Facial Rig Generation via Muscle Model Training

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for animating computer-generated characters struggle to accurately replicate the complex facial expressions and movements of live actors, as they require tedious specification of numerous facial muscles and their attachments, which can vary significantly between individuals, making it impractical to create realistic and diverse animations.

Innovation Solution

A computer-implemented method using facial scans and muscle models to train an AI system, which generates a facial puppet that can express a wide range of plausible facial expressions by deriving strain vector values from multiple live actors, allowing for the creation of animated images that correspond to realistic actor performances.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If detailed specification of numerous facial muscles and their attachments is performed, then animation precision is improved, but device complexity and time consumption increase significantly

Engineering Contradiction:
Improveanimation precisionVSAvoidfacial muscle specification complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent creates a digital copy of the actor's face through 3D scanning, generating a virtual replica that can be manipulated without requiring detailed manual specification of each muscle. This digital twin approach allows precise animation through automated transformation of the scanned geometry rather than manual muscle-by-muscle modeling.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent replaces manual mechanical specification of muscle attachments with an automated AI-based system that processes 3D scan data and generates muscle models automatically. The system substitutes human expertise in manually defining muscle geometry with computational algorithms that infer muscle structures from surface scans and anatomical knowledge.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Manufacturing precision

If manual specification of facial muscles is performed, then animation accuracy is improved, but loss of time increases

Engineering Contradiction:
Improveanimation accuracyVSAvoidtime consumption
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary 3D scanning of the actor's face to capture geometric data before animation production. This pre-processing step creates a reusable digital model that can be rapidly transformed into various expressions without requiring time-consuming manual muscle specification during the animation process itself.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent replaces time-consuming manual muscle specification with automated computational processes that generate muscle models and transformations algorithmically. The system automatically processes scan data, infers muscle geometries, and generates animation rigs without human intervention in the detailed modeling phase.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of manufacture

If generic facial models are used, then ease of manufacture is improved, but measurement precision and anatomical accuracy deteriorate

Engineering Contradiction:
Improvemodel creation easeVSAvoidanatomical accuracy
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

The patent applies local quality by customizing the facial model to match the specific anatomical characteristics of each actor through individual 3D scanning. Rather than using a generic model, the system captures and preserves actor-specific features such as unique muscle attachments, facial contours, and geometric variations, creating a tailored model for each performer.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent utilizes parameter changes by transforming the scanned facial geometry through non-rigid deformation algorithms that preserve anatomical plausibility while adapting to different expressions. The system maintains anatomical accuracy by constraining transformations within biologically plausible ranges derived from the scanned muscle models.

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If AI training with multiple actors is performed, then adaptability and versatility are improved, but device complexity and computational resources increase

Engineering Contradiction:
Improvefacial expression rangeVSAvoidAI system complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent creates a universal facial animation system that can handle multiple actors and expression types through a single AI-trained model. The system is designed to process scans from different actors, learn their specific anatomical variations, and generate appropriate muscle models and animations automatically, making it multi-functional across diverse casting scenarios.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent creates digital copies of multiple actors' faces through 3D scanning and trains the AI system on these copies to learn general facial anatomy and expression patterns. This approach allows the system to handle new actors by scanning and training them similarly, providing versatility without requiring completely different systems for each actor.

Inventive Principle:
Principle #26Copying

Data Source

PatentUS11715247B1Generating a facial rig for use in animating a computer-generated character based on facial scans and muscle models of multiple live actors
Publication Date: 2023.08.01 UNITY TECH SF
  • US11715247B1 patent drawing
  • US11715247B1 patent drawing
  • US11715247B1 patent drawing

AI summary

An animation system wherein scanned facial expressions are processed to form muscle models based on live actors combines muscle models over a plurality of live actors to form a facial rig usable for generating expressions based on specification of a strain vector and a control vector of a muscle model for varying characters corresponding to live actors.