• Senior Subsystem Engineer 1988
  • Responsible for requirements verification, validation, systems integration and customer interface for sensor and mechanical sub-assemblies.

• Unit Engineer 1979-1983
  • Was the Responsible Engineering Authority(REA) for the three Solar Drum Positioner(SDP) units(and mating gear racks - see image below) on the HS-376 commercial communications satellite:
  • 
  • My responsibilities included:
    • Design
      • Redesigned the drive shaft and pinion gear for more efficient performance, manufacture and assembly
      • Designed various test fixtures
    • Writing Specifications
      • Assembly
      • Unit Testing
      • Spacecraft integration
      • Spacecraft subsystem test
    • Configuration and Change Management
    • All interaction with:
      • Manufacturing
      • Vendors
      • Program Management
      • Spacecraft Systems Engineers
      • Engineering Analysis
        • Stress
        • Thermal
        • Power
    • Observation and approval of all assembly, test and integration procedures

Background Notes:

Since working at Hughes had a profound impact on my career and laid the foundation for Rhythmeering, I thought some background might prove useful. The HS-376 is one of the world’s most purchased satellites. It’s innovative telescoping solar drum significantly reduced the amount of room it required for launch and provided ongoing stabilization capabilities. The 376 was the first satellite to be launched from the Space Shuttle and played a pivotal role in the rapid spread of global communications during the final two decades of the 20th century. The telescoping solar drum was a new design that had never been proven in space. I’ve also posted a few of my favorite pictures of the HS-376. There is a reasonably detailed technical description of an SDP in a COMSAT Technical Review - it’s the only such description I’ve ever seen on the web. Literally just a few weeks out of undergraduate school, I was assigned to the Solar Drum Positioner project on a temporary basis due to an unforeseen manpower shortage. The engineer working on the project had given a two week notice and my assignment was to spend every minute with him learning everything I could about the design, priorities and contacts. The project was under some significant schedule pressure and someone was going to have to answer the phones and show up for meetings until an experienced replacement was found. After many, many 16 hour days and quite a few twists of fate, I ended up being that replacement.

Although a prototype and an engineering model(beta version in the world of software) had been built and tested with satisfactory results, critical production drawings were not yet finished, some long-lead time parts needed to be ordered asap while others had just been delivered with discrepancies. Moreover, the engineering model testing environment and software simulations couldn’t represent many actual operational conditions so new complications kept cropping up. The core design(stepper motors and differential drivetrain) of the SDP had been based on a flight-proven antennae positioner. However, unlike it’s ancestor which was a solitary device with a rigid coupling to its payload, the three SDP units had to work in concert with each other and were loosely coupled to the outer deployed solar drum via three gear racks(see the illustration above).

Since a half dozen of the HS-376 spacecraft had already been ordered and more proposals were in the pipeline, these challenges got the attention of upper management. This led to my being in regular meetings with very senior design engineers and high level spacecraft systems engineers whose radar screens the SDP was always popping up on. As a result, I was simultaneously learning about the kinds of detailed design and “big picture” systems engineering insights which ultimately led to the development of Rhythmeering. The overwhelmingly successful outcome of this “trial by fire” experience gave me the critical systems engineering skills and confidence to take on complex projects.

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