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The history of SCPNT dates back to the early days of the NASA sponsored the Gravity Probe B (GP-B) Program at Stanford.  In the mid-1980’s Brad Parkinson, who led the original development of GPS when he was in the U.S. Air Force, was recruited and hired to become the Program Manager of GP-B, and also a Professor in the Aero-Astro Department. Brad brought a wealth of spacecraft development experience in with him, which exactly fit the needs of GP-B.  One problem GP-B needed to solve is how to achieve and maintain a very, very accurate orbit in flight.  In the early 1990’s Brad and the GP-B team decided to try using the new GPS constellation of navigation satellites to achieve this requirement.  Brad, and several of his Grad Students including: Penny Axelrad (1990), Clark Cohen (1992), Glenn Lightsey (1997), Sam Pullen (1996) and Hiro Uematsu (1993), worked on and solved this problem.

Professor Parkinson and his students then turned their GPS knowledge and experience into solving navigation problems for aviation. The team began experimenting with aircraft guidance using a GPS receiver and multiple antennas on a small Cessna aircraft owned by Stanford Professor David Powell. The students were able to navigate the airplane very accurately around the skies of Palo Alto.  They then experimented with using GPS to land the aircraft  automatically at the Palo Alto Airport.  About this time (~1994) the FAA became aware of this revolutionary research being performed by Brad’s team and offered to loan Stanford a Boeing 737 to test the feasibility of using satellites (i.e. GPS), augmented with pseudo-satellites on the ground called integrity beacons to navigate and land commercial airplanes. The test, performed at NASA's Crows Landing strip near Fresno, CA, proved extremely successful. You can view a short video about the development and testing of the Stanford Integrity Beacon Landing System below.

Professor Parkinson and his team of Grad Students also started performing a series of other ground-breaking research efforts, in various areas including: GPS Integrity (i.e. WADGPS), Aircraft Surveillance and Collision Avoidance (RAIM), Autonomous Navigation (UAVs), Autonomous Farm Vehicles, etc. Some of the PhDs awarded during this period included:

  • Wide Area Differential GPS (WADGPS), Changdon Kee, 1993
  • Aircraft surveillance and collision avoidance using GPS, Ran Gazit 1996
  • Carrier differential GPS as a sensor for automatic control: Development of a full state estimation and flight control system for an autonomous aircraft based on the global positioning system, Paul Montgomery 1996
  • Carrier-phase differential GPS for automatic control of land vehicles, Mike O’Conner 1996
  • Navigation integrity for aircraft precision landing using the global positioning system, Boris Pervan, 1996
  • GPS Pseudolites: Theory, Design, and Applications, Stewart Cobb 1997
  • Robust GPS Autonomous Signal Quality Monitoring, Awele Ndili, 1998
  • Precision robotic control of agricultural vehicles on realistic farm trajectories, Tom Bell 1999

Another significant event occurred during this period with the recruitment and hiring of Professor Per Enge, who joined the Stanford team in 1992. Soon thereafter the Stanford GPS Lab was formed.

View  Paper showing Stanford doctoral student leadership in GPS research: Professional Publishing Trends of Recent GPS Doctoral Students by Leo Mallette, ION Conference Presentation, 2006.

SCPNT Historical Video Clips circa 1994 - 1998

The Development & Testing of the Stanford Integrity Beacon Landing System

An 11-minute narrated video chronicling the evolution of Stanford's Integrity Beacon automated airplane landing system from GPS-based spacecraft attitude and control guidance technology developed for the Stanford/NASA landmark Gravity Probe B mission testing Albert Einstein's general theory of relativity and its extension and augmentation by a team of Stanford graduate students into a combination satellite and ground-based pseudo-satellite (integrity beacon) system that could land a Boeing 737 aircraft autonomously in inclement (restricted visibility) weather.


This video courtesy of Stanford University Archives

See also:

GPS/Integrity Beacon B-Roll Video Segments:

Video segments showing all aspects of the GPS-related technologies used in automated airplane navigation, takeoffs and landings in 1994. This video features the team of graduate students from the Stanford University GPS Lab who pioneered and developed these technologies.

This video courtesy of Stanford University Archives

See also:



CNN and San Francisco Bay Area Television Stories:

Stanford GPS Lab auto-landing tests of a United Airlines Beoing 737 aircraft by Clark Cohen and fellow graduate students.

See also:

From Einstein to Farming Video

A 4-minute video showing how Stanford Aeronautics & Asstronautics graduate students adapted and expanded GPS and related technologies for precision navigation and autonomous control of vehicles from spacecraft to airplanes to farm tractors. These developments led to the formation the Silicon Valley company, Integrinautics, Inc., later renamed Novariant, Inc.

 See Also: Early Research — Precision Farming/Agriculture

GPS Lab Tunnel in the Sky Video:

Video showing integration of three key emerging technologies:

  • Differential GPS

  • Enbedded 3-D Graphics

  • Sunlight-readable displays

Andy Barrows, Professor J. David Powell, Professor Bradford Parkinson, and Professor Per Enge, Stanford University GPS Lab, 1998.

See Also: Early Research — Tunnel in the Sky