In this note, the leader-following consensus problem is considered for a class of second-order nonlinear multiagent systems, where communication topology switching. view that Lipschitz constants terms are unknown, adaptive control strategy adopted. Using back-stepping technique, new protocol proposed. It noted global information, including eigenvalues Laplacian matrix, not used in design. proven practical can be reached by given scheme. Finally, we present numerical example to show...

The underwater structured light vision system has the characteristics of a large amount information, high measurement accuracy, and good robustness, which attracted attention researchers is widely used in 3-D measurement. In this article, state-of-the-art techniques are comprehensively summarized, provides valuable guidance for relevant researchers. First, systems classified introduced, their advantages disadvantages analyzed. Then, calibration methods including camera calibration, laser...

Abstract Photothermal catalysis is one of the most promising green catalytic technologies, while distinguishing effects hot electrons and local heating remains challenging. Herein, we reported that actual reaction temperature photothermal ammonia synthesis over carbon‐supported Ru catalyst can be measured based on Le Chatelier′s principle, enabling hot‐electron contribution to quantified. By excluding effects, established activation energy via was much lower than thermocatalysis (54.9 vs....

The three dimensional (3D) perception of the low-light underwater environment has always been a major challenge which greatly limits operations. In this paper, an active vision measurement system based on binocular structured light is designed to achieve high precision 3D reconstruction. Firstly, fusion technology camera and laser addresses optical attenuation feature sparsity. Then, in order avoid huge inertia caused by overall movement system, scanner mirror-galvanometer used accomplish...

This paper addresses the novel design of an underwater manipulator with a lightweight multilink structure and its free-floating autonomous operation. The concept reduces coupling between vehicle efficiently, even in case where weight air is not significantly greater than weight. specific implementation mechanical elaborated. Moreover, closed-loop control system based on binocular vision proposed for manipulation. In end, experimental results demonstrate that conceived can accomplish...

This brief presents the real-time dynamic Dubins-Helix (RDDH) method for trajectory smoothing, which consists of generation and pitch angle smoothing. The generated 3-D is called RDDH trajectory. On one hand, projection on horizontal plane partially by Dubins path planner such that curvature radius constraint satisfied. other Helix curve constructed to satisfy constraint, even in case initial final poses are close. Furthermore, analyzing relationship between parameters effectiveness...

Probing nanostructures (e.g., nanoelectronics) requires accurate and precise nanopositioning. Furthermore, since measuring I-V data from dc to GHz typically takes more than a minute, tolerance for position drift is stringent during the collection process. This paper reports closed-loop controlled nanomanipulation system operation inside scanning electron microscope. A new sensing method with low power consumption used achieve nanometer resolution effective heat dissipation management. For...

Abstract Efficient propulsion has been a central focus of research in the field biomimetic underwater vehicles. Compared to prevalent fish-like reciprocating flapping mode, sperm-like helical mode features higher efficiency and superior performance high-viscosity environments. Based on previously developed sperm-inspired robot, this paper focuses its dynamic modeling depth control research. The robot is analyzed by resistance-theory-based force analysis, followed application Kirchhoff rod...

This paper studies the mean square consensus of discrete-time linear time-invariant multi-agent systems with communication noises. A distributed protocol, which is composed agent's own state feedback and relative states between agent its neighbours, proposed. time-varying gain a[k] applied to attenuate effect noises inherits in inaccurate measurement neighbours. polynomial, namely 'parameter polynomial', constructed. And coefficients are parameters vector proposed protocol. It turns out that...

Seam feature point acquisition is the premise of intelligent welding process such as initial guiding and seam tracking. However, conventional methods based on geometric have shortcomings poor flexibility robustness. In this article, a method efficient convolution operator (ECO) particle filter (PF) proposed, which could be applied to different weld types achieve fast accurate even under interference arc light spatter noises. First, structured vision sensor developed acquire image. Second,...

The teaching programming mode and offline of welding robot are essential parts in today's manufacturing industry. However, these modes can't meet the automation requirements adaptive ability robot. To achieve 3D path acquisition weld seam for autonomous programming, a fast accurate extraction method is proposed based on monocular structured light sensor. In this method, gray code phase-shift raster images projected to workpiece, coordinates calculated by collecting workpiece with patterns....

The paper presents a novel method for mobile robot localization using visual appearance features. A multidimensional histogram is used to describe the global features of an image such as colors, edge density, gradient magnitude, textures and so on. matching histograms determines location robot. has been evaluated in indoor environment, system correctly 82.9% input scene images.

Embryo vitrification is an essential cryopreservation technique in IVF (in vitro fertilization) clinics. Vitrification involves pick-and-place of embryo multiple types cryoprotectant solutions for processing before placing the on a straw liquid nitrogen. Manual operation and existing robotic are only capable aspirating one at time processing; thus, other embryos kept culture dish microscope stage tens minutes, which detrimental to development potential embryos. In order minimize total time,...

This paper investigates the event-triggered leader-following consensus problem for a class of multiple mechanical systems with switched dynamics. Based on graph theory, Lyapunov stability backstepping technique and control an protocol is proposed considered systems. It proved that practical can be achieved by protocol. Meanwhile, to exclude Zeno behaviour, positive lower bound inter-event intervals given. Finally, we provide numerical simulation illustrate effectiveness given

Due to the complex mechanism and fabrication process of flexible materials, it remains extremely challenging for a robotic fish achieve fast efficient locomotion. In this article, taking advantage passive bending energy storage properties we propose an untethered with multiple joints high performance low Cost Transport (COT). First, combining rigid links compact tail simple structure is proposed. Next, pseudo-rigid body theory applied analyze deformation joints, full-state dynamic model...

In this paper, a heading controller based on self-tuning fuzzy strategy for robotic dolphin is proposed to improve control accuracy and stability. The structure of the introduced turning motion analysed. analytic model indicates that joint angle can be employed control. This non-linear prevents successful application traditional model-based controllers. A realize in our work. It should mentioned suffers from distinguished steady-state error, due fact range relatively large controller's...

Cell morphology plays an important role in maintaining normal cellular functions. Existing techniques for cell measurement, such as confocal imaging and atomic force microscopy, have the limitations of photobleaching incompatibility integration with other manipulation instruments. This paper reports a robotic system that is capable measuring changes morphologies. capability enabled by several key including recognition, determination contact points on cell, two vision-based detection methods...

Abstract Photothermal catalysis is one of the most promising green catalytic technologies, while distinguishing effects hot electrons and local heating remains challenging. Herein, we reported that actual reaction temperature photothermal ammonia synthesis over carbon‐supported Ru catalyst can be measured based on Le Chatelier′s principle, enabling hot‐electron contribution to quantified. By excluding effects, established activation energy via was much lower than thermocatalysis (54.9 vs....

In nature, fish can achieve efficient swimming through vortex control, which is also a crucial factor in the propulsion of biomimetic robotic fish. Existing analytical models generally do not consider vortices. addition, numerical methods for solving fluid dynamics are complex and computationally intensive. this article, based on discrete method (DVM), point circulation caused by tail oscillation calculated an accurate dynamic model established. Specifically, single-joint fish, hydrodynamic...

Underwater collision-free navigation and dense reconstruction are essential for marine refined exploration. However, existing passive vision-based methods difficult to apply in low-light weak-feature underwater environments. In this article, a more adaptable three-dimensional (3-D) mapping robotic system based on self-designed scanning binocular structured light (BSL), named ROV-Scanner, is developed address challenge. First, the measurement principle refraction model ensures its high...