The invention relates to a method of producing a fibrillary dry adhesive material having a plurality of fibrils. Furthermore, the invention relates to a fibrillar dry adhesive material in particular having liquid super-repellency.

Provided are systems and methods for the post-treatment of dry adhesive microstructures. The microstructures may be post-treated to comprise mushroom-like flaps at their tips to interface with the contact surface. In some aspects, a change in material composition of the microstructures in a dry adhesive may affect mechanical properties to enhance or diminish overall adhesive performance. For example, conductive additives can be added to the material to improve adhesive performance. In other aspects, microstructures comprising conductive material may allow for pre-load engagement sensing systems to be integrated into the microstructures.

Dry adhesives and methods for forming dry adhesives. A method of forming a dry adhesive structure on a backing material, comprises: forming a template backing layer of energy sensitive material on the backing material; forming a template layer of energy sensitive material on the template backing layer; exposing the template layer to a predetermined pattern of energy; removing a portion of the template layer related to the predetermined pattern of energy, and leaving a template structure formed from energy sensitive material and connected to the substrate via the template backing layer.

Provided are systems and methods for the post-treatment of dry adhesive microstructures. The microstructures may be post-treated to comprise mushroom-like flaps at their tips to interface with the contact surface. In some aspects, a change in material composition of the microstructures in a dry adhesive may affect mechanical properties to enhance or diminish overall adhesive performance. For example, conductive additives can be added to the material to improve adhesive performance. In other aspects, microstructures comprising conductive material may allow for preload engagement sensing systems to be integrated into the microstructures.

A device having a structured coating for adhering to rough, in particular, biological surfaces, includes a carrier layer, wherein a plurality of protrusions is arranged on the carrier layer, which protrusions each comprise at least one stem having an end face pointing away from the surface, and wherein a further layer is arranged at least on the end face, wherein the layer has a lower modulus of elasticity and is in the form of a film that interconnects the protrusions. The film can also be in the form of a removable film.

This invention identifies important geometric parameters of an adhesive microfiber with mushroom-shaped tip for improving and optimizing adhesive ability. The magnitude of pull-off stress is dependent on a wedge angle γ and the ratio of the tip radius to the stalk radius β of the mushroom-shaped fiber. Pull-off stress is also found to depend on a dimensionless parameter x, the ratio of the fiber radius to a length-scale related to the dominance of adhesive stress. Finally, the shape of edge tip, where the surface and sides of the mushroom-shaped tip join, is a factor that impacts strength of adhesion. Optimizing ranges for these parameters are identified.

The present invention is a method for controlling flatness of a wafer including the steps of: providing a holding member having a holding surface including a plurality of segments, where each of the plurality of segments includes a dry adhesive fiber structure; making the holding surface of the holding member adhere to a wafer to make the holding member hold the wafer; obtaining information on flatness of the wafer by measuring flatness of the wafer to; and releasing adhesion of the dry adhesive fiber structures to the wafer in a part of the plurality of segments of the holding surface of the holding member based on the information on flatness. This can provide: a method for controlling flatness by which flatness of a wafer can be controlled sufficiently.

Resilient members having near-surface architectures including microstructures for controlling friction are provided. A film-terminated array of fibrils having a sharp film/fibril juncture exhibits an unexpectedly large enhancement of adhesion, static friction and sliding friction. The enhancement is provided against rough indenters. A film-terminated array of elongated ridges and valleys unexpectedly exhibits low adhesion, and an unexpectedly large enhancement of sliding friction. The film-terminated ridge/valley design provides an anisotropic structure with direction-dependent frictional properties. The increase in sliding friction force varies as a function of interfibrillar spacing, and corresponds to a mode in which buckling of the terminal film occurs. The near surface architectures may be designed with varying scales and varying parameters to provide performance characteristics tailored to various applications. By way of example, the film-terminated ridge/valley array may be incorporated in motor vehicles tires to provide low rolling resistance and high sliding friction allow for high-performance braking during vehicle operation.

A structure (140) for adhering to a surface so as to support a desired weight includes a substrate (110) and a polymer layer (120). The polymer layer (120) is mounted on the substrate (110). A plurality of flaps (142) are drawn from the polymer layer (120). Each of the plurality of flaps (142) have dimensions and a density so that when the plurality of flaps (142) are placed against the surface (400) and when a coherent shear force is applied thereto, the plurality of flaps (142) will adhere to the surface (400) with a strength sufficient to support the desired weight. Each of the plurality of flaps (142) includes a first side (210) and an opposite second side (212). At least one of the first side or the second side is meniscus shaped.

A microstructured surface is disclosed capable of immobilizing or resisting displacement forces with respect to a target surface. The microstructured surface is capable of generating capillary bridges with a target surface. The capillary bridges can be further stabilized to generate a novel liquid enhanced adhesion mechanism.