Details

Last Updated: 20 January 2013 20 January 2013

Orbital Sciences Corporation

Principal software engineer for several satellites. Responsible for software system design and development; subsystem interface design; command and telemetry definitions; ground station to spacecraft interface definition; software coding standards; reliability and multi-satellite configuration issues; command & telemetry definitions; fault detection and correction software; and hardware interface drivers.

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Orbcomm

Orbcomm is Orbital Sciences global communications satellite network consisting of 28 low earth orbiting (LEO) satellites.  The system is used to send and receive two-way alphanumeric packets, similar to two-way paging or e-mail with global coverage.

My responsibilities:

• Principal software engineer on the satellite software development team.  Responsibilities included software system design, subsystem and common (cross subsystem) software development.

• System Design
  • Overall software system design
  • Developed spreadsheet database to define ground station to spacecraft and inter-subsystem command and telemetry interfaces.  Database also is used to manage data specific to individual satellites (orbit parameters, calibration parameters, etc.).
    • C include files, with command and telemetry tables, are automatically generated for both the ground station and the satellites to enforce these interfaces, help prevent human error and increase reliability.
    • Developed preliminary Access database to replace Excel spreadsheets.
  • Software coding standards.
  • Configuration management.
  • Reliability and multi-satellite configuration issues.
  • Command & telemetry definitions.

• Subsystem Development
  • Developed the satellite's gateway (ground station interface subsystem) software.

• Common Code Development (code resident on several subsystems).
  • System level and subsystem level fault detection and correction software (Health and Maintenance).
  • Digital Signal Processor (DSP) driver (dsp communications, telemetry, code loading, memory washing)
  • SCP (Serial Communications Port) bus driver for communication with 3-wire serial devices (plls, adcs, dacs, etc)
  • Table (spreadsheet) driven command handling, and utility routines.

• Satellite Specifics
  • VxWorks operating system - WindRiver's Orbcomm page
  • 68302 processor
  • C/assembly language

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APEX

APEX (Advanced Photovoltaic and Electronics Experiment) was Oribital's first satellite and an Air Force experimental satellite to test advanced electronic components in the space environment.   - JPL Mission and Spacecraft Library:APEX, Gunter's Space Page:APEX

My responsibilities:

• Lead software engineer responsible for the software system design, development and integration.

• System Design
  • Software system design
  • Ground support equipment definition
  • Command and telemetry format definitions
  • Subsystem interface definitions

• Subsystem Development
  • Spacecraft Control Module (SCM subsystem)
    • Frame Formatter
    • Command Sequencer
    • File Backhauler
  • Payload Services Module (PSM subsystem)
    • Payload Interrogators (DOS, PP, CRUX, FERRO)

• Common Code Development (code resident on both subsystems)
  • System level and subsystem level fault detection and correction software (Health and Maintenance).
  • 68302 communications drivers (HDLC, SCLC, ascii, OX.25)

• Satellite Specifics
  • OSX operating system (a custom version of the Precise MQX operating system)
  • 68302 processor
  • C and assembly language

• Acted as technical assistant to the Air Force supporting on-orbit operations.

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X-34

X-34 - An air-launched, hypersonic rocketplane being developed by Orbital for NASA's Reusable Launch Vehicle (RLV) program.
 

• Real-time simulation development
  • Simulation of LN100 inertial navigation subsystem.
  • Simulations of other X-34 subsystems.
  • DOS drivers to configure, transmit and receive messages thru multi-channel serial communication boards (digi board, 202, others).

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BATSAT / T1

Teledesic's T1 Satellite - The world's first commercial 'Ka' frequency band LEO spacecraft (previously called the Broadband Advanced Technology satellite (BATSAT)).
 

• Developed the satellite's gateway (ground station interface subsystem) software (the design is common with the Orbcomm satellite design).
• Launch press release

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Seastar

Seastar - Orbital's second PegaStar satellite, now called OrbView-2 carries the Sea Viewing Wide Field-of-View Sensor (SeaWiFS) and provides high-fidelity color images of the Earth.
 

• VRTX operating system
• Modifications and debugging of Global Positioning System (GPS) driver.
• Modifications and debugging of OX.25 (an internal messaging protocol) driver.
• Matrix math library optomization
• Compiler/floating point math library debugging (Linking, NAN problems)