Willow 4 DaVinci: The Physics of Intelligence

Willow 4 DaVinci: The Physics of Intelligence

Welcome to the Realtime World Model for Human Motion.

You are not just using video analysis software. You are stepping into a persistent, AI-driven training environment. Willow 4 DaVinci is a platform that doesn't just "see" video; it reconstructs physical reality. By fusing computer vision with Newtonian physics, we transform standard video into a deep, queryable model of the kinetic world.

This guide serves two purposes: to orient you within our "Physics-First" ecosystem and to provide a practical manual for operating the interface. Whether you are an athlete optimizing performance, an engineer exploring our architecture, or a coach looking for the truth behind the motion, this is your starting point.

1. The Architecture: World Models & The Hierarchy of Truth

What is a World Model?

Traditional AI (like Large Language Models) predicts the next word in a sentence. A World Model predicts the next state of a physical system. Willow is built to understand object permanence, gravity, velocity, and biomechanical constraints. It doesn't hallucinate movement; it calculates it based on the rigid laws of physics.

The "Da Vinci" Engine: Physics as the Ground Truth

At the core of our platform lies the Da Vinci Engine. Unlike systems that rely purely on visual tracking (which can be fooled by motion blur or lighting), Da Vinci uses a hybrid approach. It maps the human skeleton in 3D space and then applies a physics layer to calculate the movement of implements (bats, clubs, balls) as extensions of the biomechanical system. This allows us to derive data that is visibly imperceptible.

The Hierarchy of Truth: Fact vs. Estimation

To ensure reliability, our system operates on a strict strict data-sourcing protocol:

  • Tier 1 (The Ground Truth): Mathematical derivatives calculated by the physics engine (Velocity, Acceleration, Power). These are treated as immutable facts.
  • Tier 2 (Spatial Reality): 3D World Coordinates derived from multi-point pose estimation and calibrated to real-world units.
  • Tier 3 (Visual Context): AI interpretation of the environment, sport, and scenario.

2. Interface Guide: Operating the Platform

While the backend is complex, the user experience is designed for speed and simplicity.

The Dashboard & "My Tools"

Access your command center by logging in and clicking "My Tools" in the main navigation. This is where your digital twin resides.

Uploading & Ingestion

  1. Select "Upload Video": The system accepts raw video files. No editing is required; the AI will autonomously segment the footage into distinct athletic actions.
  2. Processing Pipeline: Upon upload, the video enters our serverless event-driven pipeline. It is simultaneously processed for computer vision, physics calculation, and biomechanical sequencing.
  3. Notification: You can track progress in the "My Analyses" tab. The system creates a persistent record for every session.

Understanding the Data Dossier

We do not just give you a score; we generate a Data Dossier. This is a comprehensive JSON-structured file containing every calculated metric, every identified mechanical flaw, and the AI's complete reasoning chain. It serves as the "Long-Term Memory" for the AI Coach.

3. Data Acquisition: Recording for the Machine

The quality of the World Model's output depends on the fidelity of the input data. Treat your camera as a sensor.

Sensor Hygiene: Frame Rates & Shutter Speed

  • High Frequency (60fps+): Athletic motion is fast. Higher frame rates allow the physics engine to calculate derivatives (velocity/acceleration) with greater precision.
  • Resolution (1080p/4K): Higher pixel density improves the accuracy of the 3D skeletal mapping.
  • Stability: A stable sensor (tripod) allows for more accurate background subtraction and depth calibration.

Perspective Awareness: How the AI Sees Depth

The system uses advanced homography and perspective correction algorithms. For single-camera setups, orthogonal views (directly from the side or front) provide the cleanest data for the 2D-to-3D conversion pipeline.

Pro Mode: Multi-Sensor Fusion

For the ultimate fidelity, "Pro Mode" allows you to upload synchronized angles of the same event. The system fuses these inputs to construct a true stereoscopic 3D model of the athlete, eliminating perspective correction entirely.

4. The Metrics Engine: Quantifying Reality

The Da Vinci Engine outputs hundreds of data points. We categorize them into six biomechanical domains.

I. Implement Kinetics (The Tool)

Focuses on the external object being manipulated (Bat, Club, Ball).

  • Peak Implement Speed: Maximum velocity achieved by the sweet spot.
  • Speed at Impact: Velocity at the precise moment of contact/release.
  • Peak Acceleration: The rate of velocity change (Explosiveness).
  • Power Output (kW/HP): The rate of energy transfer from the kinetic chain to the tool.
  • Time to Impact: Duration from movement initiation to contact (Efficiency).
  • Attack Angle & Plane: The 3D vector path of the implement through space.

II. Global Body Dynamics

Analysis of the athlete's Center of Mass (CoM) and stability.

  • CoM Displacement (X/Y/Z): Tracking the body's core movement in 3D space.
  • Postural Sway & Thrust: Quantifying stability and balance efficiency.
  • Dynamic Balance Index: A composite score of stability under load.

III. Segmental Kinematics

The rotational velocities of individual body segments.

  • Pelvis & Torso Rotation: Peak velocities and accelerations of the core engines.
  • Arm Elevation & Velocity: Tracking the distal segments.

IV. Kinematic Sequencing (The "Whip")

The "Holy Grail" of biomechanics: measuring the timing of energy transfer.

  • Kinematic Sequence Graph: Visualizing the order of peak velocities (Pelvis → Torso → Arm → Tool).
  • Hip-Shoulder Separation ("X-Factor"): The elastic stretch created between the core segments.
  • Gain Ratios: Calculating the efficiency of energy amplification from one segment to the next.

V. Joint-Level Mechanics

Granular analysis of joint angles for technique and safety.

  • Shoulder Rotation (Internal/External): Critical for throwing sports.
  • Elbow Flexion/Extension: Extension velocities and structural loading.
  • Knee Valgus/Varus (Estimated): Identifying injury risk factors in the lower body.

VI. Ground Reaction (Estimated)

Using inverse dynamics to estimate how the athlete interacts with the earth.

  • Vertical & Horizontal Force: Estimates of braking and propulsive forces.
  • Rate of Force Development (RFD): How quickly force is applied to the ground.

5. Interactive Intelligence: The AI Coach

This is not a chatbot. It is a context-aware expert system that has "watched" your video and memorized your biomechanical data.

Beyond Chatbots: Persistent Context

Because the AI references your specific Data Dossier, it understands the history of your development. It doesn't just answer generic sports questions; it answers questions about your specific motion in the uploaded video.

Querying the Model

You can interrogate the physics engine directly using natural language:

  • "Why did I lose power on the third swing?"
  • "Show me the relationship between my hip separation and bat speed."
  • "Compare my kinematic sequence to the ideal pro model."

Adaptive Expertise Levels

The AI scales its complexity based on the user. It can explain mechanics to a Little Leaguer ("Use your legs more") or a PhD Biomechanist ("Your peak pelvic angular velocity is delayed by 40ms relative to foot plant").

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