This article presents a novel distributed attack-immune fault detection and identification observer (AI-FDIO) for the detection and isolation of sensor and actuator faults in multiagent systems that operate under an attack-immune consensus protocol and are subject to input disturbances. The protocol relies solely on relative output information between neighboring agents, directly measured by local sensors. Based on this locally acquired information, the AI-FDIO performs sensor and actuator fault detection without requiring interagent communication, thereby reducing vulnerability to cyberattacks. Traditional observer-based methods typically decouple residuals from control inputs, making them ineffective in detecting sensor faults that directly affect control signals. In contrast, the proposed AI-FDIO can effectively decouple sensor fault indicators from actuator faults and input disturbances—and vice versa—without relying on any prior knowledge of the faults. A systematic design methodology is presented, and simulation studies on transport aircraft with short-period dynamics and two-wheeled self-balancing robots demonstrate the effectiveness and robustness of the proposed AI-FDIO.

The rapid adoption of microservice architectures has spurred research into addressing various challenges in microservice system evolution, such as service deployment and task offloading. While numerous solutions have been proposed by researchers, validating these approaches requires extensive experimentation, including both algorithmic testing and simulations across different Microservice-Based Applications (MBAs). However, current research lacks sufficient physical experimentation, which is essential for evaluating how these solutions perform when deployed on actual computing infrastructure with running microservice instances. This gap exists mainly because conducting physical experiments is complex and costly, primarily due to two barriers: the lack of standardized problem modeling approaches and the absence of suitable experimental platforms. To address these challenges, the Universal Evolution Model (UEM) was proposed that unifies different microservice research problems within a common evolution framework. This model frames research problems as approaches to evolve microservice systems under specific constraints to achieve desired objectives. Based on UEM and the widely-adopted Monitor-Analyze-Plan-Execute over a shared Knowledge (MAPE-K) model, a general Microservice System Evolution Architecture was designed that standardizes experimental processes across diverse research scenarios. Building on these foundations, MicroForge was presented, an open-source experimental platform equipped with tools for accelerating experiments. The platform incorporates RescueService, a carefully curated MBA. Through comprehensive evaluation across various MBAs, the functional effectiveness of MicroForge was validated. Additionally, a practical user guide was provided to facilitate the platform's adoption and utilization.

Water jumping motion extends the robot's movement space and flexibility. However, the jumping performance is influenced by multiple factors such as driving force, rowing trajectory, and robot structure. The interaction force between the robot and water surface is complicated due to water deformation, and the difficulty of the water jumping increases with the robot's scale. This article designs a miniature water jumping robot with rowing driving legs. The hydrodynamic model between driving legs and water is established based on the modified Wagner theory with consideration of water surface deformation. Particularly, the dynamic model of the robot for the whole jumping process is also developed related to multiple factors. Then, the jumping performance is improved by optimizing the energy storage modality, rowing trajectory, and supporting leg shapes through the theoretical analysis and experiments. The fabricated robot weights 91 g, and its length, width, and height are 220, 410, and 95 mm, respectively. The maximum water jumping height and distance are 241 and 965 mm.

The amazing ability of water striders on water surface has attracted many scholars. Especially the flexible driving mechanism enable the driving legs conform to the deformation of the water surface, which effectively improving water striders’ floating ability and stability. However, the current research on water striders has never designed a flexible driven robot prototype like water striders. This paper proposes a new water strider robot that can walk on water surface based on flexible driving mechanism. The robot’s driving legs are designed with flexible materials and possess ellipse-like spatial trajectories like water striders through a limit pin-linkage mechanism. Based on microelement cantilever method, the flexible driving effect was analyzed with different elastic modulus and diameter. It shows that the flexible legs can row at a higher frequency before puncturing the water surface and achieve bigger work in one period compared with the rigid one. At last, the skating experiment of the robot under different stiffness and rowing frequency was carried out. The results verified that the limit frequency of the flexible driving legs and maximum moving speed of the robot are about 41.3% and 36.2% higher than those with rigid legs, respectively. Moreover, a similarity analysis of hydrodynamic characteristic constants reveals that the locomotion of the flexible driving robot is more analogous to the biological water striders than the rigid one.

Aiming at mimicking the jumping locomotion of water striders, a new continuous jumping robot on water is proposed. Compared with the horizontal rowing motion, the jumping capability of water striders is challengeable to imitate, since the impact force on water is easy to cause the sinking of the robot. In this paper, a jumping mechanism based on springs is designed to produce a large thrust for the robot to jump. The shape of supporting legs and center of gravity of the robot are carefully designed so that the robot can jump on the surface continuously and smoothly. Influences of several critical factors, including the area of supporting legs, spring stiffness and jumping angle, on jump performance are analyzed by means of dynamic simulation and experiments. The fabricated robot weighs about 10.2 g and can continuously jump on water with the maximum leap height and length of 120 mm and 410 mm, respectively.

Aiming at mimicking water strider's water-surface locomotion, this study proposes a new miniature surface tension-driven robot. A key feature of this robot is that its actuating legs possess ellipse-like spatial trajectories like water strider by using a cam-link mechanism, and never pierces water surface when rowing. A set of simple models and equations are proposed to analyze the interaction forces between leg and water as well as the critical condition for a leg penetrating a water surface. The final fabricated robot weights about 3.9 g with a load capacity of 5.6 g. By controlling the motions of actuating legs, the robot can freely and stably walk on water with different gaits. The maximum forward and turning speeds of the robot are measured as 16 cm/s and 23 °/s, respectively. Moreover, a similarity analysis with Bond Number and Weber Number reveals that the locomotion of this robot is quite analogous to that of a water strider: surface tension force dominates the lifting force and plays a major role in the propulsion.

ABSTRACT On the basis of hash chain and Lagrange interpolation formula over a finite field, a lightweight micropayment scheme is proposed. Compared with Micali and Rivest's micropayment scheme, the improved scheme achieves three additional properties to ensure it suitable for mobile network. First it reduces the computing burden without digital signature algorithm, which is essential for limited mobile terminal. Second, the user, the merchant, and the bank are all equally involved in the selection of payable checks, which ensure the proposed scheme is fair for all parties. Moreover, the privacy of scheme is also achieved for the computational infeasibility of calculating the inverse of secure one‐way function. The improved micropayment scheme is secure, fair, and efficient, and privacy‐preserving, especially suitable for mobile network. Copyright © 2012 John Wiley & Sons, Ltd.

Significant research have been devoted into the field of multi-robot teleoperation system over Internet. However, the low safety and efficiency due to time delay and complexity between multiple robots and operators prevent the teleoperation technology from developing. Specially, the possible collision between multiple robots has a great effect on the Internet-based multi-operator-multi-robot teleoperation system. In this paper, a task planner based on Petri net theory was proposed to assist multi-operators coordinate multi-robots. The conception of implicit elementary operation and explicit elementary operation were introduced to realize modeling and automatic plan of the system. In the multi-operator multi-robot system built by us, a supervisory controller was designed based on the place invariants not only to lead two operators' manipulation with virtual environment but also to restrict the state of two robots' motion during their work. An experiment via network was carried out to evaluate the validity of the task planner for the medical research of highly dangerous virus such as SARS, bird flu etc. The experimental results show that the safety and efficiency of the system can be improved using the task planner

A closed loop self-calibration method for Delta mechanism and 3-RRR mechanism used in a double parallel haptic device was presented. This approach blocks successively one joint of each parallel mechanism using a simple lockup device and reforms the 3-DOF mechanism to be a 2-DOF one. The parameter errors of the mechanism are identified according to the differences between the sensor output of the redundant chain and nominal model output. Both the condition number and singular value of the error propagation Jacobian are synthesized as a new selection principle of calibration set such that the calibrating process is insensitive to the noise and the calibration precision is increased efficiently. Experiments show that the ratio of maximal error before and after calibrating is 9.6, namely, the setting accuracy of the two mechanisms are increased about 10 times and the error of re-position is less than 0.1 mm and 0.1deg

Time delay over the Internet deteriorates the performance of multi-operator-multi-robot teleoperation system (MOMR). At present, several methods aiming at the problems of the Internet-based multi-telerobot collaboration only depend on the master side. In this paper, a coordinated controller was presented based on the idea of shared control that combined the intelligence of the master side with the slave side. It is composed of three modules, task coordination, motion planning and communication, which can not only increase the efficiency and safety of the system but also relieve the burden and the requirements to the operators. The controller also can cope with the collision between two telerobots in the common environment arising from the time delay. A simulation experiment via an Ethernet local area network (LAN) subject to simulated time delay was carried out to protect the medical staff from highly dangerous virus such as SARS, bird flu etc. And the validity of the coordinated controller was evaluated in the system.