Electroadhesion with application to touchscreens

Abstract

There is growing interest in touchscreens displaying tactile feedback due to their tremendous potential in consumer electronics.

Electroadhesion for soft adhesive pads and robotics: theory and numerical results

“…where p 0 is the (external) applied pressure. Intuitively, one expect this approach to be accurate when the interaction force between the surfaces is long-range, and a similar approach has been used for the attraction resulting from capillary bridges [23,24] and also in an earlier study of electroadhesion [13][14][15]. Using (16) and (17) we have:…”

“…The electroadhesive force can be derived by the Maxwell stress tensor method [13][14][15][16][17][18]21]. We calculate the electroadhesive force between the two solids when the surfaces are separated by a distance u (see Fig.…”

“…In the so-called small-slope approximation, and assuming the surface roughness varies rapidly with the lateral coordinate compared to the electric potential V (x, t), the approach of Ref. [13,15] can be used to average over u, i.e., to perform an ensemble average over different realizations of the randomly rough surface. Note that the probability distribution of interfacial separations, P (p, u), depends on F (t) (the attractive force F (t) pulls the surfaces into closer contact and hence reduce the surface separation u(x, t)), but this can be taken into account using the mean-field approach described in Ref.…”

“…Note that the probability distribution of interfacial separations, P (p, u), depends on F (t) (the attractive force F (t) pulls the surfaces into closer contact and hence reduce the surface separation u(x, t)), but this can be taken into account using the mean-field approach described in Ref. [13,15], and which we now briefly summarize.…”

“…In these cases the adhesive pad must be built from an elastically soft material in order to increase the contact area and hence the friction force. Modeling of electroadhesive forces has been based on the parallel-plate-capacitor structure [12][13][14][15] when an electroadhesion pad is contacting a conductive or semiconductive substrate material, and the coplanar-platecapacitor structure [16][17][18] when an electroadhesion pad is contacting an insulating substrate material.…”