Embodiments of the invention include a fracture ring sensor and a method of using the same to detect out of tolerance forces. Aspects of the invention include a product having a defined an out of tolerance force, a fracture ring sensor, and a mounting assembly coupling the fracture ring sensor to the product. The fracture ring sensor is patterned with a conductive trace and is manufactured to break when subjected to a predetermined amount of force. The predetermined amount of force is substantially equal to a percentage of the out of tolerance force of the product.

Embodiments of the invention include a fracture ring sensor and a method of using the same to detect out of tolerance forces. Aspects of the invention include a product having a defined an out of tolerance force, a fracture ring sensor, and a mounting assembly coupling the fracture ring sensor to the product. The fracture ring sensor is patterned with a conductive trace and is manufactured to break when subjected to a predetermined amount of force. The predetermined amount of force is substantially equal to a percentage of the out of tolerance force of the product.

A transducer for assisting in measuring displacement or strain in an object of interest is described. A plate has at least two end sections for mounting the transducer. It comprises a flexible connection between the two end sections. The flexible connection comprises a plurality of rigid portions and flexible interconnections between the rigid portions for allowing relative movement of the rigid portions with respect to each other. The flexible connection has a central section substantially having a U-shape comprising two rigid portions spaced from each other over a distance and adapted for positioning a strain sensing element at the spacing in between said two rigid portions. The rigid portions and flexible interconnections are arranged so that a displacement applied to the end sections results in a relative displacement at the spacing in the central section that is larger than the relative displacement applied to the end sections.

A transducer for assisting in measuring displacement or strain in an object of interest is described. A plate has at least two end sections for mounting the transducer. It comprises a flexible connection between the two end sections. The flexible connection comprises a plurality of rigid portions and flexible interconnections between the rigid portions for allowing relative movement of the rigid portions with respect to each other. The flexible connection has a central section substantially having a U-shape comprising two rigid portions spaced from each other over a distance and adapted for positioning a strain sensing element at the spacing in between said two rigid portions. The rigid portions and flexible interconnections are arranged so that a displacement applied to the end sections results in a relative displacement at the spacing in the central section that is larger than the relative displacement applied to the end sections.

A vehicle seat assembly including a seat frame assembly including a seat base and a seat back pivotally connected to the seat base. The seat back includes at least one resin fuse arranged in the seat back to indicate structural loading in the vehicle seat assembly above a tolerance loading. The at least one resin fuse includes an aperture extending through the seat back and comprising a flange encircling the aperture and extending generally perpendicular to the seat back, and an indicator bar extending across a diameter of the aperture. The aperture is open on either side of the indicator bar.

A vehicle seat assembly including a seat frame assembly including a seat base and a seat back pivotally connected to the seat base. The seat back includes at least one resin fuse arranged in the seat back to indicate structural loading in the vehicle seat assembly above a tolerance loading. The at least one resin fuse includes an aperture extending through the seat back and comprising a flange encircling the aperture and extending generally perpendicular to the seat back, and an indicator bar extending across a diameter of the aperture. The aperture is open on either side of the indicator bar.

An electro-mechanical fuse is provided and includes a chassis component, an extrusion disposed on a monitored component which is disposable proximate to the chassis component and a sensor. The sensor is mounted to the chassis component. The sensor is mechanically breakable in power-on and power-off conditions by the extrusion as a result of a predefined action of or relative to the monitored component. The sensor electrically signals an occurrence of the mechanical breakage during power-on conditions following mechanical breakage.

An electro-mechanical fuse is provided and includes a chassis component, an extrusion disposed on a monitored component which is disposable proximate to the chassis component and a sensor. The sensor is mounted to the chassis component. The sensor is mechanically breakable in power-on and power-off conditions by the extrusion as a result of a predefined action of or relative to the monitored component. The sensor electrically signals an occurrence of the mechanical breakage during power-on conditions following mechanical breakage.

In one aspect, a load cell includes an elastic body, first optical unit, second optical unit, detector, and computation unit. The first optical unit has a light source, a first diffraction grating on which light from the light source is incident, and a light-receiving unit. The first optical unit is fixed to a first end portion of the elastic body and arranged within a hollow portion of the elastic body. The second optical unit has a second diffraction grating on which diffracted light from the first diffraction grating is incident to generate interference light. The second optical unit is fixed to a second end portion of the elastic body and arranged within the hollow portion. The detector detects the interference light. The computation unit computes a relative displacement amount of the second diffraction grating relative to the first diffraction grating on the basis of a signal obtained by the detector.

In one aspect, a load cell includes an elastic body, first optical unit, second optical unit, detector, and computation unit. The first optical unit has a light source, a first diffraction grating on which light from the light source is incident, and a light-receiving unit. The first optical unit is fixed to a first end portion of the elastic body and arranged within a hollow portion of the elastic body. The second optical unit has a second diffraction grating on which diffracted light from the first diffraction grating is incident to generate interference light. The second optical unit is fixed to a second end portion of the elastic body and arranged within the hollow portion. The detector detects the interference light. The computation unit computes a relative displacement amount of the second diffraction grating relative to the first diffraction grating on the basis of a signal obtained by the detector.