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The tight coupling of shape transformation, stiffness tuning, and self‐sensing that biological organisms exhibit has long served as inspiration for next‐generation soft robots. However, most current soft robots rely on intrinsically soft materials for actuation, separately embedded sensors for sensing, and have fixed stiffness once fabricated. Large gaps remain between these soft robots and biological organisms where multifunctionality is realized within an integrated body. Herein, a new class of robotic structures from architectured particle assemblies is introduced. They combine three functions: shape changing, stiffness variation, and self‐sensing into one monolithic structure. Unlike traditional entirely soft robots, the design utilizes the geometric contacts of stiff, architectured particles under confining pressure to achieve these functions. The applications of these structures by designing smart self‐sensing architectures and soft grippers are demonstrated. The design provides a new paradigm of multifunctional robotic structures, with potential multiscale applications in adaptive robots, smart devices, and reconfigurable architectures. [ABSTRACT FROM AUTHOR]

Octopus suckers offer remarkable adhesion performance against nonporous surfaces and have inspired extensive research to develop artificial adhesives. However, most of existing octopus‐inspired adhesives are either passive without an actuation strategy or active but not energy efficient. Here, a novel design of a magnetically actuated, energy‐efficient smart adhesive with rapidly tunable, great switchable, and highly reversible adhesion strength inspired by the elastic energy storage mechanism in octopus suckers is reported. The smart adhesive features two cavities separated by an elastic membrane with the upper cavity filled with magnetic particles while the lower one empty. The deformation of the elastic membrane can be actively controlled by an external magnetic field to change the cavity volume, thus generating a cavity‐pressure‐induced adhesion. Systematically experimental and theoretical studies reveal the fundamental aspects of design and operation of the smart adhesive and give insights into the underlying adhesion mechanisms. Demonstrations of this smart adhesive in transfer printing and manipulation of various surfaces in both dry and wet environments illustrate the potential for deterministic assembly and industrial or robotic manipulation. [ABSTRACT FROM AUTHOR]

Transfer printing, as an important assembly technique, has attracted much attention due to its valuable merits to develop novel forms of electronics such as stretchable inorganic electronics requiring the heterogeneous integration of inorganic materials with soft elastomers. Here, we report on a laser-driven programmable non-contact transfer printing technique via a simple yet robust design of active elastomeric microstructured stamp that features cavities filled with air and embedded under the contacting surface, a micro-patterned surface membrane that encapsulates the air cavities and a metal layer on the inner-cavity surfaces serving as the laser-absorbing layer. The micro-patterned surface membrane can be inflated dynamically to control the interfacial adhesion, which can be switched from strong state to weak state by more than three orders of magnitude by local laser heating of the air in the cavity with a temperature increase below 100°C. Theoretical and experimental studies reveal the fundamental aspects of the design and fabrication of the active elastomeric microstructured stamp and the operation of non-contact transfer printing. Demonstrations in the programmable transfer printing of micro-scale silicon platelets and micro-scale LED chips onto various challenging receivers illustrate the extraordinary capabilities for deterministic assembly that are difficult to address by existing printing schemes, thereby creating engineering opportunities in areas requiring the heterogeneous integration of diverse materials such as curvilinear electronics and MicroLED displays. [ABSTRACT FROM AUTHOR]

Tunable and reversible dry adhesion has attracted much attention in academia and industry due to its wide applications ranging from releasable joints to stamps for transfer printing. Here, a simple yet robust magnetically actuated, aphid-inspired design of an elastomeric surface that provides rapidly tunable and highly reversible adhesion strength is reported. The magnetically actuated adhesive features open reservoirs filled with magnetic particles and encapsulated by a thin surface membrane, which can be deformed in a controlled manner via the magnetic field, thus, to tune the adhesion. The combination of the rate dependent effect and magnetic actuation of the thin surface membrane offers continuously tunable adhesion with a great switchability and a quick response. Experimental and theoretical studies reveal the underlying physics and provide design guidelines to optimize geometries for the broad control of adhesion. Demonstrations of this concept in stamps for transfer printing of silicon wafers in air and in a vacuum with a selective and programmable mode illustrate the capabilities for deterministic assembly and the potential in the semiconductor industry.