Difference of perceiving object softness during palpation through single-node and multi-node contacts.

Area of Science:

• Medical Simulation
• Haptics and Virtual Reality
• Biomedical Engineering

Background:

• Virtual Reality (VR) simulators are increasingly used for medical training.
• Current VR systems often use single-node contact for object interaction, which is insufficient for simulating palpation.
• Palpation requires multi-node contact to accurately represent the interaction with soft tissues.

Purpose of the Study:

• To investigate the difference in perceived softness of virtual breast phantoms using single-node versus multi-node contact in a VR simulation.
• To determine if visual and haptic stimuli affect the perception of softness in VR palpation.

Main Methods:

• A co-located VR setup was used, aligning visual and haptic feedback.
• Fifteen participants evaluated virtual breast phantoms under conditions with and without visual/haptic stimuli.
• Participants compared phantoms palpated via single-node and multi-node contacts with varying force arrays.

Main Results:

• Virtual breast phantoms palpated with single-node contact were consistently perceived as harder than those with multi-node contact when visual stimuli were present.
• The difference in perceived softness was significant, indicating an impact of contact method on tactile feedback realism.
• Perception varied based on the availability of combined visual and haptic stimuli.

Conclusions:

• Single-node contact in VR palpation significantly alters the perception of softness, making virtual objects feel harder.
• Developing realistic VR palpation training requires advanced multi-node contact simulation with accurate force feedback.
• Current VR palpation training systems may face limitations due to inadequate contact simulation methods.