Fiber optic load sensing device

A load sensing device adapted to be mounted transversely on a roadway and to receive downwardly applied loads of the type imparted by an automotive vehicle wheel comprising

• a longitudinal envelope having spaced apart peripheral walls defining an interior space therebetween in a region of said envelope adapted to receive said load, said walls remaining substantially longitudinally parallel to one another substantially throughout the region of said envelope adapted to receive said load, at least one of said walls in said region having an elastically deformable portion having a first interior surface deflectable into said interior space towards an opposing second interior surface of one of said peripheral walls upon the application of said load to said envelope;
• a relatively soft compressible elastomeric insert embedded in said interior space of said envelope;
• a fiber optic cable longitudinally positioned within said interior space of said envelope and resting against said insert, said fiber optic cable comprising an optical fiber having a first end adapted to receive light and a second end adapted to permit the exit of said light, said fiber optic cable being subject to sufficent deformation into said insert upon deflection of said first interior surface caused by application of said load so as to permit localized bending of said optical fiber sufficient to substantially alter the light transmitted through the optical fiber;
• and
• means for preventing complete compression of said elastomeric insert where said fiber optic cable rests against said elastomeric insert during application of said load when said device is mounted on the surface of the roadway.