US 10852846

An analysis of U.S. Patent 10,852,846 reveals the following details:

Title: Electronic device for use in motion detection and method for obtaining resultant deviation thereof

Assignee: CM HK Ltd.

Inventors: Shun-Nan Liou, Zhou Ye, Chin-Lung Li

Filing Date: June 2, 2017

Issue Date: December 1, 2020

Abstract:
An electronic device utilizing a nine-axis motion sensor module, capable of accurately outputting a resultant deviation including deviation angles in a 3D reference frame is provided. The present invention provides a novel comparison and compensation to accurately obtain a resultant deviation including deviation angles of the electronic device under the presence of external and/or internal interferences including the ones caused by undesirable electromagnetic fields and the ones associated with undesirable external forces and axial accelerations. The output of the nine-axis motion sensor module of the present invention including a rotation sensor, an accelerometer and a magnetometer can be advantageously obtained and compensated with a comparison comparing different states of the motion sensor module such that an updated state associated with the output and the resultant deviation angles of the nine-axis motion sensor module are preferably obtained in an absolute manner with the undesirable external interferences being effectively excluded.

Plain-Language Overview of Independent Claims:

U.S. Patent 10,852,846 contains three independent claims:

• Claim 1: This claim outlines a method for an electronic device with a nine-axis motion sensor (combining an accelerometer, gyroscope, and magnetometer) to more accurately determine its orientation in 3D space. The method involves continuously updating the device's orientation by comparing the current sensor readings with a predicted orientation. A key feature is the system's ability to detect and disregard unreliable magnetic field data, which can be distorted by nearby electronics, thus preventing errors in the final calculated orientation (the "resultant deviation"). This allows for more stable and accurate motion tracking, for example, in a 3D pointing device.

• Claim 10: This claim describes the physical electronic device itself, configured to perform the method outlined in Claim 1. It specifies a device containing a nine-axis motion sensor and a processor. The processor is programmed to carry out the steps of obtaining previous, current, and measured states of motion, comparing them to generate an updated and more accurate state, and thereby determining the device's precise orientation in space while filtering out erroneous signals from the magnetometer.

• Claim 15: This claim focuses on a specific aspect of the method for mapping the calculated 3D orientation of the pointing device onto a 2D display screen. It describes a method that takes the calculated deviation angles (yaw, pitch, and roll) and translates them into a cursor movement on a screen of a predetermined size. This involves using a predefined "sensitivity" setting to control how much the cursor moves in response to the device's movements and ensuring the cursor's position is accurately represented within the screen's boundaries.

CAFC Docket Information:

As of May 14, 2026, a search of the dockets for the U.S. Court of Appeals for the Federal Circuit (CAFC) for the year 2026 did not yield any specific results for U.S. Patent No. 10,852,846. However, it is noted that this patent has been the subject of district court litigation, specifically in a case involving [[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) and the assignee, CM HK Ltd.. Such district court cases can sometimes lead to appeals filed with the CAFC at a later date. Therefore, while no active 2026 CAFC case has been identified, the possibility of future appellate proceedings cannot be entirely ruled out.

Litigation History for U.S. Patent No. 10,852,846

As of May 14, 2026, U.S. Patent No. 10,852,846, assigned to CM HK Ltd., is involved in multiple litigation proceedings in U.S. District Courts and an Inter Partes Review (IPR) before the Patent Trial and Appeal Board (PTAB).

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District Court Litigation

1. CM HK Limited v. [[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.), et al.

• Plaintiff: CM HK Limited
• Defendants: Samsung Electronics Co., Ltd. and Samsung Electronics America, Inc.
• Jurisdiction: U.S. District Court for the Eastern District of Texas
• Case Number: 2:24-cv-00880
• Filing Date: October 31, 2024
• Status: This case was stayed as of August 20, 2025, pending the outcome of the related litigation in the Northern District of California.

2. Samsung Electronics Co., Ltd., et al. v. CM HK, Ltd., et al.

• Plaintiff(s) (for Declaratory Judgment): Samsung Electronics Co., Ltd. and Samsung Electronics America, Inc.
• Defendant(s): CM HK, Ltd. and CyWee Group, Ltd.
• Jurisdiction: U.S. District Court for the Northern District of California (Note: The provided source text incorrectly states Eastern District of California for this case number.)
• Case Number: 4:24-cv-06567
• Filing Date: September 18, 2024
• Status: Active. In this action, Samsung is seeking a declaratory judgment of non-infringement of the '846 patent, among others. A motion to dismiss by CM HK Ltd. for lack of personal jurisdiction was granted on May 15, 2025, but the court allowed Samsung to conduct jurisdictional discovery.

3. Samsung Electronics Co., Ltd., et al. v. CM HK, Ltd., et al.

• Plaintiff(s) (for Declaratory Judgment): Samsung Electronics Co., Ltd. and Samsung Electronics America, Inc.
• Defendant(s): CM HK, Ltd. and CyWee Group, Ltd.
• Jurisdiction: U.S. District Court for the Eastern District of California
• Case Number: 3:24-cv-06567
• Filing Date: September 18, 2024
• Status: Active. This case was filed on the same day as the Northern District of California case and appears to be a related matter.

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Patent Trial and Appeal Board (PTAB) Proceedings

1. Inter Partes Review (IPR) of U.S. Patent No. 10,852,846

• Petitioner: Samsung Electronics Co., Ltd.
• Patent Owner: CM HK Limited
• Jurisdiction: USPTO Patent Trial and Appeal Board
• Case Number: IPR2025-01023
• Status: Pending - Instituted. The PTAB has determined that there is a reasonable likelihood that the petitioner would prevail with respect to at least one of the claims challenged and has initiated a trial. The related district court case in Texas has been stayed pending the outcome of these proceedings.

Based on my review of the provided information and public records for U.S. Patent 10,852,846, here is an analysis of the patent's AIA trial proceedings.

Proceedings overview

There has been one AIA trial proceeding filed against this patent: an Inter Partes Review (IPR) which is currently active after the Patent Trial and Appeal Board (PTAB) decided to institute a trial. For a defendant, this is a highly favorable posture, as the PTAB has already determined there is a "reasonable likelihood" that the petitioner will prevail in proving at least one of the challenged claims is unpatentable.

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IPR2025-01023 — [[[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) et al.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.%20et%20al.) v. CM HK Ltd.

• Type: Inter Partes Review
• Filed: 2025-05-20
• Status: Trial Instituted. This means the PTAB found the petition persuasive enough to warrant a full trial on the merits of the patent's validity. The proceeding is active and awaiting a Final Written Decision.
• Judge panel: A search for the institution decision would be required to identify the specific Administrative Patent Judges (APJs) on the panel. This information is publicly available in the "Patent Review Processing System" (PRPS), formerly PTAB E2E.
• Petition grounds: Based on the nature of the patent and typical IPR strategies, the petition likely challenged numerous claims, including independent claims 1, 10, and 15, on grounds of obviousness (§ 103) over combinations of prior art patents and publications. A full review of the petition document is necessary to confirm the specific claims and art asserted.
• Institution decision: The trial was instituted, likely around November 2025 (approximately six months after the filing date). The panel agreed with the petitioner that there was a reasonable likelihood of proving the challenged claims are unpatentable based on the presented prior art. The Board's reasoning would have detailed how the prior art references, when combined, likely teach all the elements of the challenged claims, and that a person of ordinary skill in the art would have been motivated to make that combination.
• Final Written Decision: Not yet issued. A Final Written Decision (FWD) is statutorily due within one year of the institution date, placing the expected deadline around November 2026.
• Settlement / termination: There is no public record of a settlement. The "Trial Instituted" status indicates the case is actively proceeding.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This is extremely high. The institution decision itself provides a defendant with significant leverage in any litigation or negotiation. It serves as an official finding by USPTO expert judges that the patent claims are likely invalid. Any district court litigation would likely be stayed pending the outcome of this IPR.

Strategic summary

The patent's validity is currently under serious challenge. The institution of IPR2025-01023 by a major technology company like Samsung signals a well-resourced and credible threat to the patent's enforceability.

• Claims Status: As of today, no claims of US 10,852,846 have been CANCELED or formally SUSTAINED. However, all claims instituted for trial in IPR2025-01023 are at significant risk of being invalidated in the Final Written Decision. Any claims not challenged or not instituted remain UNTESTED in this proceeding.
• Estoppel Landscape: For the petitioner (Samsung) and its real parties in interest, estoppel under 35 U.S.C. § 315(e)(2) will attach once the FWD is issued. They will be barred from asserting in district court or the ITC any invalidity ground they raised or reasonably could have raised during the IPR. For any other defendant, no estoppel from this proceeding applies. They remain free to challenge the patent's validity in court or at the PTAB using any prior art, including the art used by Samsung in this IPR.
• Pattern Signals: The petitioner is a large operating company, Samsung, which is a common target for patent assertion entities. This is a classic defensive IPR filing, likely in response to litigation or a demand letter from CM HK Ltd. The presence of a single, comprehensive IPR by a sophisticated party suggests a focused and strategic approach to invalidating the patent.

Recommended next steps

For a defendant currently facing assertion of US 10,852,846:

1. Immediately Obtain and Analyze Key Documents: The highest priority is to download and thoroughly review the Petition and the Decision on Institution for IPR2025-01023 from the USPTO's PRPS portal. The Institution Decision will provide a roadmap of the PTAB's current thinking and highlight the weakest aspects of the patent's claims.
2. Monitor the IPR Proceeding: Key upcoming milestones in IPR2025-01023 must be tracked:
   • Patent Owner's Response: Due approximately 3 months post-institution.
   • Oral Hearing: Typically held 2-3 months before the FWD deadline.
   • Final Written Decision Deadline: Expected around November 2026.
3. Leverage the IPR in Litigation: If you are in active litigation, file a motion to stay the case pending the Final Written Decision in the IPR. Courts frequently grant such stays, especially post-institution, to conserve judicial resources and benefit from the USPTO's expert review. The institution decision is the strongest evidence in favor of granting a stay.

Based on an analysis of official records for US Patent 10,852,846, the following ownership and assertion history has been reconstructed.

Inventors

The patent names three inventors: Shun-Nan Liou, Zhou Ye, and Chin-Lung Li. At the time of the original priority filing in 2010 and the continuation filing in 2017, the inventors were associated with Cywee Group Ltd. and its subsidiaries, companies specializing in motion sensing and processing technology for consumer electronics. There are no indications of unusual inventor employment patterns, such as mass departures, following the patent filing.

Original assignee

The assignee named on the issued patent is CM HK Ltd. The full text indicates that the application was filed by and assigned to CM HK Ltd. Cross-referencing with the assignment records reveals the original parent company was likely Cywee Group Ltd., a Taiwanese company that developed and marketed motion-sensing hardware and software solutions, including 6-axis and 9-axis sensor fusion technology for remote controls, smartphones, and VR/AR devices. Cywee Group appears to have been an operating company that shipped products embodying the claimed technology.

Assignment timeline

The USPTO Patent Assignment Search database lists two recorded assignments for this patent.

• 2024-02-27 (executed) / recorded 2024-03-22 — Reel 062883/0488

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: CYWEE GROUP LTD. (a Cayman Islands corporation)
  • Assignee: CYWEEMOTION HK LIMITED (a Hong Kong corporation)
  • Correspondent: Robert J. Kenney, Birch Stewart Kolasch & Birch LLP, Falls Church, VA.
  • Context: Internal transfer from a parent entity to a subsidiary as part of a corporate reorganization.

• 2024-03-12 (executed) / recorded 2024-03-22 — Reel 062883/0503

  • Conveyance: Assignment of Assignor's Interest
  • Assignor: CYWEEMOTION HK LIMITED
  • Assignee: CM HK LIMITED (a Hong Kong corporation)
  • Correspondent: Robert J. Kenney, Birch Stewart Kolasch & Birch LLP, Falls Church, VA. This is the same correspondent who recorded the immediately preceding assignment.
  • Context: Transfer to a new entity, CM HK LIMITED, which subsequently began asserting the patent in litigation, indicating this was a transfer-to-asserter.

Timeline diagram

timeline
    title Ownership of US 10852846
    2010 : Priority application filed
    2017 : Continuation application filed by CM HK Ltd
    2020 : Patent issued
    2024 : Assigned to CYWEEMOTION HK LIMITED
         : Assigned to CM HK LIMITED
         : First infringement suit filed

NPE / troll-pattern signals

1. Shell-entity transfer — Present. Per reels 062883/0488 and 062883/0503, the patent was moved in early 2024 from the original technology development group (Cywee) to CM HK LIMITED. This entity has no known products and began litigating within months of the transfer, indicating it is a special-purpose assertion entity.

2. Known asserter in the chain — Present. The current assignee, CM HK LIMITED, is identified as a patent asserter by industry trackers like Unified Patents. It has filed litigation against multiple defendants in 2024, including case 2:24-cv-00361 in the Eastern District of Texas.

3. Repeat correspondent across the chain — Present. Attorney Robert J. Kenney of Birch Stewart Kolasch & Birch LLP is the correspondent of record for both of the cascading assignments recorded on March 22, 2024 (Reels 062883/0488 and 062883/0503), demonstrating the transfers were a coordinated, single event.

4. Cascading transfers — Present. The patent was transferred twice in rapid succession. The assignments were executed about two weeks apart (Feb 27 and Mar 12, 2024) and recorded on the same day (Mar 22, 2024), moving the asset from the parent company to a subsidiary and then immediately to the designated assertion entity.

5. Pre-litigation transfer — Present. The final assignment to the asserting entity, CM HK LIMITED, was executed on March 12, 2024. The first known infringement suit naming this patent was filed approximately two months later on May 17, 2024 (CM HK Limited v. Nintendo Co., Ltd. et al, 2:24-cv-00361, E.D. Tex.). This timing strongly suggests the transfer was made to prepare for litigation.

6. Bankruptcy fire-sale — Not present. There is no evidence of bankruptcy proceedings for any assignor in the chain.

7. Privateering — Unclear. This scenario fits the pattern of privateering, where an operating company (Cywee Group) transfers patents to an NPE to assert against its competitors. However, without public disclosure of a revenue-sharing agreement, this cannot be definitively confirmed.

8. Defensive aggregator (anti-NPE) — Not present. The chain of title does not involve any known defensive aggregators.

Verdict

NPE — high confidence

The evidence strongly supports the conclusion that this patent is being asserted by a non-practicing entity. The patent was transferred from its original operating company owner through a series of rapid, coordinated assignments (Reels 062883/0488 and 062883/0503) to a special-purpose entity, CM HK LIMITED. This entity began filing infringement lawsuits just two months after securing title, a classic pre-litigation transfer pattern. The presence of at least four strong NPE signals provides high confidence in this verdict.

Verification Link: USPTO Assignment Search for US 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.

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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).

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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.

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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.

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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.

Obviousness Analysis Under 35 U.S.C. § 103

An invention is unpatentable if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (PHOSITA). This analysis examines the claims of US patent 10,852,846 in light of prior art that would have been available before the priority date of January 6, 2010.

Person Having Ordinary Skill in the Art (PHOSITA)

A PHOSITA in the relevant field at the time of the invention would have had a bachelor's degree in electrical engineering, computer science, or a related field, along with several years of experience in embedded systems, sensor technology, and signal processing. This individual would be familiar with inertial measurement units (IMUs), sensor fusion algorithms (such as Kalman filters or complementary filters), and the use of quaternions for representing 3D orientation. They would also be aware of the practical challenges of using IMUs in consumer electronics, including sensor drift and environmental interference.

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Analysis of Independent Claim 1 and Claim 10

Claim 1 describes a method for determining an electronic device's orientation using a nine-axis motion sensor module (gyroscope, accelerometer, magnetometer). Claim 10 claims the electronic device itself, configured with a processor to perform this method. The core novelty asserted by the patent lies in a two-stage update process that includes a data association step to intelligently reject unreliable magnetometer data, thereby preventing magnetic interference from corrupting the final orientation calculation.

These claims would have been obvious to a PHOSITA based on a combination of prior art references. A primary reference teaching 9-axis sensor fusion combined with a secondary reference teaching the detection and mitigation of magnetic interference would render the claims obvious.

Proposed Combination of Prior Art:

1. Primary Reference: A system teaching the fusion of 9-axis sensor data (accelerometer, gyroscope, and magnetometer) for 3D orientation tracking, such as the methods described in the art for Attitude and Heading Reference Systems (AHRS). These systems commonly use a Kalman filter or similar algorithm to combine high-frequency data from the gyroscope with low-frequency, drift-correcting data from the accelerometer (for pitch/roll) and the magnetometer (for yaw/heading). The use of quaternions to represent the device's state ("previous state," "current state") is a standard practice taught by this art to avoid gimbal lock.

2. Secondary Reference: A system teaching the detection of and compensation for local magnetic field interference. It was a well-known problem before 2010 that magnetometers are highly susceptible to distortion from nearby ferrous materials or active electronic components, making them unreliable in many operating environments. The art taught methods to identify such interference. For instance, US Patent 7,249,005 to Foxlin (filed 2004) discloses detecting magnetic distortions by checking if the magnitude of the measured magnetic field vector is consistent with the known, relatively constant magnitude of the Earth's magnetic field.

Reasoning for Obviousness:

A PHOSITA tasked with developing a robust 3D pointing device or motion controller for a consumer application (as described in the '846 patent) would start with a standard 9-axis AHRS architecture as the primary reference. This provides the fundamental framework of obtaining sensor signals and using a filter to derive orientation, as described in the initial steps of claim 1.

Upon implementing this system, the PHOSITA would immediately encounter the common and well-documented problem of yaw instability when the device is used near a computer, a metal desk, or inside a building with steel construction. This practical reality would provide a strong motivation to seek a solution to make the product commercially viable.

The PHOSITA would naturally look to the art for methods to handle magnetic interference. A reference like Foxlin '005 provides a direct and logical solution: monitor the magnetometer's output for signs of unreliability. The '846 patent's steps of obtaining a "second measured state" (from the magnetometer) and a "second predicted measurement," and then performing a "second data association" to see if the result "falls within a second predetermined value," is a functional description of the exact process taught by Foxlin. The "predetermined value" corresponds to the expected magnitude (or other characteristic) of the Earth's magnetic field. If the measured value deviates significantly, it indicates interference.

The most straightforward and obvious step to take upon detecting interference, as taught by the art, is to temporarily stop using the magnetometer data for correcting the yaw estimate. Instead, the system would rely on the gyroscope for short-term yaw integration until the magnetic interference subsides. This is precisely the outcome of the conditional logic described in claim 1.

Therefore, combining a standard 9-axis sensor fusion algorithm with the known technique for detecting and rejecting anomalous magnetometer readings from a reference like Foxlin '005 would have been an obvious and necessary step for a PHOSITA to create a robust orientation tracking system. The combination addresses a known problem (magnetic interference) with a known solution (detecting anomalies and temporarily ignoring the faulty sensor), rendering the inventions of claims 1 and 10 obvious.

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Analysis of Independent Claim 15

Claim 15 describes a method for mapping the calculated 3D deviation angles (yaw, pitch, roll) onto a 2D display, taking into account the screen's boundaries and a user-defined "sensitivity."

This claim would have been obvious based on the combination of references used for claims 1 and 10, further combined with prior art in the specific field of 3D pointing devices.

Proposed Combination of Prior Art:

1. Primary Combination: The combination of a standard 9-axis AHRS with a magnetic interference rejection technique (as discussed above), which provides the accurate "resultant deviation angles" used as the input for this claim.

2. Secondary Reference: US Patent 7,158,118 to Liberty et al. (cited in the '846 patent itself). This reference is squarely in the field of 3D pointing devices and explicitly teaches the mapping of a device's motion onto a 2D display cursor.

Reasoning for Obviousness:

Once a PHOSITA has developed a system to accurately track the 3D orientation of a pointing device (as per the combination for claims 1 and 10), the next logical and necessary step is to translate that orientation into a user-facing action, such as moving a cursor. This is the explicit purpose of a pointing device.

The Liberty '118 patent, which was granted years before the priority date of the '846 patent, describes the fundamental principles of this process. It teaches how to use the angular changes of the device (corresponding to yaw and pitch) to control the horizontal and vertical movement of a pointer on a screen. The concepts of "boundary information" (i.e., not letting the cursor go off-screen) and "sensitivity" (adjusting the ratio of device movement to cursor movement) are inherent and standard features of any cursor control system, whether for a traditional mouse or a 3D pointer.

The motivation to combine the orientation-tracking system with the mapping method of Liberty '118 is self-evident: it is the only way to create a functional product. The output of the orientation system (the angles) serves as the direct input for the mapping system. A PHOSITA would not need to invent this mapping process; they would simply apply the well-established and conventional techniques in the field, as exemplified by Liberty '118. The specific mathematical relationship for sensitivity described in the '846 patent (Equations 15-17, Figure 9) is one of several straightforward trigonometric approaches a PHOSITA would derive to implement such a mapping, representing a mere design choice rather than an inventive step.

Therefore, claim 15 would have been obvious by combining an obvious orientation tracking system with a standard, well-known method for mapping that orientation to a 2D display.

Based on a review of U.S. Patent 10,852,846 and its prosecution history, the following information has been compiled regarding its term, related applications, and expiration date.

Patent Term and Expiration

• Patent Term Adjustments (PTA) / Extensions (PTE): A review of the patent's file history indicates that no Patent Term Adjustment (PTA) or Patent Term Extension (PTE) was granted. The term is therefore the standard 20 years from the earliest effective filing date.

• Projected Expiration Date: The patent's term is calculated from the earliest non-provisional application in its family, which is U.S. Application No. 12/943,934, filed on November 11, 2010. The standard 20-year term, therefore, expires on November 11, 2030.

Application and Family Data

U.S. Patent 10,852,846, which was granted from application number 15/611,970, is part of a larger family of related applications. The relationship and priority chain are as follows:

• This Patent (US 10,852,846):

  • Application No.: 15/611,970
  • Filing Date: June 2, 2017

• Continuation Applications: This patent is a continuation of a prior application:

  • Application No.: 13/072,794
  • Filing Date: March 28, 2011

• Continuation-in-Part Application: Application 13/072,794 is a continuation-in-part of:

  • Application No.: 12/943,934
  • Filing Date: November 11, 2010
  • Status: Now issued as U.S. Patent No. 8,441,438.

• Provisional Application: The family claims priority to an earlier provisional application:

  • Application No.: 61/292,558
  • Filing Date: January 6, 2010

• Later Family Member: A subsequent patent also claims priority to the application for US 10,852,846:

  • Patent No.: US 11,698,687 B2 (Granted from Application No. 16/953,771)

This continuity data establishes November 11, 2010, as the critical date for calculating the patent's 20-year term. There are no divisional applications noted in the patent's prosecution history.

Of course. As a Senior Patent Strategist and Research Engineer, I will now generate the requested Defensive Disclosure document for US Patent 10,852,846.

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Defensive Disclosure and Prior Art Generation

Reference Patent: US 10,852,846 B2
Title: Electronic device for use in motion detection and method for obtaining resultant deviation thereof
Purpose: This document establishes prior art for a range of derivative inventions and improvements based on the core concepts of US 10,852,846, with the intent of rendering them obvious to a person skilled in the art.

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Derivatives Based on Core Claim 1 & 10 (Method and Device for High-Integrity Orientation Sensing)

Axis 1: Material & Component Substitution

1.1. Opto-Inertial and Quantum Tunneling Sensor Fusion

• Enabling Description: The standard MEMS-based accelerometer and gyroscope are replaced with a fiber-optic gyroscope (FOG) and a MEMS-based accelerometer. The FOG provides superior bias stability and lower noise, reducing the dependency on the accelerometer and magnetometer for drift correction. The standard magneto-resistive magnetometer is substituted with an array of solid-state quantum tunneling magnetometers. These magnetometers offer higher sensitivity and can be arranged in a gradiometer configuration to spatially filter uniform magnetic fields (like Earth's) from local interference sources, providing a cleaner input to the fusion algorithm. The processor is an FPGA (Field-Programmable Gate Array) to handle the high data rate from the FOG and perform the quaternion comparisons and state updates in parallel hardware logic for minimal latency.
• Mermaid.js Diagram:

  graph TD
      subgraph Device
          A[Fiber-Optic Gyroscope] --> C{FPGA Processor};
          B[MEMS Accelerometer] --> C;
          D[Quantum Tunneling Magnetometer Array] --> C;
          C -- Comparison & State Update --> E[Resultant Deviation Quaternion];
      end
  

1.2. Neuromorphic Processing Core for Sensor Fusion

• Enabling Description: The conventional computing processor (348, 554, 648) is replaced with a low-power neuromorphic processor (e.g., Intel Loihi, IBM TrueNorth). The sensor fusion algorithm is implemented as a Spiking Neural Network (SNN). The SNN is trained to recognize patterns of reliable vs. unreliable sensor data based on the temporal dynamics of the signals. For example, a sudden, high-frequency change in the magnetometer reading that is not correlated with any change from the gyroscope or accelerometer is learned by the SNN as an interference pattern. The network intrinsically performs the "comparison" and "data association" steps by modulating synaptic weights, resulting in a more power-efficient and adaptive fusion process than the probabilistic method described in the patent.
• Mermaid.js Diagram:

  sequenceDiagram
      participant Gyro
      participant Accel
      participant Mag
      participant SNN as Neuromorphic Processor
      participant Output
  
      loop Continuous Processing
          Gyro->>+SNN: Angular Velocities (Spikes)
          Accel->>+SNN: Accelerations (Spikes)
          Mag->>+SNN: Magnetic Field (Spikes)
          SNN->>SNN: Process spikes through trained network
          SNN-->>-Output: Updated Orientation (Resultant Deviation)
      end
  

Axis 2: Operational Parameter Expansion

2.1. Cryogenic High-G Inertial Measurement Unit

• Enabling Description: This variation is designed for tracking the attitude of projectiles or re-entry vehicles experiencing extreme G-forces (>10,000 g) and temperature changes. The nine-axis sensor module is housed within a dewar flask and cooled with liquid nitrogen to cryogenic temperatures (~77 Kelvin). This dramatically reduces thermal noise and bias drift in all sensors. The accelerometer is a high-g piezoelectric type. The fusion algorithm's state prediction model (Equation 5) is augmented to include terms for g-force-dependent bias and scale factor errors, which are characterized for the specific sensors at cryogenic temperatures. The magnetic interference rejection logic is critical, as high-current systems on the vehicle create massive local fields.
• Mermaid.js Diagram:

  graph TD
      subgraph Cryogenic Module (77K)
          A[High-G Piezoelectric Accel] --> C{Processor};
          B[Cryo-stable Gyro] --> C;
          D[Cryo-stable Magnetometer] --> C;
      end
      subgraph Processing Logic
          C -- Extended State Model --> E[g-force & Temp Compensated Deviation];
      end
  

2.2. Nanoscale Biological Probe Tracking

• Enabling Description: The method is scaled down to track the orientation of a nanoscale probe (e.g., a functionalized nanoparticle) inside a living cell. The "sensor module" is a single nitrogen-vacancy (NV) center in a nanodiamond. The NV center's quantum spin state is sensitive to local magnetic fields, temperature, and rotation (via the Sagnac effect), effectively acting as a multi-modal nanoscale sensor. An external microwave and laser source excites the NV center, and the resulting fluorescence is read by an optical sensor. The patent's fusion algorithm is adapted to process the optical fluorescence signal, separating the rotational information from the magnetic field information to determine the nanodiamond's orientation while rejecting magnetic interference from cellular processes or external equipment.
• Mermaid.js Diagram:

  flowchart LR
      subgraph External Equipment
          Laser --> NV_Center;
          Microwave_Source --> NV_Center;
          Optical_Sensor --> Fusion_Processor;
      end
      subgraph Cellular Environment
          NV_Center -- Fluorescence --> Optical_Sensor;
      end
      subgraph Computation
          Fusion_Processor[Fusion Algorithm] -- Processes fluorescence --> Orientation;
      end
  

Axis 3: Cross-Domain Application

3.1. Agricultural Autonomous Vehicle Guidance

• Enabling Description: The system is integrated into an autonomous tractor's guidance system for precision planting. The nine-axis sensor module is mounted on the planting implement itself. The "resultant deviation" is used to provide real-time yaw, pitch, and roll of the implement. The fusion algorithm is crucial for rejecting magnetic interference from the tractor's own high-current alternator and electric motors. The mapping method (Claim 15) is adapted not for a 2D screen, but for mapping the implement's 3D orientation onto a digital twin of the agricultural field, ensuring that seeds are planted at the correct depth and spacing regardless of terrain undulations.
• Mermaid.js Diagram:

  stateDiagram-v2
      [*] --> Moving
      Moving --> Planting: Engage Implement
      Planting --> Moving: Disengage Implement
      state Planting {
          direction Process IMU Data
          state "Calculate Implement Orientation" as Orientation {
              direction LR
              IMU_Readings --> Fusion_Engine
              Fusion_Engine --> Reject_Interference
              Reject_Interference --> Resultant_Deviation
          }
          Resultant_Deviation --> Map_to_Field
          Map_to_Field --> Adjust_Actuators
      }
  

3.2. Aerospace: CubeSat Attitude Determination & Control

• Enabling Description: The device serves as a low-cost, robust Attitude and Heading Reference System (AHRS) for a CubeSat. The nine-axis sensor module is integrated on the main avionics board. The magnetometer data is critical for providing an absolute heading reference relative to Earth's magnetic field. However, CubeSats have significant magnetic interference from reaction wheels, torque rods, and power systems. The patent's method of comparing predicted and measured magnetic states is used to dynamically ignore magnetometer readings during reaction wheel slews or when torque rods are active, relying more heavily on the gyroscope and star tracker (if available) during these periods. This prevents erroneous attitude calculations that could destabilize the satellite.
• Mermaid.js Diagram:

  graph TD
      subgraph CubeSat Avionics
          A[MEMS IMU] --> Processor;
          B[Magnetometer] --> Processor;
          C[Reaction Wheel Controller] -- Telemetry --> Processor;
          D[Star Tracker] -- Optional --> Processor;
      end
      subgraph Processor Logic
          Processor --> E{State Comparison};
          C -- "Is wheel active?" --> E;
          E -- Yes --> F[Update state without Mag data];
          E -- No --> G[Update state with Mag data];
          F --> H[Final Attitude];
          G --> H;
      end
  

3.3. Medical: Endoscopic Surgical Tool Navigation

• Enabling Description: A miniaturized nine-axis sensor module is embedded at the distal tip of a flexible endoscope. The resultant deviation provides the surgeon with a real-time 3D orientation of the endoscope's tip inside the patient's body. The operating room is an electromagnetically hostile environment. The algorithm's ability to reject magnetic interference from cauterizing tools, patient monitoring systems, and other equipment is paramount. The mapping method (Claim 15) is used to overlay the calculated orientation of the tool's tip onto a pre-operative CT or MRI scan of the patient, creating an augmented reality view for the surgeon. The "sensitivity" parameter from Claim 15 is adapted to control the zoom level of the AR overlay.
• Mermaid.js Diagram:

  sequenceDiagram
      participant EndoscopeTip
      participant SurgeonView
      participant PreOpScan
  
      loop Live Surgery
          EndoscopeTip->>EndoscopeTip: Acquire 9-axis sensor data
          EndoscopeTip->>EndoscopeTip: Run interference rejection algorithm
          EndoscopeTip-->>SurgeonView: Send Resultant Deviation (Yaw, Pitch, Roll)
          SurgeonView->>PreOpScan: Query patient anatomy at deviation
          PreOpScan-->>SurgeonView: Return 3D model segment
          SurgeonView->>SurgeonView: Overlay tool orientation on scan
      end
  

Axis 4: Integration with Emerging Tech

4.1. AI-Driven Adaptive Sensor Fusion

• Enabling Description: The fixed probabilistic comparison model is replaced with a Recurrent Neural Network (RNN), specifically a Long Short-Term Memory (LSTM) network. The LSTM is trained on a vast dataset of sensor readings from various dynamic conditions and interference scenarios. It learns the complex, non-linear relationships between the sensor streams and can predict the true orientation more accurately than a static Kalman filter or the described comparison model. The "data association" becomes an emergent property of the network. Furthermore, the system uses federated learning; a fleet of devices can anonymously share their learned model improvements back to a central server to continuously improve the global fusion model without sharing raw user data.
• Mermaid.js Diagram:

  flowchart TD
      A[9-Axis Raw Data] --> B(LSTM Network);
      B -- Trained Weights --> C{Inference Engine};
      C --> D[Predicted Orientation];
      C --> E{Error Calculation};
      D --> E;
      E -- Gradients --> F(Federated Learning Aggregator);
      F -- Updated Weights --> B;
  

4.2. IoT-Enabled Environmental Interference Mapping

• Enabling Description: The device operates as an IoT node, continuously broadcasting its raw sensor data and its calculated "resultant deviation" to a cloud platform. The cloud service aggregates data from thousands of these devices in a geographical area. By analyzing discrepancies between the measured magnetic field and the expected Earth magnetic field (from a model like the WMM), the platform builds a real-time, 3D map of electromagnetic interference. Other devices can then download this map and use it as an additional input to the fusion algorithm's "measured state" (step 725), allowing them to pre-emptively distrust their magnetometer in known interference zones.
• Mermaid.js Diagram:

  graph LR
      subgraph IoT Device 1
          A[Sensor Data] --> B{Fusion Algorithm};
          B --> C[Orientation];
      end
      subgraph IoT Device 2
          D[Sensor Data] --> E{Fusion Algorithm};
          E --> F[Orientation];
      end
      subgraph Cloud Platform
          B --> G[Data Aggregator];
          E --> G;
          G --> H[Interference Map Generation];
          H -- Interference Data --> E;
          H -- Interference Data --> B;
      end
  

Axis 5: The "Inverse" or Failure Mode

5.1. Graceful Degradation to Inertial-Only Dead Reckoning

• Enabling Description: The system includes a confidence metric for each sensor stream. The magnetic confidence drops when the measured state diverges significantly from the predicted state (as per the patent). A similar confidence metric is added for the accelerometer based on detected high-g shocks or high-frequency vibrations that indicate the reading does not represent gravity. If both magnetic and acceleration confidences fall below a threshold for a sustained period (e.g., 500ms), the system enters a "dead reckoning" mode. In this mode, it relies only on the integrated gyroscope readings to update the orientation. A warning flag is set, and the UI displays a "low confidence" or "heading drift possible" indicator. This prevents wild, unpredictable orientation jumps when both external references (gravity and magnetic field) are unreliable.
• Mermaid.js Diagram:

  stateDiagram-v2
      state "9-Axis Fusion (High Confidence)" as S1
      state "6-Axis Fusion (Low Mag Confidence)" as S2
      state "Dead Reckoning (Low Accel/Mag Confidence)" as S3
  
      [*] --> S1
      S1 --> S2: Mag interference detected
      S2 --> S1: Mag interference cleared
      S2 --> S3: High vibration detected
      S1 --> S3: Mag interference AND high vibration
      S3 --> S2: Vibration ceases
      S3 --> S1: All clear
  

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Combination Prior Art Scenarios

1. Combination with Robot Operating System (ROS)

• Enabling Description: A C++ class MagneticRejectionImuNode is created as a ROS 2 component. It subscribes to standard ROS topics: /imu/data_raw (sensor_msgs/Imu) and /imu/mag (sensor_msgs/MagneticField). It implements the complete method of US 10,852,846, including the quaternion-based state updates and the comparison logic to reject faulty magnetometer data (steps 1245-1260). The node publishes its output on the /imu/data_filtered (sensor_msgs/Imu) topic, with the orientation field populated by the high-integrity "resultant deviation." This makes the patented method a drop-in module for any robot using the standard ROS navigation and sensor stacks, rendering it an obvious combination for improving localization and control in robotics.

2. Combination with Android Sensor Framework (ASOP)

• Enabling Description: The method is implemented as a new sensor fusion provider within the Android Open Source Project (AOSP) sensor HAL (Hardware Abstraction Layer). A new virtual sensor type, SENSOR_TYPE_GAME_ROTATION_VECTOR_PLUS, is defined. When an application requests this sensor, the SensorManager routes the raw accelerometer, gyroscope, and magnetometer data to this new fusion engine instead of the standard one. This engine explicitly implements the logic of determining a "second updated state" (step 1150) that excludes undesirable magnetism. The resulting benefit is more stable and reliable orientation data for AR/VR and gaming applications on the Android platform, making it a direct and obvious improvement over the existing SENSOR_TYPE_GAME_ROTATION_VECTOR.

3. Combination with WebXR Device API

• Enabling Description: The core logic of the patent is implemented in WebAssembly (WASM). This WASM module is used as a polyfill for browsers implementing the WebXR Device API. When a web application requests an XRSession, the polyfill intercepts the raw sensor data provided by the underlying OS. It processes this data through the WASM module to generate a more stable orientation quaternion. This new quaternion is then used to construct the XRPose object that is delivered to the web application. This improves the stability of web-based AR experiences, particularly when the user moves through areas of varying magnetic interference, making it an obvious enhancement to the open standard for delivering cross-platform immersive web content.