Patent Description:
At least some machines, such as rotary machines, are inspected periodically to determine if components of the machines need repair and/or replacement. However, some components of the machine may be difficult to access and inspect without disassembly of the machine. For example, some components are positioned within a cavity of the machine and are difficult to access from an exterior of the cavity. Accordingly, insertion apparatus such as borescopes are commonly used to inspect and repair components within the cavity of the machine. However, the machine can include obstructions or turns in the cavity that are difficult for at least some known insertion apparatus to navigate around. Moreover, at least some known insertion apparatus experience forces such as gravity that cause the insertion apparatus to deform or shift out of a desired position as the insertion apparatus travel and operate within the cavity. However, at least some known insertion apparatus are not capable of flexing to navigate around objects and maintaining a desired shape when experiencing forces on the insertion apparatus.

At least some known insertion apparatus are connected to actuators located on an exterior of the cavity and configured to steer the insertion apparatus around obstacles and position the insertion apparatus at desired locations within the cavity. For example, the actuators are connected to the insertion apparatus by cables or rods that transmit forces to the insertion apparatus for positioning the insertion apparatus within the cavity. However, at least some known actuators limit the range of movement of the insertion apparatus. Moreover, at least some known actuators are not able to actuate every section of the insertion apparatus because the connectors extend along multiple sections of the insertion apparatus and the actuators are not able to transmit forces to individual sections of the insertion apparatus necessary to move the sections individually. In addition, at least some known actuators increase the size of the insertion apparatus and make it difficult for the insertion apparatus to fit within the cavity. <CIT> relates to a flexible tool comprising stiffening means switchable in use from a first state of relatively low stiffness to a second state of relatively high stiffness, and subsequently switchable from the second state back to the first state.

Accordingly, it is desirable to provide an insertion apparatus including a rigidizable and actuated body that is configured to inspect or repair components positioned within a cavity of a machine.

In one aspect, the invention concerns an insertion apparatus according to claim <NUM>.

In another aspect, the invention concerns a system according to claim <NUM>.

In yet another aspect not forming part of the claimed invention, a method of inspecting a cavity of a machine is provided. The method includes inserting an insertion end of an insertion apparatus into the cavity. The insertion apparatus includes a body extending from the insertion end to a steering end and sized to fit within the cavity. The body includes a plurality of members flexibly coupled together and individually actuated by a plurality of actuator strands. Each member of the plurality of members has a first configuration and a second configuration. The method also includes moving the insertion apparatus through the cavity with at least one member of the plurality of members in the first configuration. At least a portion of the body is flexible and has a first stiffness that facilitates travel of the body through the cavity when the at least one member of the plurality of members is in the first configuration. The method further includes changing a shape of the body by actuating at least one member of the plurality of members using the plurality of actuator strands and switching the at least one member of the plurality of members from the first configuration to the second configuration. The at least a portion of the body is rigid and has a second stiffness greater than the first stiffness when the at least one member of the plurality of members is in the second configuration.

As used herein, the term "rigid" refers to an object that is unable to bend or deform.

Embodiments described herein provide an insertion apparatus including a rigidizable body. The rigidizable body extends from an insertion end to a steering end and includes a plurality of members flexibly coupled together. In some embodiments, at least one maintenance device is coupled to the insertion end of the body. Each member has a first configuration in which the member has a first stiffness and a second configuration in which the member has a second stiffness greater than the first stiffness. For example, in some embodiments, each member includes a phase change material. The state of the phase change material is regulated to provide a desired stiffness for the each member. The plurality of members are individually switched between the first configuration and the second configuration to provide a desired stiffness or flexibility to selected sections of the rigidizable body. For example, at least a portion of the body is flexible to facilitate travel of the body through the cavity when at least one of the members is in the first configuration and is rigid to maintain a selected shape of the body when the at least one member is in the second configuration. Accordingly, the insertion apparatus is able to travel through locations in the cavity that require the insertion apparatus to bend or be more flexible than at least some known insertion apparatus. Also, the rigidizable body of the insertion apparatus is able to maintain a desired shape when experiencing environmental forces. Moreover, the rigid configuration of the body enables the insertion apparatus to perform maintenance operations at locations within the cavity using the maintenance device.

In addition, the insertion apparatus includes a plurality of actuator strands coupled to the members and configured to individually actuate the members. The actuator strands allow precise control of the members to provide a desired shape and position of the body. In some embodiments, each member includes a plurality of the actuator strands. Moreover, in further embodiments, the plurality of actuator strands are separated into regions of each member and are controlled individually or in groups to provide separate control of the regions of each member.

Also, in some embodiments, the body includes at least one casing and a sensor assembly configured to detect an environmental characteristic of the cavity based on a parameter of the casing. The sensor assembly is configured to provide sensor feedback for inspecting the cavity and for navigating through the cavity. For example, in some embodiments, the sensor assembly detects when the casing contacts an obstacle and operation of the insertion apparatus can be changed to account for the obstacle. In some embodiments, each member includes a discrete casing and the members are flexibly coupled together by a plurality of joints. In further embodiments, the body includes a single casing that extends along a plurality of the members. In some embodiments, the casing encloses the phase change material and the actuator strands. As a result, the insertion apparatus is compact and modular and includes a distributed actuation system that provides precise positioning of the insertion apparatus within the cavity.

<FIG> is a schematic view of a system <NUM> including an insertion apparatus <NUM> including a body <NUM> that is rigidizable. Body <NUM> extends from an insertion end <NUM> to a steering end <NUM> and includes a plurality of members <NUM> flexibly coupled together. Each member <NUM> has a first configuration in which member <NUM> has a first stiffness and a second configuration in which member <NUM> has a second stiffness greater than the first stiffness. For example, at least a portion of body <NUM> is flexible to facilitate travel of body <NUM> through the cavity when at least one of members <NUM> is in the first configuration, and at least a portion of body <NUM> is rigid to maintain a selected shape of body <NUM> when at least one of members <NUM> is in the second configuration. In alternative embodiments, insertion apparatus <NUM> includes any body <NUM> that enables insertion apparatus <NUM> to operate as described herein.

In addition, according to the claimed invention, system <NUM> includes a controller <NUM> coupled to body <NUM> and configured to individually switch each member <NUM> between the first configuration and the second configuration. For example, in some embodiments, each member <NUM> includes a phase change material and controller <NUM> is configured to cause insertion apparatus <NUM> to switch the state of the phase change material between a first state and a second state. Controller <NUM> may be located remotely from insertion apparatus <NUM> and/or at least partly incorporated into insertion apparatus <NUM>.

Moreover, in the exemplary embodiment, each member <NUM> includes a casing <NUM>. Casing <NUM> may be plastic, metal, and/or any other suitable material. In the exemplary embodiment, each casing <NUM> is a hollow, closed-end cylinder constructed of a pliable material. In alternative embodiments, body <NUM> includes any casing <NUM> that enables insertion apparatus <NUM> to operate as described herein. For example, in some embodiments, body <NUM> includes a single casing <NUM> that extends along a plurality of members <NUM>.

In some embodiments, a sensor assembly <NUM> is coupled to and/or incorporated into casing <NUM>. Sensor assembly <NUM> is configured to detect environmental characteristics based on at least one parameter of casing <NUM>. For example, in some embodiments, a plurality of sensing electrodes are coupled to or integrated into casing <NUM> around the perimeter of casing <NUM>. In the exemplary embodiment, casing <NUM> includes a multi-layer structure including dielectric and conducting layers that form a part of sensor assembly <NUM>. Accordingly, sensor assembly <NUM> is configured to detect a change in the parameters of casing <NUM> such as a change in resistance between sensing electrodes coupled to casing <NUM>. The information from sensor assembly <NUM> is used to determine environmental characteristics of body <NUM> such as a position or orientation of body <NUM> or a force applied to body <NUM>. In alternative embodiments, insertion apparatus <NUM> includes any sensor assembly <NUM> that enables insertion apparatus <NUM> to operate as described herein.

Also, in the exemplary embodiment, body <NUM> further includes a plurality of joints <NUM> coupled between casings <NUM>. Joints <NUM> couple members <NUM> together and allow each member <NUM> to move relative to adjacent members <NUM>. For example, in some embodiments, each joint <NUM> includes a hinge attached to casings <NUM> of adjacent members <NUM>. In addition, in some embodiments, each joint <NUM> includes flexible electrical connections for wires and electrical components extending through body <NUM>. In alternative embodiments, body <NUM> includes any joint <NUM> that enables body <NUM> to function as described herein.

<FIG> is a schematic view illustrating a portion of body <NUM> of insertion apparatus <NUM> in a plurality of orientations. In the exemplary embodiment, insertion apparatus <NUM> includes at least one actuator strand <NUM> coupled to members <NUM> and configured to individually actuate members <NUM> between the plurality of orientations. For example, each member <NUM> is positionable between a first orientation in which member <NUM> extends at a first angle relative to a translation direction <NUM> of insertion apparatus <NUM>, a second orientation in which member <NUM> is aligned with translation direction <NUM>, and a third orientation in which member <NUM> extends at a second angle relative to translation direction <NUM>. The ability to position each member <NUM> in a plurality of orientations facilitates moving insertion apparatus <NUM> through cavity and around obstacles in the cavity and precisely positioning a maintenance device <NUM> relative to a target location. In addition, the ability to position each member <NUM> in different orientations allows body <NUM> to assume desired shapes. In alternative embodiments, members <NUM> are positionable in any manner that enables insertion apparatus <NUM> to operate as described herein.

<FIG> is a cross-sectional view of body <NUM> of insertion apparatus <NUM>. In the exemplary embodiment, each member <NUM> of body <NUM> includes casing <NUM>, a plurality of actuator strands <NUM>, phase change material <NUM>, and at least one phase regulator <NUM>. Actuator strands <NUM> extend longitudinally through members <NUM> and are positioned within an annular space defined between casing <NUM> and a conduit <NUM> of body <NUM>. Each actuator strand <NUM> is configured to selectively actuate at least a portion of member <NUM>. For example, in some embodiments, a shape or cross-sectional area of actuator strand <NUM> changes in response to a signal from an actuator controller <NUM> and the change in shape or cross-sectional area of one or more actuator strands <NUM> causes member <NUM> to change shape. In particular, actuation of each actuator strand <NUM> is coordinated with actuation or non-actuation of other actuator strands <NUM> to cause body <NUM> to have a desired shape. Acccording to the claimed invention, each actuator strand <NUM> has a length that is substantially equal to the length of member <NUM> such that actuator strands <NUM> extend along the entire length of members <NUM>. In alternative embodiments, insertion apparatus <NUM> includes any actuator strands <NUM> that enable insertion apparatus <NUM> to operate as described herein.

In addition, according to the claimed invention, insertion apparatus <NUM> includes at least one actuator controller <NUM> configured to send instructions to actuator strands <NUM> to cause actuator strands <NUM> to actuate body <NUM>. For example, the instructions may be electrical signals which activate/deactivate actuator strands <NUM>. Insertion apparatus <NUM> may include a single actuator controller <NUM> or a plurality of actuator controllers <NUM>. In the exemplary embodiment, a plurality of actuator controllers <NUM> are coupled to individual actuator strands <NUM> of members <NUM> and are configured to provide signals to individual actuator strands <NUM> to cause actuation of members <NUM>. In some embodiments, actuator controllers <NUM> are located at joints <NUM> between members <NUM> and are coupled to ends of actuator strands <NUM>. In further embodiments, actuator controllers <NUM> are located at locations along the length of members <NUM> and are coupled to actuate actuator strands <NUM> at the locations along the length of members <NUM>. In alternative embodiments, system <NUM> includes any actuator controller <NUM> that enables system <NUM> to operate as described herein.

Also, according to the claimed invention, phase change material <NUM> surrounds actuator strands <NUM> and is selectively rigidizable to maintain actuator strands <NUM> and member <NUM> in desired positions. Phase change material <NUM> allows movement or flexing of actuator strands <NUM> when member <NUM> is in the first configuration and inhibits at least some movement or flexing of actuator strands <NUM> when member is in the second configuration. Casing <NUM> encloses phase change material <NUM> and actuator strands <NUM> and is pliable to allow flexing of members <NUM> in the first configuration. Phase change material <NUM> is a material that has a first state, e.g., liquid or a semi-solid, under a first set of environmental conditions and a second state, e.g., solid, under a second set of environmental conditions. In some embodiments, phase change material <NUM> is a metal or a wax. In alternative embodiments, insertion apparatus <NUM> includes any phase change material <NUM> that enables insertion apparatus <NUM> to operate as described herein.

Moreover, in the exemplary embodiment, the state of phase change material <NUM> is controlled using phase regulators <NUM>. For example, each phase regulator <NUM> includes a thermoelectric element configured to regulate the state of phase change material <NUM> by controlling the temperature of phase change material <NUM>. Accordingly, to switch member <NUM> from the second configuration to the first configuration, phase regulator <NUM> delivers heat to phase change material <NUM> to heat phase change material <NUM> above a melting point. In some embodiments, phase change material <NUM> and phase regulator <NUM> are configured to provide a binary switching of member <NUM> between the first configuration and the second configuration. In further embodiments, the state of phase change material <NUM> is regulated to provide a graduated change between phases such that each member <NUM> has a plurality of intermediate configurations between the first configuration and the second configuration which provide different stiffness and levels of flexibility for body <NUM>. In alternative embodiments, insertion apparatus <NUM> includes any phase regulator <NUM> that enables insertion apparatus <NUM> to operate as described herein.

In addition, in the exemplary embodiment, a cross-sectional area of each member <NUM> is divided into a plurality of regions <NUM>, <NUM>, <NUM>, <NUM> that are individually rigidizable. In the exemplary embodiment, each member <NUM> includes first region <NUM>, second region <NUM>, third region <NUM>, and fourth region <NUM>. Each region <NUM>, <NUM>, <NUM> encompasses phase change material <NUM> and at least one actuator strand <NUM>. In addition, at least one actuator controller <NUM> and at least one phase regulator <NUM> are associated with each region <NUM>, <NUM>, <NUM>, <NUM> and configured to control the shape and rigidity of region <NUM>, <NUM>, <NUM>. For example, each phase regulator <NUM> is configured to regulate the state of phase change material <NUM> in a respective region <NUM>, <NUM>, <NUM>, <NUM> and each actuator controller <NUM> is configured to operate actuator strands <NUM> to actuate a respective region <NUM>, <NUM>, <NUM>, <NUM> of member <NUM>. In alternative embodiments, body <NUM> includes any regions that enable insertion apparatus <NUM> to operate as described herein.

Moreover, in the exemplary embodiment, body <NUM> further includes at least one conduit <NUM> extending from insertion end <NUM> to steering end <NUM> and configured to channel fluid to members <NUM> to facilitate regulating the temperature of phase change material <NUM>. In some embodiments, insertion apparatus <NUM> utilizes passive cooling in which heat from phase change material <NUM> is dissipated to fluid in conduit <NUM>. In further embodiments, insertion apparatus <NUM> includes an active thermal management system such as a cooling/heating system that heats/cools a fluid and pumps the fluid through conduit <NUM> and/or other portions of members <NUM> to regulate the temperature of phase change material <NUM> and other components of member <NUM>. In the exemplary embodiment, conduit <NUM> facilitates insertion apparatus <NUM> maintaining a uniform temperature of body <NUM> and enables insertion apparatus <NUM> to more reliably control the state of phase change material <NUM>.

Referring to <FIG>, in the exemplary embodiment, one or more wires <NUM> are positioned within conduit <NUM> and extend through body <NUM> from steering end <NUM> to insertion end <NUM>. Wires <NUM> convey signals and/or electrical power to members <NUM> and/or maintenance device <NUM> during operation of insertion apparatus <NUM>. In alternative embodiments, insertion apparatus <NUM> includes any wire <NUM> that enables insertion apparatus <NUM> to operate as described herein. In further embodiments, insertion apparatus <NUM> transmits and receives signals and/or power using any wired and/or wireless connections. For example, in some embodiments, a component, such as a harness or tether, extends from maintenance device <NUM> to the exterior of machine <NUM> and provides power to maintenance device <NUM>, allows maintenance device <NUM> to send and/or receive signals, and/or transmits mechanical force, fluids, or thermal energy to maintenance device <NUM>.

<FIG> is a schematic view of insertion apparatus <NUM> within a cavity <NUM> of a machine <NUM>. During operation, insertion apparatus <NUM> enters cavity <NUM> of machine <NUM> through any suitable access port or opening of machine <NUM>. For example, in some embodiments, insertion apparatus <NUM> enters and/or exits cavity <NUM> through any of an inlet, an exhaust, and/or an access port, such as an igniter, borescope, or fuel nozzle port. In the exemplary embodiment, body <NUM> of insertion apparatus <NUM> is sized and shaped to fit within and travel through cavity <NUM>. For example, body <NUM> has a height and width that are less than a clearance required to fit within cavity <NUM>. In addition, insertion apparatus <NUM> is configured to travel around obstacles in cavity <NUM> of machine <NUM>. In alternative embodiments, insertion apparatus <NUM> is any size and shape that enables insertion apparatus <NUM> to operate as described herein.

Also, in the exemplary embodiment, during operation, insertion apparatus <NUM> is used to inspect and/or repair any interior components of machine <NUM>. For example, in some embodiments, insertion apparatus <NUM> is positioned adjacent a portion of an interior surface <NUM> of machine <NUM> within cavity <NUM>. In some embodiments, insertion apparatus <NUM> detects a characteristic of interior surface <NUM>. For example, in some embodiments, insertion apparatus <NUM> is used to generate an image of interior surface <NUM> and the image is examined to determine the condition of machine <NUM> and assess whether repairs are necessary. In further embodiments, insertion apparatus <NUM> includes a sensor that detects characteristics of interior surface <NUM>. If repairs are necessary, in some embodiments, insertion apparatus <NUM> is used to repair interior surface <NUM>. After inspection and/or repair of interior surface <NUM>, insertion apparatus <NUM> exits machine <NUM> through any suitable access port or opening of machine <NUM>, such as via the route of entry.

Also, in the exemplary embodiment, insertion apparatus <NUM> includes at least one maintenance device <NUM> coupled to insertion end <NUM> of insertion apparatus <NUM> to allow insertion apparatus <NUM> to perform an inspection and/or repair operation within cavity <NUM> of machine <NUM>. Insertion apparatus <NUM> is configured to position maintenance device <NUM> at a target location adjacent interior surface <NUM>. In some embodiments, maintenance device <NUM> includes at least one sensor that is configured to contact surfaces. In alternative embodiments, insertion apparatus <NUM> includes any maintenance device <NUM> that enables insertion apparatus <NUM> to operate as described herein. For example, in some embodiments, maintenance device <NUM> of insertion apparatus <NUM> includes, without limitation, any of the following: an applicator, a drill, a grinder, a heater, a welding electrode, a sprayer, an optical sensor (e.g., visible, infrared, and/or multi-spectral sensor), a mechanical sensor (e.g., stylus profilometer, coordinate measurement probe, load transducer, linear variable differential transformer), a thermal sensor (e.g., pyrometer, thermocouple, resistance temperature detector), a magnetic sensor, an acoustic sensor (e.g., piezoelectric, microphone, ultrasound), and an electromagnetic sensor (e.g., eddy current, potential drop, x-ray).

<FIG> is a schematic view of insertion apparatus <NUM> traveling within cavity <NUM> of machine <NUM> with at least a portion of body <NUM> in a fist configuration in which body <NUM> has a first stiffness. <FIG> is a schematic view of insertion apparatus <NUM> traveling within cavity <NUM> of machine <NUM> with at least a portion of body <NUM> in a second configuration in which body <NUM> has a second stiffness greater than the first stiffness. The first and second configurations of members <NUM> of body <NUM> enable movement of insertion apparatus <NUM> through cavity <NUM> without insertion apparatus <NUM> being caught on objects. For example, as shown in <FIG>, body <NUM> is able to flex and bend around objects when at least one member <NUM> of body <NUM> is in the first configuration. As shown in <FIG>, at least a portion of body <NUM> is substantially rigid to maintain a desired shape and resist forces against body <NUM> when at least one member <NUM> of body <NUM> is in the second configuration. In addition, the second configuration of members <NUM> allows body <NUM> to provide leverage for insertion apparatus <NUM> to move within cavity <NUM> and/or for maintenance device <NUM> to perform a maintenance operation within cavity <NUM>.

In some embodiments, members <NUM> of insertion apparatus <NUM> are switched between the first configuration and the second configuration based on information relating to environmental conditions within cavity <NUM> and/or based on a location of insertion apparatus <NUM> within cavity <NUM>. For example, in some embodiments, at least a portion of insertion apparatus <NUM> switches between the first configuration and the second configuration based on feedback from sensors such as sensor assembly <NUM> coupled to casing <NUM>. In particular, sensor assembly <NUM> is configured to provide sensor feedback indicating contact with an obstacle. Accordingly, at least a portion of insertion apparatus <NUM> may switch from the first configuration to the second configuration such that members <NUM> contacting an obstacle are pliable. As a result, insertion apparatus <NUM> may prevent damage to insertion apparatus <NUM> and machine <NUM>.

<FIG> is a flow chart of an exemplary method <NUM> of inspecting cavity <NUM> (shown in <FIG>) using insertion apparatus <NUM> (shown in <FIG>). In reference to <FIG>, method <NUM> includes inserting <NUM> insertion end <NUM> of insertion apparatus <NUM> into cavity <NUM> and moving <NUM> insertion apparatus <NUM> through cavity <NUM> with at least one member <NUM> in the first configuration. At least a portion of body <NUM> is flexible and has a first stiffness that facilitates travel of body <NUM> through cavity <NUM> when member <NUM> is in the first configuration.

Also, method <NUM> includes changing <NUM> a shape of body <NUM> by actuating at least one member <NUM> using actuator strands <NUM>. For example, in some embodiments, actuator strands <NUM> in one or more regions <NUM>, <NUM>, <NUM>, <NUM> of one or more members <NUM> of body <NUM> are operated to actuate members <NUM> and cause body <NUM> to form a desired shape such as a curved shape.

In addition, method <NUM> includes switching <NUM> at least one member <NUM> from the first configuration to the second configuration. For example, in some embodiments, phase change material <NUM> in one or more regions <NUM>, <NUM>, <NUM>, <NUM> of one or more members <NUM> of body <NUM> is switched between a first state and a second state to switch member <NUM> between the first configuration and the second configuration. At least a portion of body <NUM> is rigid and has a second stiffness greater than the first stiffness when member <NUM> is in the second configuration. Accordingly, when at least one member <NUM> is in the second configuration, body <NUM> is able to resist forces acting on insertion apparatus <NUM> and provide leverage for insertion apparatus <NUM> to be positioned within cavity <NUM> and perform maintenance operations.

In some embodiments, method <NUM> includes positioning maintenance device <NUM> coupled to insertion end <NUM> of insertion apparatus <NUM> at a target location within cavity <NUM>, and performing a maintenance operation using maintenance device <NUM>. In some embodiments, the maintenance operation includes inspecting and/or repairing interior surface <NUM> of machine <NUM>.

Moreover, in some embodiments, method <NUM> includes sensing at least one environmental condition of insertion apparatus <NUM> using a sensor assembly such as sensor assembly <NUM> coupled to casing <NUM>. For example, in some embodiments, one or more members <NUM> of body <NUM> automatically switch between the first configuration and the second configuration when casing <NUM> contacts an obstacle within cavity <NUM>.

An exemplary technical effect of the methods, systems, and apparatus described herein includes at least one of: (a) reducing the time to inspect and/or repair a machine; (b) increasing the accessibility of difficult-to-reach locations within a cavity for inspection and/or in situ repair; (c) reducing the time that machines are out of service for maintenance; (d) increasing the precision and/or reliability of inspection and repair of machines; (e) reducing unplanned service outages for machines; and (f) enhancing data capture for use in quantifying and/or modeling the service condition of at least some components of the machine.

Exemplary embodiments of methods and systems for use with machines are not limited to the specific embodiments described herein, but rather, components of systems and/or steps of the methods may be utilized independently and separately from other components and/or steps described within the scope of the appended claims. For example, the methods and systems may also be used in combination with other systems requiring inspection and/or repair of components, and are not limited to practice with only the systems and methods as described herein. Rather, the exemplary embodiment can be implemented and utilized in connection with many other applications, equipment, and systems that may benefit from using an insertion apparatus for inspection and/or repair.

Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only.

Claim 1:
An insertion apparatus (<NUM>) comprising:
an insertion end (<NUM>) positionable within a cavity (<NUM>) of a machine and configured to travel through the cavity (<NUM>);
a steering end (<NUM>) opposite said insertion end (<NUM>);
a body (<NUM>) extending from said insertion end (<NUM>) to said steering end (<NUM>), and sized to fit within the cavity (<NUM>),
wherein said body (<NUM>) comprises a plurality of members (<NUM>) flexibly coupled together and individually actuated, each member of said plurality of members (<NUM>) including at least one actuator strand (<NUM>) having a length that is substantially equal to a length of the corresponding member (<NUM>), wherein at least one member of said plurality of members (<NUM>) has a first configuration in which said at least one member of said plurality of members (<NUM>) has a first stiffness and a second configuration in which said at least one member of said plurality of members (<NUM>) has a second stiffness greater than the first stiffness, wherein at least a portion of said body (<NUM>) is flexible to facilitate travel of said body (<NUM>) through the cavity (<NUM>) when said at least one member of said plurality of members (<NUM>) is in the first configuration, and wherein said at least a portion of said body (<NUM>) is configured to maintain a selected shape when said at least one member of said plurality of members (<NUM>) is in the second configuration; and
at least one actuator controller (<NUM>) coupled to said at least one actuator strand and configured to send a signal to said at least one actuator strand to cause actuation of said corresponding member, the signal operable to change a shape or cross-sectional area of said at least one actuator strand,
wherein said at least one member of said plurality of members (<NUM>) comprises a phase change material (<NUM>) configured to switch between a first state corresponding to the first configuration and a second state corresponding to the second configuration,
wherein the phase change material (<NUM>) surrounds the at least one actuator strand (<NUM>) and is selectively rigidizable to maintain the at least one actuator strand (<NUM>) and member (<NUM>) in desired positions.