The output of the system over 100 cycles is then collected, and the standard error over 100 cycles is calculated. The standard error of the system is 19 pixels. The internal error of this system will affect our tracking experiment, which cannot be eliminated by the designed controller.

Results

Experiments on tracking static instruments

To evaluate the autonomous laparoscopic control method to adjust the view of a continuum laparoscope, we perform the experiments on static surgical instruments. We conduct repeat trials for different surgical instruments. Only the initial position of the surgical instrument is different. As shown in Figure 2(a), the black point represents the initial position of the tracking keypoint on the surgical instrument. The scatters mean the position of the tracking point relative to the center of the FOV at each step. Figure 2(b) shows the distance between the tracking point and the FOV center of the laparoscope. When the continuum laparoscopy was controlled to automatically adjust the FOV based on visual feedback, it needs approximately 25 steps to approach the center of the FOV. This is consistent with our verification in the simulation environment. After 25 steps, the continuum laparoscope remains largely stationary, indicating that our approach provides a stable FOV after the tracking purpose is reached. The tracking error is approximately 39.1 pixels when the system is stable.