When an octopus grasps something, the rigidity of its tentacle can change greatly, which allowing for unlimited freedom, agility, and precision. Inspired by this, a three-finger flexible bionic robot gripper was designed for apple picking. First, a flexible chamber finger was designed to drive the gripper finger to elongate, shorten, and bend, which works through a process of inflating and deflating. Further, we proposed a three-finger mode to achieve two kinds of motion states: grasping and relaxing, by simulating the movement of an octopus grasping at something. In this paper, we evaluated the bending property of the designed flexible bionic gripper through an apple grasping experiment. The experimental results show that the 100.0 g bionic gripper can load an apple with a weight of 246.5~350.0 g and a diameter of 69.0~99.0 mm, and the grasping success rate is 100%. It has a good grasping performance. Compared to other soft grippers, the proposed bionic flexible gripper has the advantages of being lightweight, and having good cushioning, low driving air pressure, and a strong grasping force.

Realizing the anisotropic deep trenching of GaN without surface damage is essential for the fabrication of GaN-based devices. However, traditional dry etching technologies introduce irreversible damage to GaN and degrade the performance of the device. In this paper, we demonstrate a damage-free, rapid metal-assisted chemical etching (MacEtch) method and perform an anisotropic, deep trenching of a GaN array. Regular GaN microarrays are fabricated based on the proposed method, in which CuSO4 and HF are adopted as etchants while ultraviolet light and Ni/Ag mask are applied to catalyze the etching process of GaN, reaching an etching rate of 100 nm/min. We comprehensively explore the etching mechanism by adopting three different patterns, comparing a Ni/Ag mask with a SiN mask, and adjusting the etchant proportion. Under the catalytic role of Ni/Ag, the GaN etching rate nearby the metal mask is much faster than that of other parts, which contributes to the formation of deep trenches. Furthermore, an optimized etchant is studied to restrain the disorder accumulation of excessive Cu particles and guarantee a continuous etching result. Notably, our work presents a novel low-cost MacEtch method to achieve GaN deep etching at room temperature, which may promote the evolution of GaN-based device fabrication.

No abstract

No abstract