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MAGE Strength

Specification • The JAS mechanical structure shall consider tooling to hold it while installing and transporting components. Features for mounting the hardware that supports the system shall be included. A static 4 G load shall be used with positive margins per this document. Mechanical Aerospace Ground Equipment (MAGE)

Mechanical Specification > Mechanical Interface Design > MAGE Strength

Margins of Safety

Specification • Margin of Safety (MS) is defined as MS = 1/R - 1, where R is the ratio of the factored applied load (or stress) to the allowable load (or stress) and shall be greater than 0. Margin of Safety Calculation The specific failure theory used to determine the allowable load...

Mechanical Specification > Design Constraints > Structural Integrity > Margins of Safety

Materials

Specification • The JAS mechanical structure shall be constructed of materials capable of performing at the specified orbit for a minimum of ten years after being stored in an inert gas environment and after exposure to clean air during testing, launch, and ascension. The use of the following materials is prohibited: Zinc,...

Mechanical Specification > Design Constraints > Materials

Memory Access Service

Specification • Error: unable to migrate element with tag="" The following diagram shows how the JAS Memory Access Service fits into the overall communication stack. The Memory Access Service provides a standard interface to applications that allows them to remotely access memory on a JAS node across a communication link. This is...

Communication Specification > Subnetwork Services > Memory Access Service

Mezzanine Connector

Specification • A very useful option for plug-in modules is the ANSI/VITA 57 standard FPGA Mezzanine Card or FMC. This standard specifies an industry standard form factor utilizing a low profile, high-speed, high-pin count connector. The FMC connector can support very high bandwidths. The FMC approach solves the problem of how to...

Electrical Specification > Electrical Interconnects > Mezzanine Connector

Molecular Contamination

Specification • For all components that will be in the vicinity of an optical payload and anywhere that contamination at the molecular level is an issue, all parts and materials must comply with ASTM E 595 for less than 1% Total Mass Loss (TML) and 0.1% CVCM. Thermal bake-out of all components...

Mechanical Specification > Design Constraints > Cleanliness > Molecular Contamination

Packet Addressing and Routing

Specification • Packets will be identified and routed in the system using the SAPID, DAPID, ST, and SST. Applications shall provide these fields to the JAS Packet Service to create the stream of packets that will be sent across the communication channel. Communication channels and addresses, such as a SpaceWire address, can...

Communication Specification > JAS Packets > JAS Packet Definition > Packet Addressing and Routing

Packet Error Control

Specification • Even though JAS network protocols offer a guaranteed delivery option, there still exists the possibility of an error being introduced into a packet while it is being created or transferred from memory to the communication channel. To provide an additional layer of error detection all JAS packets shall contain a...

Communication Specification > JAS Packets > JAS Packet Definition > Packet Error Control

Packet Sequencing

Specification • The use of the packet sequencing fields within the JAS packet is different from the definition in the CCSDS and PUS standards. The original intention of the packet sequence counter was to provide two functions. First, it was used in combination with the sequence flags to reassemble data sets that...

Communication Specification > JAS Packets > JAS Packet Definition > Packet Sequencing

Packet Service Definitions

Specification • [Placeholder: services reserved for and specific to JAS; this is a lead in to describe the services. Contact SNL if immediate support is needed with this topic. Content will be developed for JT 2.0.]

Communication Specification > JAS Packets > Packet Service Definitions

Particulate Contamination

Specification • Internal Cavities will be wiped clean with isopropyl alcohol and allowed to air dry for 30 minutes prior to close out; the structure will be covered during the drying process. The surfaces will be visibly clean. Visibly clean is defined as no contamination visible when viewed from 6-18 inches away...

Mechanical Specification > Design Constraints > Cleanliness > Particulate Contamination

Payload

Specification • JRDDP Packet Format Secondary Header (Optional) The presence of the optional secondary header is indicated by the Secondary Header Flag in the Packet Control field. If a secondary header is present, its contents and format are implementation dependent and shall be documented in a program specific document. The secondary header...

Communication Specification > SpaceWire > Protocols > JAS Reliable Data Delivery Protocol > JRDDP Packet Format > Payload

PCI Express

Specification • PCI Express, or PCIe, is another multi-lane high speed serial interconnect technology. Each lane is a full-duplex data stream comprised of two differential signaling pairs, one for transmitting and one for receiving.

Electrical Specification > Communication Data Links > PCI Express

Potential Flight Capability

Specification • Each component of the JAS mechanical structure should consider Flight capability as this will force consideration of design, flight, and test environments described in this specification. The JAS mechanical structure should be designed for the specific application intended.

Mechanical Specification > Mechanical Interface Design > Potential Flight Capability

Power Distribution Architecture

Specification • JAS will accept at least one primary input power source supplied to the system. The primary input power will connect directly to the Power Supply or PS node in a JAS arrangement. The PS node converts the primary input voltage to a lower voltage which is then sent to all...

Electrical Specification > Power Distribution Architecture

Results 51–75 of 113