VR Avatar Physics Engine Using Ghost Hands and Force Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional virtual reality (VR) and avatar animation systems face limitations in providing immersive and natural movements, particularly in handling full-body interactions and locomotion, as they often require extensive sensor data and struggle with physical realism and natural motion capture.
Innovation Solution
An interactive avatar display system that uses a physics engine to compute and apply forces and torques to avatar body parts based on sensor inputs, allowing for real-time animation and interaction with virtual environments, while also employing 'ghost hands' to reconcile discrepancies between real and virtual hand positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional VR systems use extensive sensor data for full-body tracking, then measurement precision of user movements is improved, but device complexity and cost increase significantly
Solution Approach 1:
The system segments the avatar into multiple body parts (head, torso, arms, legs) and applies different tracking methods to each segment. The head receives full 6-DOF tracking while other body parts use simplified tracking models, reducing the overall sensor requirements while maintaining natural movement appearance.
Solution Approach 2:
The patent introduces ghost hands as intermediary elements that mediate between the user's actual hand position (from limited sensors) and the virtual avatar's hand position. These ghost hands reconcile discrepancies and provide natural-looking hand movements without requiring direct sensor input for each hand.
2Reliability
If the system uses physics engine with multiple force arrays, then natural motion and physical realism are improved, but computational power and processing time increase
Solution Approach 1:
The physics simulation is segmented into multiple independent force arrays (balance forces, locomotion forces, interaction forces) that can be computed separately and then combined. This modular approach reduces computational complexity compared to solving a single large physics system.
Solution Approach 2:
The system applies physics forces selectively to only those body parts that need physical realism (such as feet for balance, hands for interaction) rather than applying full physics simulation to the entire avatar. This partial application reduces computational load while maintaining natural motion where it matters most.
3Adaptability or versatility
If the avatar model includes complete full-body representation, then adaptability and immersion are improved, but the difficulty of detecting and measuring all body movements increases
Solution Approach 1:
The full-body avatar is segmented into critical tracking zones (head, hands, feet) and less critical regions. Sensors are strategically placed only at critical zones, and the physics engine infers movements of non-tracked body parts based on rigid body constraints and joint models, reducing tracking difficulty while maintaining complete avatar representation.
Solution Approach 2:
The system creates a simplified copy model of the avatar's body structure with defined joint constraints and rigid body relationships. This copy model allows the physics engine to predict and generate realistic movements for body parts that are not directly tracked by sensors, based on the movements of tracked parts.
Data Source
AI summary
An interactive avatar display system provides a computer-generated view of a virtual space including an avatar that moves in the virtual space in response to movements of the user that are sensed by sensors. The number of sensed movements is less than the number of degrees of freedom of avatar movement. The interactive avatar display system computes an array of accelerations to apply to movable body parts of the avatar and computes the array of accelerations by solving equations of motions from masses of the movable body parts and an array of forces computed from an array of inverse dynamics force values for the movable body parts and one or both of an array of balance control force values or an array of locomotion control force values, taking into account a set of constraints for the avatar, and possible also environmental objects in the virtual space.