PTAB

IPR2025-01602

Avidbots USA Corp v. Brain Corp

Log In
Key Events
Petition

1. Case Identification

2. Patent Overview

  • Title: Systems and Methods for Constraining a Graph Representation of an Environment
  • Brief Description: The ’325 patent discloses systems and methods for an autonomous robot to generate a map of an environment. The technology involves creating a graph of nodes from sensor data, performing "scan matching" between different nodes to create extended scan groups, and constraining the graph by ensuring the robot's start and end locations are substantially similar, a process known in the art as "loop closing."

3. Grounds for Unpatentability

Ground 1: Claims 1-18 are anticipated by Olson under 35 U.S.C. §102.

  • Prior Art Relied Upon: Olson (Giorgio Olson, et al., Robust and Efficient Robotic Mapping, a Massachusetts Institute of Technology PhD thesis, June 2008).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Olson, a foundational text on robotic mapping, disclosed every element of the challenged claims. Olson described an optimization algorithm for robots to construct maps from noisy sensor data using a graph-based approach where nodes represent robot poses. The thesis explicitly detailed generating a graph from sensor scans as a robot travels, performing scan matching on groups of sensor readings (extended scan groups) to align scans and reduce error, and using "loop closing" to refine the robot's trajectory estimate. Petitioner asserted that Olson’s loop closing—which constrains the graph when a robot recognizes it has returned to its starting position—is the same as the ’325 patent’s key limitation of constraining the graph between a start and end location that are substantially similar. Olson also taught optimizing the graph based on confidence values (the inverse of a covariance matrix) and generating a final map, meeting the limitations of all dependent claims.

Ground 2: Claims 1-18 are anticipated by Stachniss under 35 U.S.C. §102.

  • Prior Art Relied Upon: Stachniss (Cyrill Stachniss, et al., "Simultaneous localization and mapping," a chapter in the Springer Handbook of Robotics, 2d ed., publicly available January 2016).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that Stachniss, a comprehensive introduction to Simultaneous Localization and Mapping (SLAM), also anticipated all challenged claims. Stachniss taught graph-based optimization techniques where robot locations and landmarks are treated as nodes in a graph. It described using visual and range data from sensors to identify loop closures and build maps. Petitioner argued that Stachniss disclosed using scan-matching techniques on overlapping sensor measurements from different poses (extended scan groups) to enable visual odometry and trajectory optimization. Furthermore, Stachniss explicitly described imposing constraints via loop closure when a robot returns to a previously visited location, which refines the uncertainty of its position estimate. This process of constraining the graph upon returning to a starting point was argued to meet the core limitation of the independent claims. Stachniss also disclosed associating a range of uncertainty (represented by shaded ellipses) with each node and optimizing the graph by solving for a state of minimal energy, which corresponds to the patent's claims related to confidence values and cost functions.

Ground 3: Claims 1-18 are obvious over Olson or Stachniss in view of Fong under 35 U.S.C. §103.

  • Prior Art Relied Upon: Olson or Stachniss, in combination with Fong (Patent 9,538,892).

  • Core Argument for this Ground:

    • Prior Art Mapping: To the extent Olson or Stachniss do not anticipate every limitation, Petitioner argued the claims would have been obvious when combining either reference with Fong. Fong disclosed an autonomous cleaning robot that uses a mapping/navigation system and "pose-defining fiducial markers" on its docking station to assist in navigation. Petitioner asserted that Fong’s fiducial markers serve as a "home locator" for its docking station, which constitutes a specific implementation of the start/end locations claimed in the ’325 patent. The combination of Olson's or Stachniss's advanced SLAM mapping system with Fong's specific robot application was argued to be obvious.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine these references to implement a known, robust mapping system (from Olson or Stachniss) on a commercially relevant platform like an autonomous cleaning robot (from Fong). Fong itself taught using "any suitable mapping and localization method, including SLAM techniques," directly inviting the integration of systems like those in Olson and Stachniss. The motivation was to improve the mapping and navigation capabilities of a known type of autonomous robot.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because applying advanced SLAM algorithms to autonomous robots was a well-established practice. Both Olson and Stachniss described their methods as suitable for various robot types and sensors, and Fong's robot already included the necessary components (processor, memory, sensors) for such an integration.

  • Additional Grounds: Petitioner asserted additional obviousness challenges against claims 1-18 based on combinations of Olson or Stachniss with Schnittman (Patent 9,020,637), which disclosed using ray-tracing to update a particle map for autonomous navigation.

4. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-18 of the ’325 patent as unpatentable under 35 U.S.C. §§ 102 and 103.