PTAB

IPR2019-00505

Unified Patents LLC v. American GNC Corp

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Autonomous Navigation, Guidance and Control Process and System Based on Range and Intensity Images Provider
  • Brief Description: The ’871 patent discloses an autonomous navigation, guidance, and control process for aerospace vehicles, particularly for docking maneuvers. The system uses a Laser Dynamic Range Imager (LDRI) to generate range and intensity images of a target, calculates position and attitude errors relative to a reference trajectory, and produces control commands to guide the vehicle.

3. Grounds for Unpatentability

Ground 1: Obviousness over Dabney, Tietz, and JSC - Claims 1-11 are obvious over Dabney in view of Tietz and JSC.

  • Prior Art Relied Upon: Dabney (Patent 5,109,345), Tietz (“Development of an Autonomous Video Rendezvous and Docking System,” June 1982), and JSC (Johnson Space Center Research & Technology Annual Report 1998-1999).
  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Dabney teaches a complete autonomous docking system that performs nearly all steps of challenged claim 1. Dabney’s system uses a visual tracking sensor (a camera and laser diode) to acquire a target, a processor to calculate the relative range, roll, pitch, and yaw, and a controller to generate thruster commands to null attitude errors and maneuver the vehicle onto a docking axis. This process inherently involves providing a reference position (the docking axis), generating a carrier position/attitude relative to the target, producing a position/attitude error, and generating control commands from that error.

    • To the extent Dabney did not explicitly teach providing an "expected reference position," Petitioner asserted that Tietz, which is expressly cited and relied upon by Dabney for its foundational equations, discloses this element. Tietz teaches determining a docking axis and includes a subroutine for determining a "desired chase vehicle position, attitude," which provides the claimed reference position.

    • Petitioner contended that Dabney’s system, which uses a camera, does not explicitly disclose a "Range and Intensity Images Provider" as required by the claims. However, JSC discloses a Laser Dynamic Range Imager (LDRI) for space vehicle proximity operations. JSC describes the LDRI as a "revolutionary" technology that generates real-time range and intensity images, providing instant depth perception. Petitioner argued this directly supplies the missing limitation of claim 1 and is the exact technology recited in dependent claim 2.

    • For dependent claims, Petitioner argued that Dabney’s maneuvering of the vehicle along the docking axis teaches the "trajectory" of claim 3. Dabney's use of a low-pass filter on sensor output to reduce noise meets the "smoothing" limitation of claims 5-7. Finally, Dabney's use of a differentiator on error signals to derive rates and its subsequent collection of error variables and derivatives to generate thruster commands meets the limitations of claims 8-11.

    • Motivation to Combine (for §103 grounds): A POSITA would combine Dabney and JSC by substituting Dabney's camera-based sensor with JSC’s superior LDRI. The motivation was to improve the system's precision, robustness, and reliability, particularly by reducing the number of required sensors and improving performance in various lighting conditions. Dabney itself stated that its specific tracking sensor was "not critical," inviting substitution. A POSITA would combine Dabney and Tietz because Dabney explicitly references and relies on Tietz for the mathematical basis of its system, making it natural to incorporate Tietz’s teachings on defining a desired position.

    • Expectation of Success (for §103 grounds): A POSITA would have had a high expectation of success because the combination involved substituting one known imaging sensor for another improved, known sensor in a well-understood system to achieve the predictable result of enhanced performance.

4. Key Claim Construction Positions

  • “smoothing” (claims 5-7): Petitioner argued this term should be construed to mean “filtering.” The ’871 patent describes a shaping module to "smooth the reference relative position... to avoid a sudden input change." Petitioner asserted that a POSITA would understand this is achieved by using a low-pass filter to remove high-frequency content (e.g., spikes, noise) from the signal, which is a well-known filtering technique.

5. Relief Requested

  • Petitioner requests institution of inter partes review (IPR) and cancellation of claims 1-11 of the ’871 patent as unpatentable.