Summary Liquid metal has demonstrated an enormous potential for developing soft functional devices and machines. However, current liquid metal enabled machines suffer from several issues, such as the requirement of a liquid environment, generation of weak actuating forces, and insufficient maneuverability. To overcome these restrictions, here, a motor is developed based on the electrical actuation of liquid metal droplets without the need for conventional electromagnets. The approach is distinguished by (1) the encapsulation of electrolyte and multiple liquid metal droplets within an enclosed system, and (2) the creation of stable and continuous torque outside a liquid environment. In addition, a liquid metal electrical brush is introduced to operate the motor with low friction and low wear. The unique driving mechanism endows the motor with several advantages, including low friction, no sparking, low noise, versatile working environment, and being built from soft materials that could offer new opportunities for developing soft robotics.

The presence of microdomes can significantly increase the surface roughness, contact area, and deformability of materials, which have been adopted in many fields including microfluidics, wearable devices, and microanalysis systems. However, the shape of liquid metal (LM) droplet is defined by the density and surface energy, which has very limited room to tune. In this work, a simple, low‐cost method to effectively control the profile of LM using the masked amalgamation is presented. The LM amalgamates the masked copper surface to create the complex microdomes with various aspect ratios, sizes, profiles, and structures. The concave dome replicated from the LM mold has been demonstrated to enhance the microfluidic mixing performance. With a pattern transfer technique, the microconvex domes can be patterned on the surface of stretchable conductive composites to develop a flexible and sensitive pressure sensor. This sensor exhibits a fast response time, a wide working range, and an enhanced sensitivity for detecting small strains. As such, the fabricated microdomes exhibit a great potential to enable the fabrication of high‐performance sensors, microfluidic platforms, and micro total analysis systems.

Engines are systems that convert different forms of energy into mechanical motion. The increasing demand in driving small scale machines for applications in medical auxiliary devices, robotics and microfluidics has engendered the urgent need of developing miniaturized engines that are easy to fabricate, simple to operate and maintain, robust, and highly efficient. To date, mechanisms adopting piezoelectric, [1] electromagnetic, [2]

No abstract

Harnessing natural-based renewable molecular resources to construct functional synthetic green polymers is a promising research frontier at the interface of sustainable/green chemistry, polymer chemistry and nanobiotechnology. As natural glycoprotein mimics/analogues and biocompatible building blocks of nanobiomaterials, synthetic functional glycopolypeptides and their structural/functional analogues have attracted great attentions in recent years. This mini-perspective article reviewed current synthetic strategies and methods of glycopolypeptides and their analogues. The pros and cons of the synthesis protocols were discussed, moreover, possible future perspectives in this field were also stated.