Disclosed herein are structure and method for connecting a fabric sensor and a digital yarn. The structure includes a sheet-type member which is configured to be worn on a body of a wearer, a first fabric sensor which is provided on the sheet-type member and senses a biological signal, a digital yarn which is provided on the first fabric sensor and has a peeled portion that is electrically connected to the first fabric sensor, a sewing yarn which couples a portion of the digital yarn to the first fabric sensor by sewing, and a second fabric sensor which is coupled to the first fabric sensor and covers an upper portion of the peeled portion.

A system of fibers, filaments, and/or other electrically conductive materials forms an electrically conductive-to-semi-conductive yarn that can be assembled into a textile for measurement of voltage, current, resistance, capacitance, inductance, RF, and/or EM signals. Textiles are formed through weaving, knitting, lacing, and/or non-woven mechanical methods of yarn-making into 2D/3D structures. Textile-based electrodes can be formed via folding, cutting, layering, sewing, and/or embroidering patterns to control signal transmission within/through the electrode. Multiple electrodes are positioned on a surface (e.g., a body) to sequentially or simultaneously perform multiple diagnostic modalities (e.g., electrocardiography, electromyography, electrooculography, electroencephalogram, bioelectrical impedance analysis, skin impedance analysis, and/or electrodermal activity). These modalities are multiplexed using an optimized electrode set through amplitude and frequency deconvolution and filtering algorithms to minimize the quantity of electrodes and connections on the surface while maximizing signal-to-noise ratio, differential and common mode noise rejection, and elimination of external signals (e.g., RF and EM noise).

A seat heater includes a substrate. A formed heating wire is disposed on the substrate. A sewing thread attaches the formed heating wire to the substrate. A method of fabricating the seat heater includes forming a straight heating wire into a formed heating wire having miniature wave shape, feeding the formed heating wire onto a substrate, and attaching the formed heating wire onto the substrate by sewing a thread.

A system of fabric-based devices designed as transistors with tri-state behavior that can measure any geometries on 2D and 3D surfaces. The devices are constructed from layers of conductive materials and flexible sheets that allow signals to selectively cross between layers. Multiple layers of conductive signals can be achieved by controlling the tension of the top and bottom thread, and interlayering conductive, semiconductive, insulating, and semi-porous materials around a sensing layer. The layers can be further modified to include folds and cuts that allow for 2D and 3D bending, stretching, twisting, and curves. Large sheets of devices can be organized into grid-like matrixes, with signal wires connected in a multiplexed fashion to minimize the amount of threads to simplify construction and device communication to a central processing unit.

A system of fabric-based devices designed as transistors with tri-state behavior that can measure any geometries on 2D and 3D surfaces. The devices are constructed from layers of conductive materials and flexible sheets that allow signals to selectively cross between layers. Multiple layers of conductive signals can be achieved by controlling the tension of the top and bottom thread, and interlayering conductive, semiconductive, insulating, and semi-porous materials around a sensing layer. The layers can be further modified to include folds and cuts that allow for 2D and 3D bending, stretching, twisting, and curves. Large sheets of devices can be organized into grid-like matrixes, with signal wires connected in a multiplexed fashion to minimize the amount of threads to simplify construction and device communication to a central processing unit.

A method for producing a smart textile includes stitching with a conductive thread from a first point outside a segmented area that is set on a sheet material toward a second point on the segmented area. An embroidery with the conductive thread is sewn from the second point as a starting point to apply a segment in the segmented area. These series of steps are executed without performing a process for cutting the conductive thread by stopping the sewing process of the conductive thread.