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A novel porous polydimethylsiloxane (PDMS)-based capacitive pressure sensor was fabricated by optimizing the dielectric layer porosity for wide-range pressure sensing applications in the sports field. The pressure sensor consists of a porous PDMS dielectric layer and two fabric-based conductive electrodes. The porous PDMS dielectric layer was fabricated by introducing nitric acid (HNO3) into a mixture of PDMS and sodium hydrogen bicarbonate (NaHCO3) to facilitate the liberation of carbon dioxide (CO2) gas, which induces the creation of porous microstructures within the PDMS dielectric layer. Nine different pressure sensors (PS1, PS2,..., PS9) were fabricated in which the porosity (pore size, thickness) and dielectric constant of the PDMS dielectric layers were varied by changing the curing temperature, the mixing proportions of the HNO3/PDMS concentration, and the PDMS mixing ratio. The response of the fabricated pressure sensors was investigated for the applied pressures ranging from 0 to 1000 kPa. A relative capacitance change of ∼100, ∼323, and ∼485% was obtained by increasing the curing temperature from 110 to 140 to 170 °C, respectively. Similarly, a relative capacitance change of ∼170, ∼282, and ∼323% was obtained by increasing the HNO3/PDMS concentration from 10 to 15 to 20%, respectively. In addition, a relative capacitance change of ∼94, ∼323, and ∼460% was obtained by increasing the PDMS elastomer base/curing agent ratio from 5:1 to 10:1 to 15:1, respectively. PS9 exhibited the highest sensitivity over a wide pressure sensing range (low-pressure ranges (

A fabric based porous polydimethylsiloxane (PDMS) pressure sensor was developed and the effect of curing temperature on the porosity as well as the sensitivity was investigated. Three different porous PDMS dielectric layers (D1, D2 and D3) were prepared by curing a mixture of PDMS, sodium hydrogen bicarbonate (NaHCO 3 ), and nitric acid (HNO 3 ) at 110 $^{\circ}C$, 140$^{\circ}C$ and 170$^{\circ}C$, respectively. The top and bottom electrodes of the pressure sensor were fabricated by screen printing silver (Ag) on a thermoplastic polyurethane (TPU) film. The screen-printed Ag-TPU film was permanently attached to a fabric using heat lamination process. Three pressure sensors, PS1, PS2 and PS3 were assembled by sandwiching the porous dielectric layers D1, D2 and D3 between the top and bottom electrodes, respectively. An average pore size of $411 \mu \mathrm{m}, 496 \mu \mathrm{m}$, and $502 \mu \mathrm{m}$ was measured for D1, D2 and D3, respectively. A relative capacitance change of $\sim 100$%, $\sim$ 323%, and $\sim$ 485% was obtained for the pressure sensors PS1, PS2, PS3, respectively, for varying applied pressures ranging from 0 to 1000 kPa. The effect of curing temperatures on the thickness as well as the dielectric constant of the porous PDMS layer, which in turn changes the sensitivity of the pressure sensors, was investigated and is presented in this paper.

A novel porous polydimethylsiloxane (PDMS) capacitive pressure sensor was fabricated on a fabric platform using additive screen printing process. The porous PDMS was prepared using a mixture of PDMS, sodium hydrogen bicarbonate (NaHCO3) and nitric acid (HNO3) and implemented as a dielectric layer. The fabric based top and bottom electrodes were developed by screen printing silver (Ag) ink on thermoplastic polyurethane (TPU) and permanently attaching it on to a fabric using heat lamination process. The capacitive response of the pressure sensor was recorded for varying pressures ranging from 0 to 900 kPa. A relative capacitance change of ~10%, ~180% and ~300% was obtained for the applied pressure ranges of 0 to 20 kPa, 50 to 200 kPa and 300 to 900 kPa, respectively. The detailed fabrication process of the pressure sensor as well as its capacitive response is analyzed and reported in this paper.

A resistive flexible humidity sensor based on carbon nanotubes (CNT) was designed and fabricated. Screen and gravure printing processes were used for the fabrication of the humidity sensor containing interdigitated electrodes (IDE), a sensing layer and a meandering conductive heater. The capability of the printed sensor was investigated by subjecting it to relative humidity (RH) ranging from 30% to 60%. This response demonstrated an overall resistance change of ~29% when the sensor was subjected to 60% RH, when compared to 30% RH. A maximum hysteresis of ~5.8%, at 40% RH, was calculated for the resistive response of the sensor. The fabrication method and sensor response are analysed and presented in this paper.

In this paper, we present the design and implementation of a smart strain based sensory glove for remote control (RC) car applications. This glove would control the RC car with individual finger movements. Laser carbonization was implemented as a fabrication method for developing strain sensors which were integrated on a Polydimethylsiloxane (PDMS) platform. Various sensor designs were fabricated and tested to determine the effectiveness of the glove design. This laser carbonization method resulted in a directional anisotropic characteristic with a relative resistance change of 170× when bent from an angle of 0 ° to 145 ° (complete finger bend).