Vision-based variable impedance control with oscillation observer for respiratory motion compensation during robotic needle insertion: a preliminary test

A robotic puncture system with optical and mechanical feedback under respiratory motion

Puncture robot can improve the accuracy and efficiency of puncture surgery, such as thoracoabdominal and liver puncture. However, as soft tissue is deformed and shifted under respiratory motion and during the puncture process, the needle is pulled, resulting in the needle's bending and deformation, which increases the risks and sufferings of the patient, a robotic puncture system with optical and mechanical feedback is necessary. Therefore, this paper proposes a multi-information sensing 'guide-clamp' end effector for puncture surgery to accurately detect the posture and force on the puncture needle in real time. And gravity bias method with trajectory planning and the compensational controlling model are also proposed to offset the interference of self-weight and achieve zero force following. This system is evaluated by the experiments of robot controlling and human tissue simulation and the results prove the excellent robustness of the system, which meet the clinical requirement.

Impedance and admittance control for respiratory-motion compensation during robotic needle insertion - a preliminary test

BACKGROUND

Many robotic needle-biopsy systems have been developed to enhance the accuracy of needle-biopsy intervention. These systems can reduce the intervention time and the radiation exposure of clinicians. However, respiratory-motion compensation is needed to ensure the accuracy and efficiency of needle biopsy intervention.

METHODS

Human respiratory-motion data were acquired using three inertial measurement units (IMUs), and respiratory motion was simulated using the Stewart-Gough platform. Robotic needle intervention was performed using impedance and admittance control algorithms for respiratory-motion compensation using the Stewart-Gough platform and a gelatin phantom.

RESULTS

The impedance and admittance control algorithms can be used to compensate for respiratory motion during robotic needle insertion. The admittance control algorithm exhibits better performance than the impedance control algorithm.

CONCLUSIONS

The impedance and admittance control algorithms can be applied for respiratory-motion compensation during robotic needle insertion. However, further study is needed for them to become clinically feasible.