We present a shape memory polymer (SMP) surface with repeatable, very strong (>18 atm), and extremely reversible (strong to weak adhesion ratio of >1 × 10(4)) dry adhesion to a glass substrate. This was achieved by exploiting bulk material properties of SMP and surface microstructuring. Its exceptional dry adhesive performance is attributed to the SMP's rigidity change in response to temperature and its capabilities of temporary shape locking and permanent shape recovery, which when combined with a microtip surface design enables time-independent control of contact area.

Robust and inexpensive dry adhesives would have a multitude of potential applications, but replicating the impressive adhesive organs of many small animals has proved challenging. A substantial body of work has been produced in recent years which has illuminated the many mechanical processes influencing a dry adhesive interface. The especially potent footpads of the tokay gecko have inspired researchers to develop and examine an impressive and diverse collection of artificial fibrillar dry adhesives, though study of tree frogs and insects demonstrate that successful adhesive designs come in many forms. This review discusses the current theoretical understanding of dry adhesive mechanics, including the observations from biological systems and the lessons learned by recent attempts to mimic them. Attention is drawn in particular to the growing contingent of work exploring ideas which are complimentary to or an alternative for fibrillar designs. The fundamentals of compliance control form a basis for dry adhesives made of composite and “smart,” stimuli-responsive materials including shape memory polymers. An overview of fabrication and test techniques, with a sampling of performance results, is provided.

We present a micromanufacturing method for constructing microsystems, which we term 'micro-masonry' based on individual manipulation, influenced by strategies for deterministic materials assembly using advanced forms of transfer printing. Analogous to masonry in construction sites, micro-masonry consists of the preparation, manipulation, and binding of microscale units to assemble microcomponents and microsystems. In this paper, for the purpose of demonstration, we used microtipped elastomeric stamps as manipulators and built three dimensional silicon microstructures. Silicon units of varied shapes were fabricated in a suspended format on donors, retrieved, delivered, and placed on a target location on a receiver using microtipped stamps. Annealing of the assembled silicon units permanently bound them and completed the micro-masonry procedure.

Transfer printing, a method to transfer microobjects using polymeric stamps, has been demonstrated either as a parallel process with high throughput, or as a low throughput process allowing individual manipulation of microobjects. This work presents a unique transfer printing approach which enables arbitrary pattern transfer from an array of microobjects via localized control of adhesion. This approach relies on thermally induced shape change of shape memory polymer (SMP) stamp arrays with carbon black‐composite (CBSMP) microstructuring. Heat is delivered first globally by a resistive heater, facilitating parallel microobject pickup, then locally by laser illumination absorbed within the CBSMP during printing, enabling precise and selective microobject release with packing density only limited by the spot size of the accompanying laser system. The thermal response of the CBSMP system is investigated computationally using experimentally measured laser power absorption within the CBSMP system and compared with high speed photography. Several transfer printing demonstrations are provided to indicate the robust microassembly capabilities of the approach. This work provides transfer printing‐based material integration with a path toward high process scalability and flexibility.

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