DCT
2:23-cv-00517
Tonal Systems Inc v. Shenzhen Speediance Living Technology Co Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Tonal Systems, Inc. (Delaware)
- Defendant: Shenzhen Speediance Living Technology Co., Ltd. (China)
- Plaintiff’s Counsel: Morrison & Foerster LLP
- Case Identification: 2:23-cv-00517, E.D. Tex., 11/08/2023
- Venue Allegations: Venue is alleged as proper for a foreign corporation under 28 U.S.C. § 1391(c), based on Defendant's alleged sale and shipment of the accused product into Texas.
- Core Dispute: Plaintiff alleges that Defendant’s "Gym Monster" digital strength training system infringes six patents related to dynamic resistance control, user-interactive workouts, safety features, and accessory connectors.
- Technical Context: The technology relates to the field of smart home gyms, which use digitally controlled electromagnetic motors to provide resistance as an alternative to traditional physical weights.
- Key Procedural History: The complaint alleges that Plaintiff provided Defendant with a letter notifying it of the asserted patents and its alleged infringement on November 7, 2023, one day prior to filing the complaint. This notification serves as the basis for the allegations of willful infringement.
Case Timeline
| Date | Event |
|---|---|
| 2008-11-16 | U.S. Patent No. 8,287,434 Priority Date |
| 2012-10-16 | U.S. Patent No. 8,287,434 Issues |
| 2013-08-05 | U.S. Patent No. 9,101,791 Priority Date |
| 2015-08-11 | U.S. Patent No. 9,101,791 Issues |
| 2016-07-25 | U.S. Patent No. 10,661,112 Priority Date |
| 2016-07-25 | U.S. Patent No. 11,389,687 Priority Date |
| 2018-03-29 | U.S. Patent No. 10,960,258 Priority Date |
| 2018-03-29 | U.S. Patent No. 11,554,287 Priority Date |
| 2020-01-01 | Defendant Speediance Founded (approx.) |
| 2020-05-26 | U.S. Patent No. 10,661,112 Issues |
| 2021-03-30 | U.S. Patent No. 10,960,258 Issues |
| 2022-07-19 | U.S. Patent No. 11,389,687 Issues |
| 2023-01-17 | U.S. Patent No. 11,554,287 Issues |
| 2023-11-07 | Plaintiff Sends Notice Letter to Defendant |
| 2023-11-08 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,661,112 - "Digital Strength Training"
- Issued: May 26, 2020
The Invention Explained
- Problem Addressed: The patent describes the limitations of traditional strength training, which relies on gravity and physical weights. These systems are not easily adaptable, cannot change resistance mid-movement to implement advanced protocols (like eccentric loading), and are often bulky (’112 Patent, col. 3:9-4:59).
- The Patented Solution: The invention is a digital strength trainer that replaces physical weights with an electric motor coupled to a cable and a user-operated actuator (e.g., a handle). A key component is a "filter"—a set of software instructions—that receives information about the actuator's position and provides input to a motor controller. This allows the system to dynamically adjust the motor's torque to implement specific "strength curves," thereby simulating various workout modes not easily replicated with physical weights (’112 Patent, Abstract; col. 5:25-47; Fig. 1A).
- Technical Importance: This approach enables the creation of compact, digitally controlled exercise equipment that can instantaneously vary resistance, allowing for more efficient, effective, and versatile workout protocols (’112 Patent, col. 5:1-24).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶38).
- Essential elements of claim 1 include:
- An actuator;
- A motor, wherein the motor is of pancake style and the machine is of low relative depth;
- A cable coupled between the actuator and the motor;
- A motor controller coupled to the motor; and
- A filter coupled to the motor controller, configured to receive position information and provide an input to the controller to adjust motor torque according to a strength curve, which comprises comparing the relative motor-actuator position and sending pulses to adjust the motor's position.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 8,287,434 - "Method and Apparatus for Facilitating Strength Training"
- Issued: October 16, 2012
The Invention Explained
- Problem Addressed: The patent notes that conventional exercise can be monotonous and lacks immediate, intelligent feedback. Furthermore, traditional equipment does not easily accommodate advanced training techniques where resistance might need to vary during a single repetition (’434 Patent, col. 2:50-60).
- The Patented Solution: The invention discloses a method where a "video gaming system" facilitates a strength training exercise. The system communicates with an exercise device to set a resistance force, monitors the user's progress, and supplies video or audio feedback. Crucially, the system allows the resistance force to be adjusted such that a user can experience two substantially different force magnitudes at substantially the same position within the movement, enabling protocols like eccentric loading (’434 Patent, Abstract; col. 4:1-15).
- Technical Importance: The invention integrates interactive digital content with automated resistance control, creating a more engaging user experience and enabling sophisticated, dynamically adjusted workout protocols (’434 Patent, col. 2:1-10).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶70).
- Essential elements of claim 1 include:
- Communicating a first information indicative of a resistance force with an exercise device;
- Monitoring progress of the strength training exercise;
- Supplying information for a video or an audio signal indicative of the exercise progress; and
- The resistance force being adjustable to provide a first magnitude and a substantially different second magnitude at substantially the same position during the movement.
- The complaint does not explicitly reserve the right to assert dependent claims for this patent.
U.S. Patent No. 10,960,258 - "Exercise Machine Connector"
- Issued: March 30, 2021 (Compl. ¶30)
- Technology Synopsis: The technology addresses the need for a safe and convenient mechanism to attach different accessories (e.g., handles, bars) to the end of an exercise machine's cable (’258 Patent, col. 2:35-42). The patented solution is a connector with a chamber that receives a "key" from an accessory. A biasing mechanism within the chamber presses the key against a receiving groove to securely lock it in place, preventing accidental detachment during use (’258 Patent, Abstract).
- Asserted Claims: At least independent claim 1 (Compl. ¶91).
- Accused Features: The connector on the Speediance Gym Monster's cable, which is alleged to use a key, chamber, biasing mechanism, and receiving groove to attach accessories (Compl. ¶¶93-101).
U.S. Patent No. 11,554,287 - "Exercise Machine Connector"
- Issued: January 17, 2023 (Compl. ¶31)
- Technology Synopsis: This patent, related to the ’258 Patent, also discloses a connector for exercise machine accessories. The claims focus on a chamber located within a cable connection base that is adapted to receive a key, where the key itself includes an eyelet through which a fastener can be attached (’287 Patent, Abstract).
- Asserted Claims: At least independent claim 1 (Compl. ¶112).
- Accused Features: The same Speediance connector, which is alleged to have a chamber within its main body and a key featuring a hole (eyelet) that allows for the attachment of a strap or other fastener (Compl. ¶¶117-119).
U.S. Patent No. 11,389,687 - "Digital Strength Training"
- Issued: July 19, 2022 (Compl. ¶32)
- Technology Synopsis: This patent, related to the ’112 Patent, discloses an automated "spotter" safety feature for a digital strength training machine. The invention uses a processor to monitor the user's performance, specifically to detect a state of struggle, which it defines as the persistence of both low cable velocity and high cable tension within a pre-determined range of motion. In response, the system automatically reduces the motor's torque to assist the user (’687 Patent, Abstract).
- Asserted Claims: At least independent claim 1 (Compl. ¶133).
- Accused Features: The "Spotter" mode of the Speediance Gym Monster, which allegedly determines the user's range of motion, detects persistent low-velocity/high-tension conditions, and reduces motor torque to assist the user in completing a repetition (Compl. ¶¶144-152).
U.S. Patent No. 9,101,791 - "Systems and Methods for Optimizing Muscle Development"
- Issued: August 11, 2015 (Compl. ¶33)
- Technology Synopsis: This patent describes a method for generating data-driven, personalized exercise programs. The system identifies user parameters (e.g., fitness goals) and measures force data from the user performing an initial exercise. Based on this data, a processing device computes a recommended resistance for an exercise program by multiplying the measured force by a fractional multiplier that is selected based on the user's parameters (’791 Patent, Abstract).
- Asserted Claims: At least independent claim 1 (Compl. ¶163).
- Accused Features: The Speediance system's process of conducting a "strength assessment" to measure a user's force data and then using that data, along with user-provided parameters, to generate and recommend specific resistance levels for exercises (Compl. ¶¶166-175).
III. The Accused Instrumentality
- Product Identification: The accused product is the Speediance Gym Monster (Compl. ¶18).
- Functionality and Market Context: The complaint describes the Gym Monster as a digital strength training machine that uses an electric motor system to provide resistance (Compl. ¶20). Key accused functionalities include its "adaptive weight modes" such as "Chain," "Eccentric," and "Spotter" modes, which dynamically adjust resistance during an exercise (Compl. ¶22). The device includes a tablet for displaying interactive video content, tracking workout progress, and performing a "strength assessment" to set resistance levels (Compl. ¶21). The system also features a proprietary connector for attaching various accessories like handles and barbells (Compl. ¶23). A screenshot in the complaint shows the product's "Training Mode" selection screen, which includes options for "Standard," "Chain," "Eccentric," and "Constant" dynamic weight modes (Compl. p. 22). The complaint alleges that Speediance markets the product as a "Tonal killer" and directly targets Tonal's customers (Compl. ¶20).
IV. Analysis of Infringement Allegations
10,661,112 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an actuator | The product includes various actuators that the user can use to move the cables, such as handles, a barbell, and a tricep rope. | ¶42 | col. 5:35-39 |
| a motor, wherein the motor is of pancake style and the machine is of low relative depth | The product has a slim profile and utilizes two compact "pancake style motors that are higher in diameter and lower in depth." A technical animation of these motors is referenced. | ¶¶44-45 | col. 16:58-63 |
| a cable coupled between the actuator and the motor | The product includes a cable that is coupled to an actuator on one end and to the motor on the other end. | ¶47 | col. 5:32-35 |
| a motor controller coupled to the motor | The product's "digital weight system" effectuates digital controls through one or more controller circuits that are coupled to and control the motors. | ¶49 | col. 5:29-31 |
| a filter coupled to the motor controller, configured to: receive an information related to the position of the actuator | The product's filter receives information related to the actuator's position to determine the user's range of motion. A screenshot shows a "Range of Motion" graph generated by the system. | ¶54 | col. 5:40-42 |
| and provide an input to the motor controller to adjust torque on the motor such that a strength curve is implemented relative to the position of the actuator, comprising to: | When a user chooses a resistance mode (e.g., "chains"), the filter provides input to the motor controller to adjust torque and implement the appropriate strength curve based on the chosen mode and actuator position. | ¶56 | col. 5:42-47 |
| compare a current relative position between the motor and the actuator | The product provides a range of motion graph that compares, throughout the exercise, the current relative position between the motor and the actuator. | ¶¶57-58 | col. 5:44-47 |
| and send an appropriate number of pulses to the motor to adjust a position of the motor based on the current relative position between the motor and the actuator. | The filter instructs the controller circuit to send electric pulses to its permanent magnet synchronous motors to control the motor's position and generate the appropriate resistance. | ¶60 | col. 14:13-17 |
- Identified Points of Contention:
- Scope Questions: A potential point of dispute may be the construction of "pancake style." The infringement allegation relies on a functional description ("higher in diameter and lower in depth"), and the question for the court may be whether this term carries a more specific technical meaning that the accused motors do or do not meet (Compl. ¶45).
- Technical Questions: The complaint alleges that the filter "sends pulses to the motor to control the motor's position" based on the general operating principle of the identified motor type (PMSM) (Compl. ¶60). A question may arise as to what specific evidence demonstrates that the accused device implements this claimed control method, as opposed to other methods of controlling motor torque.
8,287,434 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| communicating a first information with an exercise device, the first information indicative of a resistance force during said strength training exercise | The product's tablet contains a processor that communicates the appropriate resistance information to the motors of the exercise machine. | ¶75 | col. 4:1-4 |
| monitoring progress of said strength training exercise | The tablet monitors the user's progress by tracking metrics such as repetition count, resistance, and range of motion. The complaint includes a screenshot showing the system tracking reps and weight. | ¶77 | col. 4:5-6 |
| supplying information for a video or an audio signal indicative of the exercise progress | The tablet provides "a counting sound" for each repetition and a visual display of the total repetitions completed versus the total repetitions in the set. | ¶79 | col. 4:7-9 |
| wherein said resistance force can be adjusted, so there is a first magnitude of the resistance force associated with a position during exercise movement, and a second magnitude of the resistance force associated with substantially the same position, the first magnitude substantially different from the second magnitude. | The product's "Eccentric Mode" is alleged to increase resistance as the user returns to the starting position. This creates a first resistance during the concentric phase and a substantially different, higher resistance at the same position during the eccentric phase. | ¶81 | col. 4:10-15 |
- Identified Points of Contention:
- Scope Questions: The claim requires a "video gaming system." A central question may be whether the accused product—an integrated smart exercise machine with a tablet—falls within the scope of this term as it would have been understood at the time the patent was filed.
- Technical Questions: What evidence does the complaint provide that the "Eccentric Mode" actually results in a "substantially different" magnitude of resistance force at "substantially the same position"? The allegation is based on marketing descriptions of the feature's function rather than empirical force curve data (Compl. ¶81).
V. Key Claim Terms for Construction
For the ’112 Patent:
- The Term: "filter"
- Context and Importance: This term is the core of the invention's control system, defining how the digital brain translates user position into motor torque. Its construction will be critical, as Defendant may argue its control software does not meet the definition of the claimed "filter."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification provides a broad definition, stating that the equations by which the controller is configured to drive the motor "are collectively referred to as a 'filter'" (’112 Patent, col. 7:51-54).
- Evidence for a Narrower Interpretation: The detailed description focuses heavily on specific, named filters such as the "Constant Torque Filter" and the "Weight Stack Filter," which are defined by detailed physics equations that model traditional weights (’112 Patent, col. 7:15-31). This may suggest a narrower scope limited to software that mathematically models physical systems.
For the ’434 Patent:
- The Term: "video gaming system"
- Context and Importance: The entire method of claim 1 is performed by a "video gaming system." The viability of the infringement claim hinges on whether the accused Gym Monster product, with its integrated tablet, qualifies as such a system.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent defines the term broadly as "an interactive entertainment computer or electronic device that produces a video display signal which can be used with a display device (a television, monitor, etc.)" (’434 Patent, col. 4:50-54). This language could support reading the term on any modern device with a screen and interactive software.
- Evidence for a Narrower Interpretation: The patent's background section explicitly discusses systems like the Nintendo Wii and Microsoft Kinect, distinguishing them from exercise equipment with embedded computers (’434 Patent, col. 1:17-35). This context could support an argument that the term was meant to cover general-purpose gaming consoles connected to exercise equipment, not integrated systems.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement for all six asserted patents. The factual basis for inducement is Defendant's alleged encouragement and instruction for customers to use the infringing features through materials such as its website, Amazon product pages, and user manuals (Compl. ¶¶ 26, 37, 69, 90, 111, 132, 162).
- Willful Infringement: The complaint alleges willful infringement for all six asserted patents. The basis for willfulness is alleged pre-suit knowledge stemming from a notice letter Plaintiff delivered to Defendant on November 7, 2023, the day before the complaint was filed (Compl. ¶¶ 25, 61, 82, 103, 124, 154, 176).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of functional equivalence: does the evidence show that the accused product's software features, such as its "Spotter" and "Eccentric" modes, operate in the specific manner required by the patent claims (e.g., by detecting persistent low-velocity/high-tension states, or by sending pulses to adjust motor position), or is there a material difference in their technical implementation?
- A second key issue will be one of definitional scope: can claim terms like "filter" and "video gaming system," which are rooted in the patents' specific disclosures and the technological context of their filing dates, be construed broadly enough to encompass the integrated hardware and software architecture of the accused smart gym?
- A third central question will concern mechanical operation: for the connector patents, the dispute will likely turn on a detailed analysis of the accused connector's components to determine if its biasing mechanism interacts with a "receiving groove" to securely fix a key in the precise manner recited by the claims.