The development of femtosecond lasers has renovated micromachining technology, enabling the microdrilling of transparent materials at high speed. Although effective, this technique is still imperfect because irregular microscopic damage occurs during processing. Several factors in the formation of damage induced by a single laser pulse have been suggested; however, the entire mechanisms of damage formation in the process of drilling are not fully understood. Here we investigated the causes of microscopic damage both by experimentally carrying out laser drilling on chemically strengthened glass samples and by numerically analyzing the propagating stress wave and temperature distribution. We have revealed that the damage at the sidewall and bottom of a generated hole is mainly due to the stress wave, while the damage around the hole entrance is mainly due to relaxation of thermal stress. In particular, we have analyzed these processes quantitatively, demonstrating the time courses of the passage of the stress wave through the material and the temperature distribution generated by the excited electrons. Our analyses are useful in suggesting processing techniques, or suggesting glass materials suitable for laser drilling such as glass with high heat resistance, which may lead to an improvement in the quality of micromachining.

Layer-by-layer manufacturing of composite mechanisms allows fast and cost-effective fabrication of customized robots in millimeter and centimeter scales which is promising for research fields that rely on frequent and numerous physical iterations. Due to the limited number of components that can be directly integrated in composite structures, however, often an assembly step is necessary which diminishes the benefits of this manufacturing method. Inspired by the Japanese craft of cutting (kiri-) paper (-gami), Kirigami, we introduce quasi-2D and highly stretchable functional Kirigami layers for direct integration into the composite mechanisms. Depending on the material and geometrical design; functional Kirigami layers can perform as flat springs, stretchable electronics, sensors or actuators. These components will facilitate the design and manufacturing of composite robots for different applications. To illustrate the effectiveness of these components, we designed and realized a foldable composite inchworm robot with three Kirigami layers serving as actuator, sensor and contact pad with directional friction . We elaborate on the working principle of each layer and report on their combined performance in the robot.

Aerial manipulation is a growing field of research, and multirotors with attached arm manipulator have shown practical utility in contact-based inspection. However, theses coupled platforms limit the pose reachability of the end-effector, which then motivates the development of omni-directional designs for aerial robots. Although the full pose tracking can be achieved by these omni-directional models, the large amount of internal thrust force constrains wrench exertion for forceful manipulation such as valve operation. Thus, in this letter, we harness an articulated aerial robot equipped with thrust vectoring apparatus, which enables not only the omni-directional pose of end-effector, but also the sufficient 6 $^{\circ }$ -of-freedom wrench for valve operation. First, we develop a joint configuration strategy for this articulated model to ensure sufficient torque to turn valves. Then, we present control and motion planning methods for exerting appropriate wrench while following a manipulation trajectory. Comprehensive experiments that involves various valve directions are evaluated in this work, demonstrating the feasibility of our methods to exert forceful wrench. To the best of our knowledge, this letter is the first to achieve the operation of real industrial valve with real torque scale.