A steerable endoscope has an elongated body with a selectively steerable distal
portion and an automatically controlled proximal portion. The endoscope body is
inserted into a patient and the selectively steerable distal portion is used to
select a desired path within the patient's body. When the endoscope body is advanced,
an electronic motion controller operates the automatically controlled proximal
portion to assume the selected curve of the selectively steerable distal portion.
Another desired path is selected with the selectively steerable distal portion
and the endoscope body is advanced again. As the endoscope body is further advanced,
the selected curves propagate proximally along the endoscope body, and when the
endoscope body is withdrawn proximally, the selected curves propagate distally
along the endoscope body. This creates a serpentine motion in the endoscope body
that allows it to negotiate tortuous curves along a desired path through, around,
and between organs within the body.