This paper presents a lumped perturbation observer-based robust control method using an extended multiple sliding surface for a system with matched and unmatched uncertainties. The fundamental methodology is to apply the multiple surfaces to approximate the unknown lumped perturbations simultaneously influencing on a nonlinear single input–single output (SISO) system. Subsequently, a robust controller, based on the proposed multi-surface and the approximated values, is designed to highly improve the control performance of the system. A general stability of the lumped perturbation observer and closed-loop control system is obtained through the Lyapunov theory. Results of a numerical simulation of an illustrative example demonstrate the soundness of the proposed algorithm.

Toward human is always one of the critical missions for any cyber physical system (CPS). Autonomous robots perceive embarrassing behavior when treating humans as conventional obstacles. In the context of flexible manufacturing or intelligent production, smart CPSs have an important role, since they contributes to the achievement of higher productivity and greater efficiency. In this paper, for intelligent human-machine interaction, a novel approach to safety, comfortability, and anti-collision using the four strategies of emergency break (EMB), slow-down break (SLB), slow-down break then emergency break (SLEMB), and emergency break then emergency break (EM2B) based on visual computation is presented. First, a dynamic model of whole CPS consisting of a vehicle’s body and freight was established. To guarantee comfortable motion and social collaboration, an interactive framework that includes human information was integrated in order to adjust the proper actions of the robot. For the actively and highly computational method, fusing data from both sensing modules and digital cameras provides an efficient technique to estimate a human’s pose and launch reasonable behavior for the movement of the robot. Later, for more intelligent and adaptive performance, a switching mechanism considering the human state was introduced. Based on the results of computer-based simulation and experiments, our approach is valuable for socially human-aware navigation in front of humans with respect to actively safe constraints. The contributions of this work are summarized as follows: (i) dynamical analysis, including the smooth profiles, was studied to suppress residual vibration; (ii) vision-based computation of reaching humans due to the socially interactive model was implemented; and (iii) the switching mechanism provides an alternative method for choosing the proper solution.

Integration of distributed generators (DGs) into a distribution network (DN) can cause coordination challenges of overcurrent relays (OCRs) because of different fault-current contributions of DGs as well as the directional change in fault currents. Therefore, the OCRs should be properly coordinated to maintain their adaptability and scalability to protect the DG-integrated distribution network. In this study, an adaptive and scalable protection coordination (ASPC) approach has been developed for the OCRs in a DG-contained distribution network based on two implementation stages. At the first stage, the reliability improvement of fault-current calculation results is performed by determining the min-max confidence interval of fault current for each different fault type, which is the basis for properly selecting tripping and pick-up thresholds of definite-time and inverse-time OC functions in the same OCR. At the second stage, optimization algorithms are used for calculating protection-curve coefficients and Time-Dial Setting (TDS) multiplier for the inverse-time OC functions in the OCR. A real 22 kV DG-integrated distribution network which is simulated by ETAP software is considered a reliable test-bed to validate the proposed ASPC system of OCRs in the multiple-DG-contained distribution network. In addition, the coordination results of OCRs can be obtained by three common optimization algorithms, Particle Swarm Optimization (PSO), Gravitational Search Algorithm (GSA), and Genetic Algorithm (GA). These relay coordination results have shown an effective protection combination of the definite-time OC functions (50P and 50G) and the inverse-time OC functions (51P and 51G) in the same OCR to get the adaptable and scalable DN protection system.

The supervision and feeding of grazing livestock are always difficult missions. Since animals act based on habits, the real-time monitoring data logger has become an indispensable instrument to assist farmers in recognizing the status of livestock. Position-tracked and acoustic monitoring have become commonplace as two of the best methods to characterize feeding performance in ruminants. Previously, the existing methods were limited to desktop computers and lacked a sound-collecting function. These restrictions impacted the late interventions from feeders and required a large-sized data memory. In this work, an open-source framework for a data collector that autonomously captures the health information of farm animals is introduced. In this portable hardware, a Wireless Location Acoustic Sensing System (WiLASS) is integrated to infer the health status through the activities and abnormal phenomena of farming livestock via chew–bite sound identification. WiLASS involves the open modules of ESP32-WROOM, GPS NEO-6M, ADXL335 accelerometer, GY-MAX4466 amplifier, temperature sensors, and other signal processing circuits. By means of wireless communication, the ESP32-WROOM Thing micro-processor offers high speed transmission, standard protocol, and low power consumption. Data are transferred in a real-time manner from the attached sensing modules to a digital server for further analysis. The module of GPS NEO-6M Thing brings about fast tracking, high precision, and a strong signal, which is suitable for highland applications. Some computations are incorporated into the accelerometer to estimate directional movement and vibration. The GY-MAX4466 Thing plays the role of microphone, which is used to store environmental sound. To ensure the quality of auditory data, they are recorded at a minimum sampling frequency of 10 KHz and at a 12-bit resolution. Moreover, a mobile software in pocket devices is implemented to provide extended mobility and social convenience. Converging with a cloud-based server, the multi-Thing portable platform can provide access to simultaneously supervise. Message Queuing Telemetry Transport (MQTT) protocol with low bandwidth, high reliability, and bi-direction, and which is appropriate for most operating systemsOS, is embedded into the system to prevent data loss. From the experimental results, the feasibility, effectiveness, and correctness of our approach are verified. Under the changes of climate, the proposed framework not only supports the improvement of farming techniques, but also provides a high-quality alternative for poor rural areas because of its low cost and its ability to carry out a proper policy for each species.

Conventionally, software-based motion controllers are used to execute many automation systems in the industry. Most of these controller reveal several drawbacks such as large accumulated error, does not guarantee real-time characteristics when generating motion profile based on software. In this paper, the implementation of embeded motion controller for many applications is presented. ARM Cortex M4 is designed in this controller to handle the communication between host PC and controller. To enhance the high performance of generating trajectory path, hardware-based motion chipset is integrated into the controller. Experimental platform of 2-D delta robot is driven by proposed controller to show the pick and place operations. Several results are carried out to validate the effectiveness and feasibility.

In the domain of field robotic system, it must deal with several challenges during both design and development durations. This study aims to investigate the whole design of robotic system for the internal inspection of tube. Firstly, the robot configuration is launched to identify the physical dimensions. Owing to the size of tube and the curved trajectory, the estimated parameters and shape of robot could be known. Also, some thresholds are obtained in this design which allows the range of dimensions. Secondly, the kinematic robot is analyzed to compute the flexible motion. Through theoretical computations, its locomotion could be evaluated directly. To realize our design, thirdly the detailed selection of servo motor is introduced in order to provide the powerful drive. Hence, the result of driving computations is shown due to the practical specifications of motor. Correspondingly, the spring which plays a role as damper, is measured to suppress the required torques. This spring ensures the continuous contact between leg of robot and internal wall of tube. As a result of these evaluations, both computer-based model and real-world model have been experimented. To guarantee the effectiveness and feasibility of our approach, three levels of validations are presented. In the numerical simulation, the virtual environment is established to substantiate the robotic locomotion. For the laboratory validation, the hardware robot is confirmed the working abilities as well as some trial results. Lastly, this robot must be exemplified in the real scene such as factory or site construction. From these achievements, it could be obviously seen that our approach is proper and feasible for many applications.