An insertion apparatus (102) includes an insertion end (106) positionable within a cavity (146) and configured to travel through the cavity, a steering end (108) opposite the insertion end, and a body (104) extending from the insertion end to the steering end and sized to fit within the cavity. The body includes a plurality of members (110) flexibly coupled together and individually actuated. Each member of the plurality of members includes at least one actuator strand (120). At least one member of the plurality of members has a first configuration in which the at least one member of the plurality of members has a first stiffness and a second configuration in which the at least one member of the plurality of members has a second stiffness greater than the first stiffness. At least a portion of the body is flexible to facilitate travel of the body through the cavity when the at least one member of the plurality of members is in the first configuration. The at least a portion of the body is configured to maintain a selected shape when the at least one member of the plurality of members is in the second configuration.