Adaptive 6-DoF Haptic Contact Stiffness Using the Gauss Map

Area of Science:

• Robotics
• Computer Graphics
• Haptics

Background:

• Penalty-based methods are common for haptic rendering contact resolution.
• Simultaneous distributed contacts in complex scenarios cause unpredictable stiffness variations and stability issues.
• Existing solutions like implicit integration or global stiffness scaling lead to large penetrations or ignored small contacts.

Purpose of the Study:

• To develop a novel adaptive stiffness method for stable and accurate haptic rendering.
• To address stability problems and minimize penetration in complex, distributed contact scenarios.
• To improve haptic simulation for large-scale, multi-directional, and six-degrees-of-freedom (6-DoF) contact.

Main Methods:

• Proposed an adaptive stiffness method utilizing the Gauss map of normal distribution.
• Implemented virtual coupling saturation to control penetration depth.
• Applied the method to penalty-based formulations for rigid and reduced deformable objects.

Main Results:

• Achieved spatially uniform and controllable stiffness across all contact directions.
• Successfully maintained shallow penetrations while ensuring simulation stability.
• Demonstrated effectiveness in challenging 6-DoF haptic rendering scenarios, including virtual assembly of car engines and landing gear.

Conclusions:

• The adaptive stiffness method enhances stability and accuracy in penalty-based haptic rendering.
• It effectively manages complex distributed contacts, even in 6-DoF scenarios.
• The approach is fast and applicable to various rigid and reduced deformable object simulations.