PTAB

IPR2018-00207

SZ DJI Technology Co Ltd v. Drone Control LLC

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Key Events
Petition

1. Case Identification

2. Patent Overview

  • Title: Intuitive Control of a Radio-Controlled Aircraft
  • Brief Description: The ’116 patent discloses a method for controlling a radio-controlled (RC) aircraft to address the problem of non-intuitive control when the aircraft's heading is different from the user's orientation. The system transforms control commands (e.g., roll, pitch) from a first coordinate system based on the remote control's perspective into a second coordinate system based on the RC aircraft's perspective, allowing the aircraft to maneuver relative to the user's point of view regardless of its yaw orientation.

3. Grounds for Unpatentability

Ground 1: Anticipation and/or Obviousness over Thornberg - Claims 1, 3-6, 8-11, 13-15 are unpatentable under 35 U.S.C. §§ 102/103 over Thornberg.

  • Prior Art Relied Upon: Thornberg (Patent 5,552,983).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Thornberg taught every element of the challenged claims. Thornberg explicitly addressed the same problem of "non-intuitive control of a remotely operated vehicle" and disclosed the same solution: transforming control inputs from an operator's frame of reference to the vehicle's frame of reference. Thornberg's "operator mode" used a transformation angle, derived from the vehicle's heading, to convert roll and pitch commands into the vehicle's coordinate system using the same rotation matrix equations as the ’116 patent. Thornberg also disclosed selectable modes, including a "vehicle mode" where controls are direct (the ’116 patent's "second mode") and an "operator mode" where controls are transformed for intuitive use (the ’116 patent's "first mode").
    • Motivation to Combine (for §103 grounds): To the extent any minor element was not explicitly disclosed, Petitioner argued it would have been obvious to a person of ordinary skill in the art (POSITA). For example, applying Thornberg's system, taught for a generic unmanned aerial vehicle (UAV), to a helicopter was an obvious design choice.
    • Expectation of Success (for §103 grounds): A POSITA would have a high expectation of success as Thornberg provided a detailed blueprint for implementing the claimed control scheme, including the necessary components and mathematical transformations.

Ground 2: Obviousness over Thornberg and Karem - Claims 2, 7, and 12 are obvious over Thornberg in view of Karem.

  • Prior Art Relied Upon: Thornberg (Patent 5,552,983) and Karem (Patent 6,584,382).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addressed claims 2, 7, and 12, which added the limitation of controlling the RC aircraft to a "hovering state" in response to lift command data (e.g., when controls are released). Petitioner asserted that while Thornberg disclosed the foundational control system, Karem explicitly taught a rotorcraft control unit with spring-loaded sticks that, when released to their center position, command a "complete rotorcraft hover" by providing zero horizontal and vertical velocity commands.
    • Motivation to Combine (for §103 grounds): A POSITA would combine Karem's hover-on-release feature with Thornberg's intuitive control system to enhance functionality. Since Thornberg described using UAVs for tasks like surveillance and inspection that often require hovering, adding a well-known, automated hovering capability as taught by Karem would be a predictable and desirable improvement.
    • Expectation of Success (for §103 grounds): The combination was argued to be straightforward, involving incorporating conventional spring-loaded controls and associated logic, as taught by Karem, into the remote control of Thornberg's system, with a high expectation of success.

Ground 3: Obviousness over Muramatsu - Claims 1, 3-5, 8-10, 13-15 are obvious over Muramatsu alone, or optionally in view of Thornberg.

  • Prior Art Relied Upon: Muramatsu (JP Patent Publication 2001-209427) and Thornberg (Patent 5,552,983).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner presented Muramatsu as an alternative primary reference that independently taught the core invention. Muramatsu disclosed an unmanned helicopter control system that transformed steering inputs from an operator's perspective into the helicopter's perspective to achieve intuitive control. It used a magnetic sensor on the user and another on the helicopter to determine their relative orientation, then employed the same rotational matrix transformation as the ’116 patent to convert user commands.
    • Motivation to Combine (for §103 grounds): The optional combination with Thornberg was proposed to address Muramatsu's two-step transformation (user-to-earth, then earth-to-aircraft). Petitioner argued that a POSITA would have been motivated to simplify Muramatsu's two-step process into the single-step transformation taught by Thornberg to reduce computational complexity, a well-known and obvious optimization.
    • Expectation of Success (for §103 grounds): A POSITA would have a high expectation of success in implementing Muramatsu's system or modifying it in view of Thornberg, as both references involved applying standard and well-understood coordinate transformation principles.

  • Additional Grounds: Petitioner asserted additional obviousness challenges, including Ground 4 (Muramatsu and Thornberg for claims 6, 11), Ground 5 (Muramatsu, Karem, and optionally Thornberg for claim 2), and Ground 6 (Muramatsu, Thornberg, and Karem for claims 7, 12). These grounds relied on the same core prior art teachings to address limitations related to multi-mode operation and the hovering feature in the remaining claims.

4. Key Claim Construction Positions

  • "coordinate system ... from a perspective of the RC aircraft": Petitioner proposed this term means "coordinate system based on the orientation of the RC aircraft." This construction was argued to be consistent with the specification's description of roll, pitch, and yaw axes being defined relative to the aircraft's body.
  • "coordinate system from a perspective of the remote control device": Petitioner proposed this means "coordinate system based on the orientation of the remote control device." This was based on figures and descriptions showing user commands are dependent on the direction the remote control is facing.
  • "a hovering state": Petitioner proposed this means "a state with no movement beyond an acceptable level of tolerance." This construction was based on the specification's disclosure that releasing spring-loaded controls to a center position results in "horizontal flight or substantially horizontal flight within an acceptable level of tolerance."

5. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-15 of the ’116 patent as unpatentable.