Prior art — US Patent 10852846

As a senior US patent analyst, I have examined the prior art cited during the prosecution of U.S. Patent 10,852,846 ('846 patent). Below is an analysis of the most relevant references, their disclosures, and their potential to anticipate the claims of the '846 patent under 35 U.S.C. § 102.

Anticipation requires that a single prior art reference discloses, either expressly or inherently, each and every element of a claimed invention. Based on the file history, the examiner cited several references, but the core novelty of the '846 patent appears to be its specific two-step method for updating orientation, which involves sequentially checking the reliability of accelerometer data and then magnetometer data using "data association" models before incorporating them.

Analysis of Cited Prior Art

The following prior art references were cited by the USPTO examiner during the prosecution of the application that led to the '846 patent.

1. U.S. Patent No. 7,158,118 B2 ("Liberty '118")

Full Citation: US 7,158,118 B2, "Pointing device with compensation for roll," assigned to Liberty Media Corporation.
Publication/Filing Dates: Filed Jun 21, 2002; Published Jan 2, 2007.
Brief Description: The Liberty '118 patent describes a 3D pointing device that uses a combination of gyroscopes and accelerometers to control a cursor on a screen. A key aspect is its method for compensating for the "roll" of the device (rotation around the pointing axis). It uses accelerometer data to determine the direction of gravity, which serves as a stable reference to correct for roll-induced errors in the cursor's movement. This allows a change in yaw to be correctly mapped to horizontal cursor movement, regardless of how the user is holding the device.
Potential Anticipation of Claims:
- Claims 1, 10: The Liberty '118 patent does not anticipate claims 1 or 10. The '846 patent explicitly describes and claims a nine-axis sensor module, including a magnetometer, and a method that uses magnetometer data to correct for yaw drift. Liberty '118 focuses on a system with gyroscopes and accelerometers (typically 5-axis) and does not disclose the use of a magnetometer. Furthermore, the '846 patent's specific two-step data association process—first checking accelerometer reliability, then checking magnetometer reliability before updating the orientation quaternion—is absent from Liberty '118. The '846 patent itself criticizes the Liberty approach for being unable to distinguish gravitational acceleration from other forces in dynamic environments (Col. 4, lines 18-28), a problem its own method aims to solve.
- Claim 15: Liberty '118 discloses mapping device motion to a cursor on a display. It discusses translating the device's yaw and pitch into horizontal and vertical cursor offsets. Therefore, it teaches the general concept of mapping 3D angles to a 2D display. However, claim 15 of the '846 patent recites specific steps of "calculating a predefined sensitivity" and "performing angle and distance translation...based on said deviation angles and boundary information." While Liberty '118 discloses the core concept, it may not explicitly detail every step in the manner claimed in claim 15, making a direct anticipation argument weak. The novelty would likely reside in the specific mathematical model for sensitivity and boundary mapping described in the '846 patent (Col. 14, lines 1-40; FIG. 9).

2. U.S. Patent No. 8,441,438 B2 ("Liou '438")

Full Citation: US 8,441,438 B2, "Electronic device for use in motion detection and method for obtaining resultant deviation thereof," assigned to CYWEEMOTION HK LIMITED.
Publication/Filing Dates: Filed Nov 11, 2010; Published May 14, 2013.
Brief Description: The Liou '438 patent is a parent to the '846 patent, as the '846 patent is a continuation of the application that led to this patent. It discloses the core invention: an electronic device with a nine-axis motion sensor (accelerometer, magnetometer, gyroscope) and a method for calculating its orientation. It describes using quaternions to represent orientation and updating this orientation by comparing sensor measurements against predicted values. The method aims to filter out errors from external forces and magnetic interference to produce a stable "absolute" orientation.
Potential Anticipation of Claims:
- Claims 1, 10, 15: As the parent patent, Liou '438 discloses the fundamental technology. The claims of the '846 patent were likely drafted to be narrower and more specific than those in the '438 patent to overcome rejections during prosecution. While the '438 patent teaches the overall system, it would not anticipate the specific combination of limitations recited in the '846 patent's claims. For example, the detailed sequence of performing a first data association on accelerometer data to get a first updated state, followed by a second data association on magnetometer data to get a second updated state, as recited in claim 1 of the '846 patent, represents a specific embodiment that may not have been explicitly claimed in the parent patent. A parent patent does not anticipate a child patent's claims if those claims are narrower and not fully disclosed in the parent's claims.

3. U.S. Patent Application Publication No. 2008/0246736 A1 ("Krah")

Full Citation: US 2008/0246736 A1, "Inertial-based pointing devices," assigned to [Apple Inc.](/litigations/by-plaintiff/Apple%20Inc.)
Publication/Filing Dates: Filed Apr 4, 2007; Published Oct 9, 2008.
Brief Description: Krah describes an inertial-based 3D pointing device using an IMU (Inertial Measurement Unit) that can include accelerometers, gyroscopes, and magnetometers. The disclosure focuses on sensor fusion techniques to combine data from these sensors to accurately track the device's orientation. It discusses using the accelerometer to find the gravity vector for pitch and roll correction and the magnetometer to find the Earth's magnetic field for yaw correction, thus addressing gyroscope drift. It also mentions methods to handle magnetic disturbances.
Potential Anticipation of Claims:
- Claims 1, 10: Krah teaches a nine-axis sensor system and the principle of using accelerometer and magnetometer data to correct gyroscope drift. This covers the general framework of the '846 patent. However, Krah does not appear to disclose the specific two-step data association and conditional updating process that is central to claim 1. Claim 1 requires a determination of whether accelerometer data is reliable before generating a first updated state, and then separately determining if magnetometer data is reliable before generating a second updated state. This specific sequential, conditional logic for sensor fusion is the likely point of novelty over Krah. Krah's disclosure is more general about sensor fusion without mandating this particular algorithm.
- Claim 15: Similar to Liberty, Krah discloses mapping the calculated orientation to cursor movement on a screen. It potentially teaches the elements of claim 15 at a conceptual level, but likely lacks the specific recitation of calculating sensitivity and performing translation based on boundary information as claimed.

4. U.S. Patent No. 6,836,743 B1 ("Sachs")

Full Citation: US 6,836,743 B1, "Device and method for determining the orientation of a mobile object," assigned to InterSense, Inc.
Publication/Filing Dates: Filed Jan 14, 2000; Published Dec 28, 2004.
Brief Description: Sachs discloses a motion tracking system that integrates data from an inertial sensor (gyroscopes) with data from an accelerometer and a magnetometer to determine the orientation of an object. The system uses the accelerometer to measure the direction of gravity and the magnetometer to measure the direction of the Earth's magnetic field. These measurements provide reference vectors to correct for drift in the gyroscopes. The disclosure discusses Kalman filtering as a method for fusing this data.
Potential Anticipation of Claims:
- Claims 1, 10: Sachs teaches the fundamental combination of a nine-axis sensor system for orientation tracking and the use of reference vectors (gravity, magnetic field) to correct drift. It discloses a complete system for orientation tracking. However, like the other references, it does not appear to disclose the specific sequential comparison and conditional update logic of claim 1, where the reliability of each sensor (accelerometer, then magnetometer) is checked via a "data association" step before its data is used to create distinct "first" and "second" updated states. The use of a Kalman filter is a different, though related, sensor fusion approach. The novelty of the '846 patent likely lies in its specific algorithmic implementation, which differs from a standard Kalman filter application.
- Claim 15: This reference is focused on the sensor fusion problem of determining orientation and does not appear to provide significant detail on the subsequent step of mapping that orientation to a 2D display with specific sensitivity and boundary calculations. Therefore, it is unlikely to anticipate claim 15.