.1-1 ELECTRICAL TRANSFER UMBILICAL CONNECTORS

3.4.1.4.2 ROTATIONAL MOUNTING REQUIREMENTS

[L2-MECH-029] The Plug and Receptacle RUCs shall be in accordance with IDSS IDD section 3.4.1.4.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.4.3 CENTERLINE ANGULAR MOUNTING REQUIREMENTS

[L2-MECH-030] The Plug and Receptacle RUCs shall be mounted in accordance with IDSS IDD section 3.4.1.4.3.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.4.4 ENGAGEMENT MECHANISM

The RUC system mechanism translates the connector to engage with the opposing side as shown in Figure 3.4.1.4.4-1, RUC Mating Operation with Active Plug, and Figure 3.4.1.4.4-2, RUC Mating Operation with Active Receptacle.

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* Mechanism end of travel requirement with no mating connector present.

** Final position for engaged receptacle including axial compliance.

FIGURE 3.4.1.4.4-1 RUC MATING OPERATION WITH ACTIVE PLUG

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* Mechanism end of travel requirement with no mating connector present.

** Final position for engaged receptacle including axial compliance.

FIGURE 3.4.1.4.4-2 RUC MATING OPERATION WITH ACTIVE RECEPTACLE

3.4.1.4.4.1 RETRACTION POSITION

[L2-MECH-031] The mechanism shall locate the active and passive connectors in the retracted position as shown in Figure 3.4.1.4.4-1 and Figure 3.4.1.4.4-2 prior to commencing docking or undocking operations.

Rationale: To implement the common interfaces as defined in the IDSS IDD. The GDSS does not point to the IDSS IDD for this requirement because referenced figures have been revised to remove the MIL-STD-1553 data bus switch references.

3.4.1.4.4.2 EXTENDED POSITION

[L2-MECH-032] The mechanism shall provide sufficient stroke to meet the extended position as shown in Figure 3.4.1.4.4-1 and Figure 3.4.1.4.4-2 after structural connection is achieved.

Rationale: To implement the common interfaces as defined in the IDSS IDD. The GDSS does not point to the IDSS IDD for this requirement because referenced figures have been revised to remove the MIL-STD-1553 data bus switch references.

3.4.1.5 COMPENSATION OF MISALIGNMENT

RUC compensation of misalignment is as defined in IDSS IDD section 3.4.1.5.

3.4.1.5.1 PLANAR MISALIGNMENT COMPLIANCE

[L2-MECH-033] The Plug RUC planar misalignment compliance shall be in accordance with IDSS IDD section 3.4.1.5.1.

Rationale: To implement the common interfaces as defined in the IDSS IDD

3.4.1.5.1.1 LATERAL MISALIGNMENT COMPLIANCE

[L2-MECH-034] The planar misalignment mechanism shall provide a minimum lateral misalignment compliance in both the X and Y directions when subject to zero rotational misalignment as specified in Figure 3.4.1.5.1.1-1, Plug RUC Lateral Compliance in X Direction, and Figure 3.4.1.5.1.1-2, Plug RUC Lateral Compliance in Y Direction.

Rationale: A planar misalignment mechanism that provides the defined minimum lateral misalignment compliance in the X and Y directions ensures that RUC components can tolerate the defined misalignment and effectively mate.

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FIGURE 3.4.1.5.1.1-1 PLUG RUC LATERAL COMPLIANCE IN X DIRECTION

FIGURE 3.4.1.5.1.1-2 PLUG RUC LATERAL COMPLIANCE IN Y DIRECTION

3.4.1.5.1.2 ROTATIONAL MISALIGNMENT COMPLIANCE

[L2-MECH-035] The planar misalignment mechanism shall provide a minimum rotational misalignment compliance when subject to zero lateral misalignment as defined in Figure 3.4.1.5.1.2-1, Plug RUC Rotational Compliance about the Z axis.

Rationale: A planar misalignment mechanism that provides the defined minimum rotational misalignment compliance ensures that RUC components can tolerate the defined misalignment and effectively mate.

Figure Requires Update

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FIGURE 3.4.1.5.1.2-1 PLUG RUC ROTATIONAL COMPLIANCE ABOUT THE Z AXIS

3.4.1.5.1.3 RE-CENTER CAPABILITY

3.4.1.5.1.3.1 RE-CENTERING LATERAL POSITION

[L2-MECH-036] The planar misalignment mechanism shall return the RUC to its neutral position within the positional tolerance shown in Figure 3.4.1.4.1-1.

Rationale: This functionality will ensure that RUC components return to the neutral position after demating, reducing the potential misalignment between RUC components during future mating activities.

3.4.1.5.1.3.2 RE-CENTER ROTATIONAL POSITION

[L2-MECH-037] The RUC re-center rotational position shall be in accordance with IDSS IDD section 3.4.1.5.1.3.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.5.1.3.3 RE-CENTERING FORCE

[L2-MECH-038] The lateral re-centering force shall be in accordance with IDSS IDD section 3.4.1.5.1.3.3.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.5.2 AXIAL MISALIGNMENT COMPLIANCE

[L2-MECH-039] The Receptacle RUC axial misalignment compliance shall be in accordance with IDSS IDD section 3.4.1.5.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

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3.4.1.5.2.1 AXIAL COMPLIANCE

[L2-MECH-040] The axial misalignment mechanism shall provide axial compliance as shown in Figure 3.4.1.5.2.1-1, Receptacle Axial Compliance.

Rationale: Utilizing an axial misalignment mechanism will ensure the proper connector engagement per SSQ 22680 Figure 2g (and shown as reference in Figure 3.4.1.4.4-1 and Figure 3.4.1.4.4-2).

FIGURE 3.4.1.5.2.1-1 RECEPTACLE RUC AXIAL COMPLIANCE

3.4.1.5.2.2 MINIMUM RESISTIVE FORCE

[L2-MECH-041] The RUC minimum resistive force shall be in accordance with IDSS IDD section 3.4.1.5.2.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.5.2.3 MAXIMUM CONNECTOR INSERTION FORCE

[L2-MECH-042] The RUC maximum insertion force shall be in accordance with IDSS IDD section 3.4.1.5.2.3.

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3.4.1.5.2.4 ANGULAR COMPLIANCE

[L2-MECH-043] The RUC angular compliance shall be in accordance with IDSS IDD section 3.4.1.5.2.4.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.5.3 MISALIGNMENT KEEP OUT ZONE

[L2-MECH-044] Any hardware location or mechanism behavior designed to satisfy misalignment compensation requirements shall not exceed the KOZ shown in Figure 3.4-1.

Rationale: Hardware designed to satisfy misalignment compensation requirements must be located in such a way that the hardware does not exceed the KOZ in any alignment within defined limits.

3.4.1.6 STRUCTURAL REQUIREMENTS

3.4.1.6.1 STRUCTURAL STIFFNESS REQUIREMENT

[L2-MECH-045] The RUC structural stiffness shall be in accordance with IDSS IDD section 3.4.1.6.1.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.6.2 STRUCTURAL LOAD REQUIREMENT

[L2-MECH-046] The RUC structural load shall be in accordance with IDSS IDD section 3.4.1.6.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.7 RESERVED

Reserved.

3.4.1.7.1 RESERVED

Reserved.

3.4.1.7.2 RESERVED

Reserved.

3.4.1.7.3 RESERVED

Reserved.

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3.4.1.8 RUC SHELL CONFIGURATION

The RUC shell configuration is as defined in IDSS IDD section 3.4.1.8.

3.4.1.8.1 RUC RECEPTACLE SHELL DIMENSIONS

[L2-MECH-047] The RUC receptacle docking interface shall be in accordance with IDSS IDD section 3.4.1.8.1.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.8.2 RUC PLUG SHELL DIMENSIONS

[L2-MECH-048] The RUC plug docking interface shall be in accordance with IDSS IDD section 3.4.1.8.2.

Rationale: To implement the common interfaces as defined in the IDSS IDD.

3.4.1.9 POWER/DATA UMBILICAL CONNECTOR PIN CONFIGURATION

The Gateway Docking System has two umbilical connectors for power and data external to the pressure seals at the Visiting Vehicle (VV) to the passive GDS interface. These umbilical connectors are called Visiting Vehicle (VV) RUC. There are two additional umbilical connectors for high power transfer that are called the High Power (HP) RUC.

Each VV RUC is a SSQ 22680 connector that contains both power and data in the same connector shell. The HP RUCs are also SSQ 22680 connectors and carry only power in the connector shell.

[L2-MECH-049] The GDSS VV RUCs shall utilize the connector pinout assignments, as designated in Table 3.4.1.9-1A, GDSS VV RUC Pinouts,, and in Figure 3.4.1.9-1A, VV RUC Receptacle (Sockets) – Front Face, and Figure 3.4.1.9-2A, VV RUC Plug (Pins) – Front Face.

[L2-MECH-050] The GDSS HP RUCs shall utilize the connector pinout assignments, as designated in Table 3.4.1.9-1B, GDSS HP RUC Pinouts, and in Figure 3.4.1.9-1B, HP RUC Receptacle (Sockets) – Front Face, and Figure 3.4.1.9-2B, HP RUC Plug (Pins) – Front Face.

All pins and receptacles identified in Table 3.4.1.9-1 shall be installed.

[L2-MECH-050.1] All pins and receptacles identified in Tables 3.4.1.9-1A, 3.4.1.9-1B, 3.4.1.9- 3A, and 3.4.1.9-3B shall be installed.

Rationale: This section defines all the low power and data connector pinouts including unassigned pins, and it defines the high power connector pinouts including unassigned pins.

Active docking system designers may choose to not install individual pins and their receptacles that are not assigned. Individual pins which are not assigned may be utilized for other mission-specific purposes mutually agreed to by the docking spacecraft partners, while verifying that the signals do not cause issues (for example, electromagnetic interference, thermal, etc.) with the

Release Date: JUNE 30, 2019 Page: 30 of 57 standard GDSS functionality, and are shown in Table 3.4.1.9-3A, Unassigned GDSS VV RUC Pinouts, and Table 3.4.1.9-3B, Unassigned GDSS HP RUC Pinouts.

NOTE: Specific functions must be coordinated and documented between the two vehicles (e.g., available power and energy supplied from and to each vehicle, electrical loads, EMI suppression, etc.).

TABLE 3.4.1.9-1A GDSS VV RUC PINOUTS (2 PAGES)

Plug Umbilical Power+Data Receptacle Umbilical Power+Data

PIN # Size SIGNAL PIN # Size SIGNAL

V

To Be Supplied

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TABLE 3.4.1.9-1A GDSS VV RUC PINOUTS (2 PAGES)

Notes:

1) System A will be crossed to System B when identically configured vehicles are mated.

2) Cable shields are intended to be grounded to backshell.

TABLE 3.4.1.9-2A GDSS VV RUC PINOUTS DEFINITIONS (2 PAGES)

PIN # DEFINITION

TABLE 3.4.1.9-3A UNASSIGNED GDSS VV RUC PINOUTS

Size Pin Numbers

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FRONT FACE OF RECEPTACLE INSERT SHOWN, PLUG OPPOSITE

FIGURE 3.4.1.9-1A VV RUC RECEPTACLE (SOCKETS) - FRONT FACE

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FRONT FACE OF PLUG INSERT SHOWN, RECEPTACLE OPPOSITE

FIGURE 3.4.1.9-2A VV RUC PLUG (PINS) - FRONT FACE

TABLE 3.4.1.9-1B GDSS HP RUC PINOUTS (2 PAGES)

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TABLE 3.4.1.9-1B GDSS HP RUC PINOUTS (2 PAGES)

Notes:

1) System A will be crossed to System B when identically configured vehicles are mated.

2) Cable shields are intended to be grounded to backshell.

TABLE 3.4.1.9-2B GDSS HP RUC PINOUTS DEFINITIONS (2 PAGES)

PIN # DEFINITION

TABLE 3.4.1.9-3B UNASSIGNED GDSS HP RUC PINOUTS

Size Pin Numbers

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FRONT FACE OF RECEPTACLE INSERT SHOWN, PLUG OPPOSITE

FIGURE 3.4.1.9-1B HP RUC RECEPTACLE (SOCKETS) - FRONT FACE

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FRONT FACE OF PLUG INSERT SHOWN, RECEPTACLE OPPOSITE

FIGURE 3.4.1.9-2B HP RUC PLUG (PINS) - FRONT FACE

3.4.1.9.1 POWER TRANSFER PINS

After hard-mate is complete, the VV RUC will transfer 25 amps and 16 amps at a maximum of 136 VDC power across the docking interface. The HP RUC, after hard-mate is complete, will transfer 165 amps at a maximum of 136 VDC power across the docking interface.

3.4.1.9.2 DATA TRANSFER PINS

Data umbilical interfaces provides utilities to transfer data using 50 ohm coax cables and four data link segments of IEEE 802.3 1000Base-T Ethernet data between the mated vehicles when the host vehicle is hard mated with the visiting vehicle.

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The coaxial cables performance characteristics will meet, or exceed, the performance of characteristics specified in MIL-DTL-17/152 for coaxial cable.

3.4.1.9.3 RUC CONNECTOR MATED INDICATION

Reserved.

3.4.2 FLUID TRANSFER CONENCTORS

Fluid Transfer Connectors (FTC) transfer fluid across Gateway modules. Each FTC is self-sealing fluid coupling which provides for fluid transfer while connected. The passive FTCs are mounted rigidly and the active FTCs will provide misalignment compensation

There are four FTCs for Coolant and Propellant transfer for the passive GDS as shown in Figure 3.4-1, Fluid Transfer Connectors.

All umbilical connectors are mechanized such that they are recessed below the docking mating plane during docking, and then are driven to mate after docking hard capture occurs. During undocking, the connectors are nominally deactivated and driven to the unmated state prior to unlatching the hooks. L2-MECH

3.4.2.1 FTC PART NUMBERS

[L2-MECH-052] GDSS compliant systems shall use FTCs that are, as a minimum, compatible with the interface dimensions and interface performance of the part numbers identified in Table 3.4.2.1-1, FTC Part Number.

Rationale: Utilizing common FTC hardware will ensure that fluid transfer lines will properly mate across docking systems.

TABLE 3.4.2.1-1 FTC PART NUMBER

PART NUMBER Fluid DESCRIPTION

AXXXX Coolant Glycol

BXXXX Propellant Xenon

CXXXX Propellant Hydrazine

3.4.2.2 FTC OPERATION

[L2-MECH-053] The plug FTC and receptacle FTC (across the docking interface) shall be designed to mate to and demate from the opposing plug FTC and receptacle FTC as represented in Figure 3.4.2.2-1, FTC Electro-Mechanical Actuator Concept of Operation.

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Rationale: During docking operations, only the plug FTC Electro-Mechanical Actuator (EMA), which is mounted to and controlled by the active vehicle docking system, is driven to mate the receptacle FTC.

NOTE: The FTCs are designed as active/passive pairs, as defined in their individual specifications. This document only defines the passive mounting parameters, and the active vehicle designer should mount the active mating half for each coupling as is necessary to meet the requirements of the respective coupling specification.

FIGURE 3.4.2.2-1 FTC ELECTRO-MECHANICAL ACTUATOR CONCEPT OF OPERATION

3.4.2.3 FTC LOCAL COORDINATE SYSTEM

Reserved.

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3.4.2.4 LOCATING REQUIREMENTS

3.4.2.4.1 LATERAL MOUNTING REQUIREMENTS

[L2-MECH-054] Docking systems which implement the FTC function shall locate the FTCs as shown in Figure 3.4.2.4.1-1, Fluid Transfer Umbilical Connectors – Passive Side.

Rationale: Defining the location of the FTC hardware ensures alignment to enable successful mating after vehicle docking is complete.

* Connector positional tolerances with respect to Line of Symmetry or Line of Androgyny.

FIGURE 3.4.2.4.1-1 FLUID TRANSFER UMBILICAL CONNECTORS – PASSIVE SIDE

3.4.2.4.2 ROTATIONAL MOUNTING REQUIREMENTS

[L2-MECH-055] The Plug and Receptacle FTCs shall have a planar rotational tolerance of ±1° about the Z-axis.

Rationale: Restricting the planar rotational tolerance of the Plug and Receptacle FTCs ensures proper alignment of components for mating.

3.4.2.4.3 CENTERLINE ANGULAR MOUNTING REQUIREMENTS

[L2-MECH-056] The Plug and Receptacle FTCs shall be mounted such that the FTC centerline (Z-axis) is within a conic tolerance zone. The centerline shall be within 1° about the Z-axis with

Release Date: JUNE 30, 2019 Page: 40 of 57 the apex of the cone being at the coordinate system origin as shown in Figure 3.4.2.4.3-1, Centerline Angular Mounting Requirements.

Rationale: Restricting the centerline angular rotational tolerance of the Plug and Receptacle FTCs ensures proper alignment of components for mating.

FIGURE 3.4.2.4.3-1 CENTERLINE ANGULAR MOUNTING REQUIREMENTS

3.4.2.4.4 AXIAL MOUNTING POSITION

[L2-MECH-057] The receptacle FTC shall be mounted as shown in Figure 3.4.2.4.4-1, Coolant Receptacle FTC Axial Mounting Position, and Figure 3.4.2.4.4-2, Propellant Receptacle FTC Axial Mounting Position.

Rationale: Defining the FTC axial mounting position ensures proper alignment of components for mating.

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FIGURE 3.4.2.4.4-1 COOLANT RECEPTACLE FTC AXIAL MOUNTING POSITION

FIGURE 3.4.2.4.4-2 PROPELLANT RECEPTACLE FTC AXIAL MOUNTING POSITION

Update

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3.4.2.4.4.1 RESERVED

3.4.2.4.4.2 RESERVED

3.4.2.4.5 COMPENSATION OF MISALIGNMENT

[L2-MECH-058] The active FTCs shall mate with the passive FTCs as defined in section 3.4.2.

Rationale: Unlike RUCs, the passive FTCs are rigidly mounted and misalignment compensation must be addressed by the active FTCs.

3.4.2.4.5.1 RESERVED

3.4.2.4.5.1.1 RESERVED

3.4.2.4.5.1.2 RESERVED

3.4.2.4.5.1.3 RESERVED

3.4.2.4.5.1.3.1 RESERVED

3.4.2.4.5.1.3.2 RESERVED

3.4.2.4.5.1.3.3 RESERVED

3.4.2.4.5.2 RESERVED

3.4.2.4.5.2.1 RESERVED

3.4.2.4.5.2.2 RESERVED

3.4.2.4.5.2.3 RESERVED

3.4.2.4.5.2.4 RESERVED

3.4.2.4.5.3 RESERVED

3.4.2.4.6 STRUCTURAL REQUIREMENTS

3.4.2.4.6.1 STRUCTURAL STIFFNESS REQUIREMENT

[L2-MECH-059] The connector origin shall deflect ≤ 0.13 mm <TBR 3-1> axially when subjected to the maximum insertion force of 650 N <TBR 3-2>.

Rationale: The mechanism assembly must have sufficient structural stiffness to ensure the opposing connectors can engage properly.

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3.4.2.4.6.2 STRUCTURAL LOAD REQUIREMENT

[L2-MECH-060] The mechanism assembly shall be capable of accommodating a maximum axial force of 3025 N.

Rationale: The mechanism assembly must have sufficient structural strength when subjected to the highest compression force exerted by the mating active mechanism.

3.4.2.4.6.3 FTC KEEP OUT ZONE

[L2-MECH-061] Any secondary structural mounting hardware for the FTC passive connector shall not exceed the KOZ shown in Figure 3.4-1.

Rationale: Ensuring that structural mounting hardware does not interfere with defined KOZ will prevent interference between other docking components.

3.4.2.4.7 RESERVED

3.4.2.4.8 RESERVED

3.4.2.4.9 RESERVED

3.5 NAVIGATION AND ALIGNMENT AIDS

DSG-SPEC-GNC-009, Gateway Program Subsystem Specification for Guidance, Navigation, and Control (GNC) describes the requirements for Navigation and Alignment Aids that comprise the GDSS target system

3.6 BERTHING

GDSS passive docking systems will support berthing operations by providing the minimum functionality described below.

3.6.1 CAPTURE LATCH SYSTEM ACTUATION

[L2-MECH-062] The passive docking system total pre-capture resistive force shall be ≤ 50N

<TBR 3-3>.

Rationale: Limiting the total pre-capture resistive force ensures that the GDSS passive docking systems will support berthing operations.

3.6.2 SOFT CAPTURE SYSTEM SENSING

[L2-MECH-063] The passive docking system shall provide a soft capture indication.

Rationale: A soft capture indication is necessary to support GDSS berthing operations.

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4.0 RESERVED

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APPENDIX A - ACRONYMS AND ABBREVIATIONS

AND GLOSSARY OF TERMS

A-1 ACRONYMS AND ABBREVIATIONS

CR

EMA

FTA

GDS

Change Request Electro-Mechanical Actuator Functional Tolerance Analysis Gateway Docking System

GDSS

GN&C

HCS

HP

IDD

IDSS

KOZ

mm N

RUC

SCS

TBD

TBR

VV

Gateway Docking System Specification Guidance, Navigation, and Control Hard Capture System High Power Interface Definition Document International Docking System Standard Keep Out Zone millimeters Newton Rectangular Umbilical Connector Soft Capture System To Be Determined To Be Resolved Visiting Vehicle

A-2 GLOSSARY OF TERMS

Term Description

Reserved

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APPENDIX B - OPEN WORK

B-1 TO BE DETERMINED

Table B-1 To Be Determined Items lists the specific To Be Determined (TBD) items in the document that are not yet known. The TBD is inserted as a placeholder wherever the required data is needed and is formatted in bold type within carets. The TBD item is numbered based on the section where the first occurrence of the item is located as the first digit and a consecutive number as the second digit (i.e., <TBD 4-1> is the first undetermined item assigned in Section 4 of the document). As each TBD is resolved, the updated text is inserted in each place that the TBD appears in the document and the item is removed from this table. As new TBD items are assigned, they will be added to this list in accordance with the above described numbering scheme. Original TBDs will not be renumbered.

TABLE B-1 TO BE DETERMINED ITEMS

TBD Section Description

<TBD 3-1> 3.2.4.1 Initial contact resistance between GDSS mechanisms

<TBD 3-2> 3.2.5 Environment Specification Document for Gateway

B-2 TO BE RESOLVED

Table B-2 To Be Resolved Issues lists the specific To Be Resolved (TBR) issues in the document that are not yet known. The TBR is inserted as a placeholder wherever the required data is needed and is formatted in bold type within carets. The TBR item is numbered based on the section where the first occurrence of the item is located as the first digit and a consecutive number as the second digit (i.e., <TBR 4-1> is the first undetermined item assigned in Section 4 of the document). As each TBR is resolved, the updated text is inserted in each place that the TBR appears in the document and the issue is removed from this table. As new TBR issues are assigned, they will be added to this list in accordance with the above described numbering scheme. Original TBRs will not be renumbered.

TABLE B-2 TO BE RESOLVED ISSUES

TBR Section Description

<TBR 3-1> 3.4.2.4.6.1 Structure Stiffness Requirement (Deflection)

<TBR 3-2> 3.4.2.4.6.1 Structural Stiffness Requirement (Insertion force)

<TBR 3-3> 3.6.1 Passive docking system total pre-capture resistive force

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APPENDIX C - VERIFICATION MATRIX

The Verification Matrix identifies the L2 Program verification methods that will be utilized to satisfy the L2 Program requirements.

Rqmnt

ID

Section No./ Title

Verification Method

Verification Mechanism

Verification Success Criteria

L2-

MECH-

3.2 Mating Interface Definition

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when the inspection shows that the mechanical dimensions are within the limits as defined in IDSS Rev E section 3.2.

L2-

MECH-

3.2.1 Transfer Passageway

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when the inspection shows the mechanical dimensions do not encroach on the Transfer Passageway as defined in Figure 3.1.1.1-2 in IDSS Rev E section 3.2.1

L2-

MECH-

3.2.2 Soft Capture System

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when inspection shows that the mechanical dimensions are within the limits as defined in Figure 3.2.2-1 and 3.2.2-2 in IDSS Rev E section 3.2.2.

L2-

MECH-

3.2.2.1 Guide Petal System

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when inspection shows that the mechanical dimensions are within the limits as defined in Figure 3.2.2.1-1, 3.2.2.1-2, 3.2.2.1-3, 3.2.2.1-4 and 3.2.2.1-5 in IDSS Rev E section 3.2.2.1.

L2-

MECH-

3.2.2.4 Mechanical Capture Latch System

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when inspection shows that the mechanical dimensions are within the limits as defined in IDSS IDD DCN-041 Revision A.

L2-

MECH-

3.2.2.4.1 Mechanical Capture Latch Striker

Inspection The inspection shall use data from the design documentation (flight drawings) and

Verification shall be considered successful when inspection shows that the mechanical

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Rqmnt

ID

Section No./ Title

Verification Method

Verification Mechanism

Verification Success Criteria

Dimensions Description as built mechanical dimensions.

dimensions are within the limits as defined in Figure 3.2.2.4-1 in IDSS IDD DCN 041 Revision A.

L2-

MECH-

3.2.2.4.1.1 Interpretation of Parameters

Inspection The inspection shall use data from the design documentation (flight drawings) and as built mechanical dimensions.

Verification shall be considered successful when inspection shows that the mechanical dimensions are within the limits as defined in Figure 3.2.2.4.1.1-1 and 3.2.2.4.1.1-2 in IDSS IDD DCN 041 Revision…