Steerable endoscope with motion alignment
A steerable endoscope is provided with active steering control. An endoscope includes a flexible tubular body with first and second articulating segments, and a camera. In an embodiment, the endoscope includes an orientation sensor. A controller for the endoscope performs an automated analysis of an alignment between the motion axis of the endoscope and the viewing axis of the camera, and actively steers the endoscope to improve the alignment.
1. A method for computer-aided steering of an endoscope, comprising:
receiving, via a touch screen display, a user input to move a viewing axis of an endoscope, the endoscope comprising:
a first articulating segment positioned at a distal end of the endoscope;
a second independently articulating segment located at the distal end of the endoscope and coupled to a proximal end of the first articulating segment;
a camera, positioned at the distal end of the first articulating segment, having a field of view along the viewing axis; and
an orientation sensor positioned at the distal end of the endoscope;
in response to the user input, articulating the first articulating segment of the endoscope to move the viewing axis;
receiving from the orientation sensor a motion signal indicating movement of the endoscope along a motion axis;
comparing, at a processing chip, the motion axis with the viewing axis, wherein comparing the motion axis with the viewing axis comprises generating an alignment metric indicating a degree of alignment between the camera axis and the motion axis; and
generating a steering signal that controls articulation of the first and second articulating segments to reduce a difference between the motion axis and the viewing axis.
2. The method of claim 1 , further comprising identifying an object near a center of the field of view and tracking movement of the object within the field of view, and wherein the alignment metric comprises a deviation of the object from the center of the field of view.
3. The method of claim 1 , wherein the alignment metric comprises a degree of spread of pixels moving in the field of view.
4. The method of claim 1 , wherein the alignment metric comprises a degree of convergence or divergence of optical flow lines in the field of view.
5. The method of claim 1 , wherein the alignment metric comprises a proximity of a vanishing point in the field of view with a center of the field of view.
6. The method of claim 1 , comprising articulating the first articulating segment, the second articulating segment, or a combination thereof in response to the steering signal.
7. The method of claim 6 , comprising articulating the second articulating segment and the first articulating segment in opposing directions.
8. The method of claim 1 , wherein the second articulating segment has a length longer than the first articulating segment.
9. The method of claim 8 , wherein the first articulating segment has a length of about 20-40 mm and the second articulating segment has a length of about 30-50 mm.
10. The method of claim 1 , wherein the steering signal is generated during forward motion of the endoscope.
11. The method of claim 1 , wherein the user input comprises a direction of the viewing axis and translation of the endoscope forward or rearward.
12. The method of claim 1 , wherein the generated steering signal causes the viewing axis to be positioned in the middle of a passage and pointed in the direction of forward motion down the passage.
13. The method of claim 1 , further steering signal causes the viewing axis to be maintained in a desired orientation during motion of the endoscope and navigation within the passageway.