Derivative works

This defensive disclosure document provides a comprehensive analysis of US Patent 7,571,014, generating derivative works and technical disclosures intended to be placed in the public domain. The objective is to create a body of prior art that anticipates future incremental improvements, thereby rendering them obvious or non-novel to a person skilled in the art. This disclosure is based on the patent's core claims related to dynamic grouping, synchronization, and volume control of networked media players.

Reference Patent: US 7,571,014
Title: Method and apparatus for controlling multimedia players in a multi-zone system
Publication Date: August 4, 2009
Current Date: May 13, 2026

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Part 1: Derivative Works Based on Dynamic Grouping & Synchronization

This section explores variations on the methods and apparatus for forming and synchronizing groups of players, as described primarily in independent claims 1 and 25.

Axis 1: Material & Component Substitution

Derivative 1.1: Controller with Haptic-Feedback Interface and Solid-State Controls

• Enabling Description: An apparatus for controlling a player network where the primary user input mechanism is a solid-state, force-sensitive, and piezoelectric-driven haptic surface, replacing the physical scroll wheel (250) and buttons (244, 246, 248, 252). When a user navigates a list of players on the screen (242), the haptic surface provides tactile feedback, such as discrete "clicks" when scrolling over an item or a distinct pulse upon selection. Forming a group is initiated by a pressure-sensitive "deep press" on a player designated as the group head. Subsequent players are added by dragging and dropping their icons onto the group head icon. The haptic feedback confirms the "drop" action with a specific vibration pattern. The controller's chassis is constructed from a conductive polymer, enabling capacitive touch sensitivity on its entire surface for secondary commands.
• Mermaid Diagram:

  graph TD
      subgraph Controller Apparatus
          A[User Interaction] --> B{Haptic Surface Processor};
          B -->|Scroll Gesture| C[Generate Virtual Clicks];
          B -->|Deep Press Gesture| D[Select Zone Group Head];
          B -->|Drag-and-Drop Gesture| E[Add Player to Group];
          C & D & E --> F{Command Formatter};
          F --> G[Network Interface];
      end
      G --> H((Network));
      H --> I[Zone Players];
  

Derivative 1.2: Ultra-Low Power E-Ink Controller with Sporadic State Updates

• Enabling Description: A controlling apparatus utilizing a bi-stable electrophoretic display (E-Ink) for the screen (272). The device operates in a quiescent state, consuming near-zero power. It "wakes" and updates the screen only when a change in the multi-zone system is detected via a low-power wake-on-WLAN packet or when a user interacts with its physical buttons. To form a group, the user selects a group head, and the screen performs a full refresh to display eligible players. As players are added, only the region of the screen corresponding to the group list is partially refreshed to minimize power consumption. This design is optimized for environments where the controller is used infrequently and long battery life is paramount. Communication with the players is transactional and asynchronous, rather than maintaining a persistent connection.
• Mermaid Diagram:

  stateDiagram-v2
      [*] --> LowPower_Quiescent: Device Idle
      LowPower_Quiescent --> Wake_On_Event: User Input or Wake-on-WLAN Packet
      Wake_On_Event --> DisplayUpdate: Fetch System State
      DisplayUpdate --> UserInput_Ready: E-Ink Refresh Complete
      UserInput_Ready --> Command_Sent: User Selects Grouping Action
      Command_Sent --> LowPower_Quiescent: Await Next Event
  

Axis 2: Operational Parameter Expansion

Derivative 2.1: Synchronized Control System for High-Frequency Trading (HFT) Algorithms

• Enabling Description: A method for controlling a plurality of algorithmic trading "players" deployed across geographically distributed data centers. A "controller" interface displays a list of available trading algorithms (players). A user selects a primary algorithm as the "zone group head" (e.g., an arbitrage algorithm). The system then displays a list of eligible supplementary algorithms (e.g., liquidity providers, risk-management bots). When grouped, all algorithms are synchronized to a master atomic clock signal (e.g., via PTP - Precision Time Protocol). A "play" command issued to the group head triggers the simultaneous execution of a specific trading strategy across all grouped algorithms, synchronized to within nanoseconds to mitigate latency arbitrage.
• Mermaid Diagram:

  sequenceDiagram
      participant User
      participant Controller
      participant ZoneHead_Algo as Arbitrage Algorithm
      participant Member_Algo1 as Liquidity Provider
      participant Member_Algo2 as Risk Management
      User->>Controller: Select ZoneHead_Algo as Head
      User->>Controller: Group Member_Algo1 and Member_Algo2
      Controller->>ZoneHead_Algo: Form Group [Head]
      Controller->>Member_Algo1: Form Group [Member of ZoneHead_Algo]
      Controller->>Member_Algo2: Form Group [Member of ZoneHead_Algo]
      Note right of ZoneHead_Algo: All algos sync to PTP Master Clock
      User->>Controller: Execute Trade Strategy
      Controller->>ZoneHead_Algo: EXECUTE at Timestamp T
      ZoneHead_Algo-->>Member_Algo1: EXECUTE at Timestamp T
      ZoneHead_Algo-->>Member_Algo2: EXECUTE at Timestamp T
  

Derivative 2.2: Low-Bandwidth Asynchronous Grouping for Deep-Space Probe Swarms

• Enabling Description: A method for controlling a swarm of deep-space probes ("players") over a high-latency, low-bandwidth network (e.g., Deep Space Network). The controller displays the last known state of each probe. The user forms a group to perform a coordinated scientific measurement. The selection of a "zone group head" and members is queued on the controller. The grouping commands are bundled into a compressed data packet and transmitted. The probes execute the commands asynchronously upon receipt, confirming group formation via a slow return channel. "Synchronization" is not real-time playback but a coordinated execution of a data collection sequence at a future, specified mission time. Each probe uses its local clock, corrected for predicted clock drift, to initiate the sequence at the target time.
• Mermaid Diagram:

  flowchart TD
      subgraph Ground Control
          A[Display Last Known Probe States] --> B{User Selects Group};
          B --> C[Queue Grouping Commands];
          C --> D[Compress and Transmit Packet];
      end
      D -- High Latency Link --> E;
      subgraph Probe Swarm (Deep Space)
          E[Receive & Decompress Packet] --> F{Execute Grouping Command};
          F --> G[Confirm Group Formation];
          G --> H{Schedule Synced Action for Future Time T};
          H --> I[Execute Data Collection];
      end
      G -- Return Link --> J[Update Ground Control State];
  

Axis 3: Cross-Domain Application

Derivative 3.1 (Aerospace): Synchronized Control of Distributed Flight Actuators

• Enabling Description: A flight control system for a large, flexible-wing aircraft or a distributed satellite formation. Each control surface actuator or satellite thruster is a "player." The flight control computer ("controller") groups actuators into functional sets (e.g., "aileron group," "flap group"). Selecting a "zone group head" (e.g., the inboard aileron actuator) and grouping it with others (outboard ailerons) allows for synchronized deflection commands. This ensures that the aerodynamic surfaces move in unison, preventing undesirable structural torsion. The synchronization protocol is implemented over a time-triggered, deterministic bus (e.g., TTP or FlexRay) to guarantee command delivery and execution within strict temporal bounds.
• Mermaid Diagram:

  graph TD
      FCC[Flight Control Computer] -- TTP Bus --> G1{Aileron Group}
      FCC -- TTP Bus --> G2{Flap Group}
      G1 --> A1[Inboard Aileron Actuator - HEAD]
      G1 --> A2[Mid-board Aileron Actuator]
      G1 --> A3[Outboard Aileron Actuator]
      subgraph Command
          FCC -- "Deflect 15 deg" --> A1
          A1 -- "Sync: Deflect 15 deg" --> A2
          A1 -- "Sync: Deflect 15 deg" --> A3
      end
  

Derivative 3.2 (Medical): Coordinated Multi-Drug Infusion System

• Enabling Description: A method for controlling multiple smart infusion pumps ("players") for a patient in an ICU. A central nursing station console ("controller") displays all active pumps for a patient. A clinician can group pumps to administer a multi-drug cocktail that requires synchronized delivery rates or timed boluses. For example, a vasodilator ("zone group head") can be grouped with a vasoconstrictor. When the rate of the vasodilator is adjusted, the system can automatically and synchronously adjust the rate of the vasoconstrictor according to a pre-programmed pharmacological model to maintain stable blood pressure. All actions are time-stamped and logged for medical records.
• Mermaid Diagram:

  sequenceDiagram
      participant Clinician
      participant Controller as Nursing Station
      participant PumpA as Vasodilator (Head)
      participant PumpB as Vasoconstrictor
      Clinician->>Controller: Group PumpA and PumpB
      Controller->>PumpA: Designate as Head
      Controller->>PumpB: Join Group of PumpA
      Clinician->>Controller: Increase PumpA rate by 10%
      Controller->>PumpA: Set Rate = X
      PumpA->>PumpB: Sync: Set Rate = Y (based on model)
      PumpA-->>Controller: Log: Rate set to X
      PumpB-->>Controller: Log: Rate set to Y
  

Axis 4: Integration with Emerging Tech

Derivative 4.1 (AI): Proactive Contextual Grouping with AI

• Enabling Description: An apparatus for controlling players that incorporates an AI engine for proactive group management. The AI engine analyzes real-time data from IoT sensors (e.g., UWB presence tags, microphones analyzing ambient noise), user calendars, and historical usage patterns. Based on this context, it predicts user intent and presents a suggested group configuration on the controller screen. For example, if the AI detects user A has moved from the kitchen to the living room, and it's 7 PM on a weekday (a common music listening time), it will automatically suggest grouping the Kitchen and Living Room players. The user can accept this suggestion with a single tap. The AI's model is trained via federated learning across multiple households to improve its predictive accuracy without compromising individual user privacy.
• Mermaid Diagram:

  graph TD
      subgraph Data Ingestion
          A[IoT Sensor Data]
          B[User Calendar]
          C[Historical Usage]
      end
      A & B & C --> D{AI Prediction Engine};
      D --> E[Generate Suggested Group];
      E --> F{Controller UI};
      F -- User Action --> G{Accept/Reject};
      G -- Accept --> H[Execute Grouping Command];
      G -- Reject --> I[Feedback to AI Model];
      I --> D;
  

Axis 5: The "Inverse" or Failure Mode

Derivative 5.1: Graceful Degradation and Dynamic Head Re-election Protocol

• Enabling Description: A method for maintaining group synchronization in unstable network conditions. Each player in a group constantly monitors its network quality (latency, jitter, packet loss) to the zone group head. If a member player determines its connection quality has fallen below a QoS threshold, it will buffer the audio and attempt to play based on timing prediction. If the head itself has poor network quality or drops from the network, the remaining group members initiate a leader election protocol (e.g., based on the Raft consensus algorithm). The player with the most stable network connection and lowest UUID is elected as the new group head. It resumes the stream from the last known playback position, and the other players re-synchronize to the new head, ensuring minimal interruption.
• Mermaid Diagram:

  stateDiagram-v2
      state "Group Stable" as Stable {
          state "Head: Player A" as HeadA
          state "Member: Player B"
          state "Member: Player C"
      }
      [*] --> Stable
  
      Stable --> Election: Network Failure on Player A
      Election --> NewStable: Player B elected as new Head
      state "Group Stable" as NewStable {
          state "Head: Player B" as HeadB
          state "Member: Player A (rejoining)"
          state "Member: Player C"
      }
      NewStable --> [*]
  

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Part 2: Derivative Works Based on Volume Control

This section explores variations on the methods for controlling the volume of individual and grouped players, as described primarily in independent claims 1, 16, and 38.

Axis 3: Cross-Domain Application

Derivative 8.1 (Theatrical/Live Events): Synchronized Lighting Intensity Control

• Enabling Description: A method for controlling a plurality of DMX- or Art-Net-enabled stage lighting fixtures ("players"). A lighting console ("controller") displays a list of fixtures. A lighting designer can group multiple fixtures (e.g., "front wash," "backlight"). A master intensity fader ("volume meter") is presented for the group. Adjusting this master fader synchronously changes the brightness of all lights in the group. Crucially, if the lights within the group have been pre-set to different relative intensities (e.g., one at 80%, another at 50%), adjusting the master fader maintains this relative difference. For example, moving the master fader down by 20% would set the lights to 64% (80% * 0.8) and 40% (50% * 0.8) respectively, preserving the visual balance of the scene. The group's master level could be represented as the average intensity of the fixtures in the group.
• Mermaid Diagram:

  flowchart TD
      A[Lighting Console UI] --> B{Select 'Front Wash' Group};
      B --> C[Display Group Master Fader];
      C -- User Adjusts Fader by -20% --> D{Calculate Relative Intensity Change};
      subgraph DMX/Art-Net Network
          D --> L1[Light 1: Current 80% -> New 64%];
          D --> L2[Light 2: Current 50% -> New 40%];
          D --> L3[Light 3: Current 80% -> New 64%];
      end
  

Axis 4: Integration with Emerging Tech

Derivative 9.1 (AI): AI-Based Perceptual Volume Balancing

• Enabling Description: An apparatus for controlling player volume that uses an AI model to achieve perceptually uniform loudness across different zones. Each player has a calibrated microphone. During a setup phase, the system plays test tones, and the AI builds an acoustic model of each zone, accounting for room size, reflectivity, and ambient noise. When players are grouped, the AI automatically adjusts the individual player amplifier gains so that the sound pressure level (SPL) at a likely listening position is consistent. The user is presented with a single group volume meter. When this meter is adjusted, the AI dynamically calculates the necessary gain changes for each player to raise or lower the overall volume while maintaining the perceptually balanced soundfield. The "averaged value" shown on the group meter is a normalized perceptual loudness unit (LUFS), not a simple average of amplifier settings.
• Mermaid Diagram:

  sequenceDiagram
      participant User
      participant Controller
      participant AI_Engine
      participant Player_LivingRoom as LR
      participant Player_Kitchen as KIT
      Note over AI_Engine, KIT: AI has pre-built acoustic models for LR and KIT
      User->>Controller: Group LR and KIT
      User->>Controller: Set Group Volume to '50'
      Controller->>AI_Engine: Request perceptual balance for Group at Level 50
      AI_Engine->>LR: Set Amp Gain to 45% (based on model)
      AI_Engine->>KIT: Set Amp Gain to 62% (based on model)
      Note right of KIT: Result is equal SPL in both rooms
  

Axis 5: The "Inverse" or Failure Mode

Derivative 10.1: Emergency Egress Volume/Intensity Override

• Enabling Description: A method for controlling a group of audio players and/or lighting fixtures that is integrated with a building's fire alarm or emergency control system. Upon receiving a signal from the emergency system, the controller enters an override mode. In this mode, all user control is disabled. The audio volume of all players in a group is synchronously set to a pre-determined level to broadcast an evacuation message, while all lighting fixture intensities are synchronously set to 100% to illuminate egress paths. This happens regardless of any pre-existing group or relative volume/intensity settings. The state transition is non-reversible without a specific "all-clear" signal from the emergency system.
• Mermaid Diagram:

  stateDiagram-v2
      NormalOps: Normal Operation
      Emergency: Emergency Override
      NormalOps --> Emergency: Fire Alarm Signal Received
      Emergency --> NormalOps: 'All Clear' Signal Received
  
      state Emergency {
          direction LR
          [*] --> SetAudioVolume
          SetAudioVolume --> SetLightIntensity
          SetLightIntensity --> DisableUserControl
          DisableUserControl --> [*]
      }
  

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Part 3: Combination Prior Art Scenarios

This section describes how the core concepts of US 7,571,014 could be implemented by combining them with well-established, open-source standards, thereby suggesting the obviousness of such an implementation.

Combination 3.1: Group Management via MQTT (Message Queuing Telemetry Transport)

• Enabling Description: A multi-zone audio system where each player is an MQTT client, and the controller is both a client and potentially hosts the MQTT broker.
  • Discovery: Each player, upon startup, publishes its identity (UUID, friendly name, capabilities) to a topic like players/discovery with the retain flag set. The controller subscribes to players/discovery to build its list of available players.
  • Grouping: To create a group, the controller publishes a JSON payload to a command topic, e.g., groups/manage. Payload: {"action": "create", "group_id": "group123", "head_uuid": "player_A_uuid", "members": ["player_B_uuid", "player_C_uuid"]}. All players are subscribed to groups/manage and will parse this message. Player A configures itself as the head, and Players B and C configure themselves as members, pointing to Player A for stream and sync information.
  • Volume Control: To change the group volume, the controller publishes to groups/group123/volume/set. Payload: {"level": 55, "is_relative": true}. The head player (and/or all member players) receives this and adjusts its volume accordingly. Individual player volume is controlled via topics like players/player_B_uuid/volume/set.

Combination 3.2: Synchronization via RTP/RTSP (Real-time Transport Protocol)

• Enabling Description: The system leverages standard streaming protocols for synchronization.
  • The "zone group head" selected by the controller acts as a lightweight RTSP server and RTP media sender. It sources the audio (from a local file, line-in, or internet stream).
  • When other players are added to the group, the controller sends them the RTSP URI of the group head (e.g., rtsp://192.168.1.10:554/stream).
  • The member players act as standard RTSP/RTP clients. They connect to the head, receive the audio stream via RTP, and play it out.
  • Synchronization, a core teaching of the patent, is achieved by leveraging the RTP timestamps embedded in each packet from the head. All member players buffer the incoming stream and use the RTP timestamps, in conjunction with NTP-synchronized local clocks, to schedule the audio rendering, ensuring lock-step playback across the group.

Combination 3.3: Player Discovery and Control via UPnP (Universal Plug and Play)

• Enabling Description: The system is built on the UPnP architecture.
  • Discovery: Each media player device runs a UPnP Device service. It advertises itself on the network using SSDP (Simple Service Discovery Protocol). The controller acts as a UPnP Control Point, listening for SSDP announcements to discover and list all available players.
  • Control & Grouping: In addition to standard UPnP services like AVTransport and RenderingControl, each player exposes a custom, vendor-defined service specified in its device XML file, such as X_Sonos_Group.xml. This service defines custom UPnP Actions like CreateGroup(HeadUUID) and AddToGroup(MemberUUID). The controller calls these actions on the players via SOAP messages to form and manage groups.
  • Volume Control: The RenderingControl service, a standard part of UPnP, is used for volume. Its SetVolume(Master, DesiredVolume) action controls an individual player. For group volume, the controller iterates through all players in a group and calls SetVolume on each, or it could call a custom action like SetGroupVolume on the head player, which would then propagate the command to its members. Maintaining relative volume would be a function handled by the Control Point logic before sending individual SetVolume commands.