Low-cost flexible pressure sensor based on dielectric elastomer film with micro-pores

Point-of-use robotic sensors for simultaneous pressure detection and chemical analysis

“…12,[17][18][19] For targeted applications, capacitive pressure sensors are preferred due to the advantages of low sensitivity to temperature and relative humidity changes, low power consumption, high reproducibility, and static pressure detection capability. 18,20,21 The sensitivity of a capacitive sensor is tunable by adjusting the dielectric compressibility; for instance, the sensitivity is increased by choosing softer materials, i.e. elastomers with lower elastic moduli, and by designing porous structures 20-25 that further lower elastic moduli from 1 GPa in solid films to around 1-10 MPa in foam dielectrics.…”

“…20 Indeed, the sensitivity of porous structures was found to be around 1-2 orders of magnitude higher compared to that of non-porous dielectrics using the same material. [22][23][24][25] Porous structures with well-defined patterns usually exhibit higher sensitivity than arbitrary patterns; 12,21,23 however, their fabrication is highly complex. Here, the foam structures of the pressure sensors are easy to fabricate and are optimized by air-to-solid volume ratios for sensitivity and reproducibility to the range of pressures typical for object manipulation in the low (1-10 kPa) and medium (10-30 kPa) pressure regimes.…”

Flexible and transparent capacitive pressure sensor with patterned microstructured composite rubber dielectric for wearable touch keyboard application

“…Recently, high sensitivity, large-scale and high resolution pressure sensor have made significant breakthrough based on different physical transduction mechanisms, such as piezoelectricity, piezoresistivity and capacitance. Compared with the other types of pressure sensors, capacitive pressure sensors with high accuracy in detecting static loads, low power consumption, low hysteresis and large response ranges, have obtained great success in the field of consumer electronics, including biometric identification [13,14], touchpads [7,15] and touchscreens.…”

“…However, the inherent characteristics of a single dielectric limit the further development of capacitive pressure sensors. Therefore, to increase the sensing performance, some effective methods have been investigated, including doping fillers in insulating elastic dielectrics [16][17][18][19][20], introducing the ordered microstructures to the dielectric [14,[20][21][22][23][24], changing the internal microstructure of the dielectric [15,25], and so on. For example, Schwartz et al [26] reported a flexible capacitive pressure sensor embedded capacitive sensing element with a microstructured elastomer layer which revealed a fast response within a millisecond range and a great mechanical flexibility.…”

Enhanced Sensitivity of Iontronic Graphene Tactile Sensors Facilitated by Spreading of Ionic Liquid Pinned on Graphene Grid

“…When a larger ionic liquid droplet with 600 µm diameter is used, a capacitance change from 1 to 250 pF is observed under a pressure of 8 kPa (Figure S4 in the Supporting Information). In this case, the sensitivity is calculated to be 31.1 kPa −1 , which is one of the highest values reported in the medium‐pressure range (> a few kPa) so far (see Table S1 in the Supporting Information) . Although higher sensitivities have been reported in the previous reports, these values are typically obtained in extremely low pressure regimes (below 1 kPa) .…”