Effects of Rotational Motion in Robotic Needle Insertion

Area of Science:

• Robotics
• Biomedical Engineering
• Materials Science

Background:

• Robotic needle insertion is crucial for medical procedures like sampling and injections.
• Understanding tissue mechanics during robotic interventions is essential for safety and efficacy.

Purpose of the Study:

• To investigate the impact of angular velocity on soft tissue insertion forces.
• To analyze the force-displacement relationship during robotic needle insertion with varying rotational speeds.

Main Methods:

• Utilized camel liver as a non-homogenous soft tissue sample.
• Performed needle insertion experiments at different linear velocities (5, 50, 200 mm/min) with and without rotational motion (50, 150, 300 rpm).
• Measured insertion forces and friction using a load-cell and a custom fixture.

Main Results:

• Force-displacement graphs demonstrated significant differences between insertion with and without rotation.
• The study provides a mechanism for generating rotational motion during needle insertion.
• Friction forces were analyzed at deeper penetration levels.

Conclusions:

• Angular velocity significantly affects the mechanics of robotic needle insertion in soft tissues.
• While rotational motion alters insertion forces, tissue damage like bleeding and micro-structural disorganization remains a challenge.