Self-propelled tubular apparatus

Abstract

An example peristaltic actuating system can include an elongated body that includes an arrangement of substantially tubular body segments, in which each of the body segments has a radially inner sidewall portion that is elastically deformable in an axial direction and defines a lumen that is coaxial with lumens of the other body segments to define a central body lumen extending longitudinally through the elongated body. The central body lumen can be configured to carry an elongated tubular apparatus therein and/or can itself define a tubular body structure that can carry one or more structures therein. Each of the body segments includes a flexible outer sidewall portion configured to expand radially and provide a radially outward force responsive to axial contraction of the respective body segment and to contract radially responsive to axial elongation of the respective body segment.

1 . An apparatus comprising:
 a plurality of axially spaced apart rings defining a radially inner surface that defines a hollow central lumen extending longitudinally through the apparatus;   respective actuators coupled to at least some of the rings outside of the central lumen; and   an elongated expandable tubular structure extending over the rings and the actuators, in which the actuators are adapted to change a span and/or diameter of the expandable tubular structure at respective locations along the length of the expandable tubular structure, whereby peristaltic movement of the apparatus is provided.   
     
     
         2 . The apparatus of  claim 1 , wherein an adjacent pair of the rings are spaced apart from each other by an axial distance, and at least one of the actuators is configured to change the axial distance between the adjacent pair of the rings. 
     
     
         3 . The apparatus of  claim 1 , further comprising an outer sheath over the expandable tubular structure, in which the outer sheath is pliant and conforming to an outer surface of the expandable tubular structure. 
     
     
         4 . The apparatus of  claim 1 ,
 wherein the radially inner surface of at least some of the rings is one of adapted to support an elongated flexible structure within the central lumen such that the at least some of the rings are configured to slide along and/or attach to an outer surface of the elongated flexible structure, or   wherein the apparatus includes the elongated flexible structure, in which the elongated flexible structure extends longitudinally through at least a substantial portion of the central lumen, and the at least some of the rings are configured to slide along and/or attach to an outer surface of the elongated flexible structure.   
     
     
         5 . The apparatus of  claim 1 , wherein the elongated expandable tubular structure defines an elongated tubular body of the apparatus that extends longitudinally between a proximal end and a distal end of the apparatus, and the apparatus further comprises:
 a tip at the distal end, in which the rings and expandable structure are proximally located from the tip at spaced apart locations along the length of the body.   
     
     
         6 . The apparatus of  claim 5 , wherein the tip comprises a tool adapted to drill, dig, bore, and/or pierce through a medium to facilitate the peristaltic movement of the apparatus through the medium. 
     
     
         7 . The apparatus of  claim 5 , wherein the apparatus further comprises:
 an elongated flexible tubular structure extending longitudinally through at least a substantial portion of the central lumen, in which at least one cable or wire is within the elongated flexible tubular structure, and at least some of the rings are configured to slide along and/or attach to an outer surface of the elongated flexible tubular structure based on activation of the actuators to cause the peristaltic movement of the apparatus along with the elongated flexible tubular structure therein.   
     
     
         8 . The apparatus of  claim 5 , wherein the body comprises:
 an arrangement of body segments, in which each of the body segments has a cylindrical sidewall portion that is extensible in an axial direction and defines a respective lumen that is coaxial with lumens of the other body segments to define the central lumen through elongated tubular body of the apparatus, each of the body segments includes a flexible sidewall portion configured to expand radially and provide a radially outward force responsive to axial contraction of the respective body segment and to contract radially responsive to axial elongation of the respective body segment, at least one of the respective actuators is coupled to at least one respective body segment and configured to cause at least one of the axial contraction or the axial elongation of the at least one respective body segment based on a control signal.   
     
     
         9 . The apparatus of  claim 8 , wherein at least some of the respective actuators comprise:
 an electric motor having an input;   a length of a flexible connecting element coupled between the electric motor and an end portion of a respective body segment, in which the electric motor is configured to change the length of the connecting element and thereby cause a corresponding change in an axial length of the respective body segment; and   a controller having an output coupled to the input of the electric motor and configured to provide the control signal to the input of the electric motor.   
     
     
         10 . The apparatus of  claim 8 , further comprising:
 a flexible membrane spaced radially outwardly from and surrounding the flexible sidewall portion of at least one of respective body segment, in which the flexible membrane has proximal and distal end portions coupled to proximal and distal end rings of the at least one of respective body segment, a space between the flexible membrane and the flexible sidewall portion of the at least one of respective body segment defines at least one fluidic chamber.   
     
     
         11 . The apparatus of  claim 10 , wherein the at least one fluidic chamber is a first fluidic chamber, and the apparatus further comprises:
 a second fluidic chamber between the first fluidic chamber and a portion of the central lumen coextensive with the respective body segment; and   a source of pressurized fluid in fluid communication with the second fluidic chamber of at least the respective body segment;   a valve coupled between the source and the respective body segment; and   a controller coupled to the valve and configured to actuate the valve to control pressure within the second fluidic chamber and thereby change an axial length of the respective body segment.   
     
     
         12 . A peristaltic actuating system, comprising:
 an elongated body comprising a plurality of body segments arranged along a length of the elongated body, in which a central lumen extends longitudinally through the plurality of body segments of the elongated body, the central lumen defines an inner periphery that is configured to hold and/or carry an elongated tubular apparatus, and at least some of the body segments comprise:   a plurality of substantially rigid annular rings, in which the rings are axially spaced apart along a length of a respective body segment between a proximal end ring and a distal end ring;   an arrangement of flexible connecting elements, in which each connecting element extends between an adjacent pair of the rings and is configured to enable relative axial movement between the adjacent pair of rings, and a radially inner surface of the rings and connecting elements defines a portion of the central lumen associated with the respective body segment; and   a flexible membrane spaced radially outwardly from and surrounding the rings and the connecting elements and having proximal and distal end portions coupled to the proximal and distal end rings, respectively, in which a space between the flexible membrane and the rings and connecting elements of the respective body segment defines one or more fluidic chambers thereof.   
     
     
         13 . The system of  claim 12 , wherein the elongated tubular apparatus comprises a pipe and/or an electrical conduit. 
     
     
         14 . The system of  claim 12 , further comprising:
 means for modifying an axial length of a subset of the body segments to cause a corresponding radial expansion or contraction of the flexible membrane of the subset of the body segments and provide peristaltic motion of a portion of the elongated body.   
     
     
         15 . The system of  claim 12 , further comprising:
 an electric motor; and   a length of a flexible connecting element coupled between the electric motor and an end portion of a respective body segment, in which the electric motor is configured to change the length of the connecting element and thereby cause a corresponding change in an axial length of the respective body segment.   
     
     
         16 . The system of  claim 15 ,
 wherein the electric motor comprises a plurality of electric motors, in which each of the electric motors is each of the electric motors is coupled at one of the ends of a respective one of the body segments, and   where the connecting element comprises a plurality of lengths of connecting elements, in which each of the connecting elements is coupled between a given electric motor and an opposing end of a respective body segment to which the given electric motor is coupled.   
     
     
         17 . The system of  claim 15 ,
 wherein the electric motor is configured to apply a motive force in a first direction to reduce the axial length of the respective body segment and to apply a motive force in a second direction, which is opposite the first direction, to increase the length of the respective connecting element, and   wherein the connecting elements are configured to mechanically bias the rings away from each other to increase the axial length of the respective body segment in an absence of an applied force.   
     
     
         18 . The system of  claim 12 , wherein the one or more fluidic chambers is a first fluidic chamber, and each of the at least some of the body segments further comprises:
 a second fluidic chamber between the first fluidic chamber and a portion of the central lumen coextensive with the respective body segment; and   a source of pressurized fluid in fluid communication with the second fluidic chamber of at least the respective body segment;   a valve coupled between the source and the respective body segment; and   a controller coupled to the valve and configured to actuate the valve to control pressure within the second fluidic chamber and thereby change an axial length of the respective body segment.   
     
     
         19 . The system of  claim 18 , wherein the valve comprises an electromechanically operated valve,
 wherein the controller is configured to control the valve in a first state to increase pressure within the second fluidic chamber and cause an increase in the axial length of the respective body segment, and to control the valve in a second state to decrease pressure within the second fluidic chamber and cause a reduction in the axial length of the respective body segment, and   wherein the second fluidic chamber includes a radially outer cylindrical sidewall portion, a radially inner cylindrical sidewall portion opposite the outer cylindrical sidewall portion, and axially spaced apart end portions extending between the outer cylindrical sidewall portion and the inner cylindrical sidewall portion.   
     
     
         20 . A locomotion system, comprising:
 an elongated body having a central body lumen extending longitudinally through the elongated body, the central body lumen defines or is configured to carry an elongated tubular apparatus therein;   a first body segment at a first location along the elongated body; and   a second body segment at a second location along the elongated body that is spaced axially apart from the first body segment,   wherein each of the first and second body segments is configured to independently actuate radially and/or axially with respect to the elongated body and the other body segment to provide peristaltic motion of the body segments and corresponding longitudinal motion of the elongated body and respective segments through a surrounding media.