Fibre Optic Cables

A fibre optic sensing system comprising:

• a fibre optic cable structure comprising:
• (i) an optical fibre;
• and (ii) a bend inducer that is responsive to an environmental parameter to control bending of the optical fibre;
• wherein the bend inducer is configured to adopt a first configuration at a first value of the environmental parameter that induces a first curvature of the optical fibre and to adopt a second configuration at a second, different, value of the environmental parameter that induces a second, different, curvature of the optical fibre such that a change in value of the environmental parameter imparts a bending force on the optical fibre
• an interrogator unit for interrogating the optical fibre with electromagnetic radiation to provide fibre optic sensing.

A fibre optic cable structure comprising:

• an optical fibre;
• and
• a force transformer configured to bend in response to a change in an environmental parameter;
• wherein the force transformer is configured to adopt a curvature that depends on a static value of the environmental parameter such that a change in the value of the environmental parameter results in a change in curvature of the force transformer that induces a curvature of the optical fibre to change.