| Popis: |
Fully insertable laparoscopic cameras represent a promising future of minimally invasive surgery. The most characteristic technology adopted on these devices is transabdominal anchoring and actuation based on magnetic coupling. However, few have paid adequate attention to the safety concerns. As the camera is anchored against the interior abdominal wall without any force feedback, the patient is being exposed to a high risk of getting injured by inappropriate stress on the tissue. We have recovered the camera-tissue interaction force via a non-invasive approach in our previous work. Aiming to access the stress distribution, this paper presents a viscoelastic camera-tissue interaction model, which establishes explicit relations between the contact force and the stress distribution on the tissue. For the first time, a geometric constraint between the contact angle and the tissue indentation is introduced, which helps make the multivariable model solvable. Ex-vivo experiments on porcine abdomen tissue facilitated by non-invasive force measurement validate effectiveness of the model. This work lays foundation for improving control and surgical safety of using a magnetic actuated insertable laparoscopic surgical camera. |
