Supervisory Computer Research Articles

EMARLIN: Distributed Coordinated Adaptive Traffic Signal Control with Topology-Embedding Propagation

In this paper, we examine the practical problem of minimizing the delay in traffic networks that are controlled at each intersection independently, without a centralized supervisory computer and with limited communication bandwidth. We find that existing learning algorithms have lackluster performance or are too computationally complex to be implemented in the field. Instead, we introduce a simple yet efficient and effective approach using multi-agent reinforcement learning (MARL) that applies the Deep Q-Network (DQN) learning algorithm in a fully decentralized setting. First, we decouple the DQN into per-intersection Q-networks and then transmit the output of each Q-network’s hidden layer to its intersection neighbors. We show that our method is computationally efficient compared with other MARL methods, with minimal additional overhead compared with a naive isolated learning approach with no communication. This property enables our method to be implemented in real-world scenarios with less computation power. Finally, we conduct experiments for both synthetic and real-world scenarios and show that our method achieves better performance in minimizing intersection delay than other methods.

Intelligent Embedded Systems Platform for Vehicular Cyber-Physical Systems

Intelligent vehicular cyber-physical systems (ICPSs) increase the reliability, efficiency and adaptability of urban mobility systems. Notably, ICPSs enable autonomous transportation in smart cities, exemplified by the emerging fields of self-driving cars and advanced air mobility. Nonetheless, the deployment of ICPSs raises legitimate concerns surrounding safety assurance, cybersecurity threats, communication reliability, and data management. Addressing these issues often necessitates specialised platforms to cater to the heterogeneity and complexity of ICPSs. To address this challenge, this paper presents a comprehensive CPS to explore, develop and test ICPSs and intelligent vehicular algorithms. A customisable embedded system is realised using a field programmable gate array, which is connected to a supervisory computer to enable networked operations and support advanced multi-agent algorithms. The platform remains compatible with multiple vehicular sensors, communication protocols and human–machine interfaces, essential for a vehicle to perceive its surroundings, communicate with collaborative systems, and interact with its occupants. The proposed CPS thereby offers a practical resource to advance ICPS development, comprehension, and experimentation in both educational and research settings. By bridging the gap between theory and practice, this tool empowers users to overcome the complexities of ICPSs and contribute to the emerging fields of autonomous transportation and intelligent vehicular systems.

Development and verification of integrated photoelectric system for noncontact detection of pavement ponding and freezing

The ponding water and ice on the road surface can cause degradation of skid resistance that seriously affects driving safety. In order to accurately detect road surface conditions, an integrated photoelectric system was developed composed of an infrared light-emitting diode and a phototransistor. Typical asphalt pavements such as AC-13, SMA-13, and OGFC-13 were selected to simulate four road surface conditions: dry, wet, ponding water, and ice. The voltage intervals for dry and wet surface conditions were proposed by the light intensity method. The functional relationships were established between the depth of ponding and the output voltage, the thickness of ice, and the output voltage, respectively. The noncontact detection system for pavement ponding and freezing was developed by the design of the hardware of real-time controller, the software of supervisory computer, and the shell of entire system. Then the system was verified in the field conditions. According to the test results, there was a good linear relationship between the ponding depth and the output voltage, while there was a quadratic parabolic relationship between the ice thickness and the output voltage. The detecting accuracy was 91.67% for the dry and wet surface conditions. The detecting errors of ponding depth for three different types of pavement surface were 0.248, 0.168, and 0.189, respectively; the detecting errors of the ice thickness for three different types of pavement surface were 0.219, 0.261, and 0.326, respectively. The errors were within a reasonable range, and the detecting accuracy of ponding depth is higher than that of ice thickness.

Practical Implementation of the System of Feeder Diagnostics of Single-Phase Earth Faults with Online Distributed Data Collection

Single-phase earth faults are one of the main problem of the distribution electrical networks with voltage 6 - 35 kV with isolated neutral. Single-phase earth fault is one of the reasons decrease of the power quality and the reliability of power supply. The paper presents the theoretical base of the monitoring parameters selection during the single-phase earth fault process and its practical implementation as an installed system at a power substation with a 110/10 kV level voltage. The hardware part of the feeder monitoring system allows implementing the determination of feeder with fault and the phase of this feeder with fault without the need to switch off of the feeders. The software part of the system allows for ongoing monitoring of feeders with built-in alarm and viewing the event archive on the supervisor computer.

An efficient data routing scheme for multi-patient monitoring in a biomedical sensor network through energy equalization strategy

Biomedical sensor networks find wide applications in human health monitoring. In such applications, routing strategies in the sensor nodes play a key role towards energy efficiency of the overall system. In this work, we present a new data routing scheme, which is based on residual energy in a node and equalization (named EEQ) among the neighbours to achieve enhanced average node lifetime under short range monitoring scenario. The scheme was hardware implemented using 12 number of indigenous ATmega328 based static biomedical sensor nodes (BSN) arranged in a grid matrix spread over a floor area of 564 sqm. The objective was to collect short duration electrocardiogram and photoplethysmogram signals from human subjects in a local supervisory computer placed outside the grid. Under simulation platform using 100 BSNs with first order radio model, it was found that the average node lifetime was enhanced by 17% against without EEQ evaluated over 10,000 consecutive data collection sessions. The proposed scheme can be useful for providing low cost solution in healthcare settings in developing nations like India.

Hierarchical control of aluminum smelter loads for primary frequency support considering control cost

Providing ancillary service with controllable loads has drawn increasing attention from academia and industry. This paper proposes a hierarchical control strategy for aluminum smelter loads (ASLs), a typical controllable load, to provide primary support in a cost-efficient way. At the higher level, the supervisory computer in the aluminum smelting plant (ASP) estimates the available power of ASLs and allocates the contracted reserve to ASLs by optimization. At the lower level, within the allocated reserve from the higher level, ASLs respond to frequency deviations automatically by changing their power consumption, which is implemented by a local control scheme based on a novel DC current control (DCC) scheme and a dynamic frequency threshold (DFT) approach. Compared with the existing PI-based DCC, the novel DCC employs model predictive control (MPC) to improve its transient performance. The DFT approach can avoid ASLs responding to frequency deviations in the serious anode effects (AE) situations. Case studies are carried out based on the data of an actual ASP. The results show that the hierarchically controlled ASLs can reduce the frequency drop with lower control cost and reduce the regulation dependency on the generation side. Besides, the high performance of the MPC-based DCC and the effectiveness of the DFT approach are also demonstrated.

An Intelligent and Power Efficient Biomedical Sensor Node for Wireless Cardiovascular Health Monitoring

Wireless human health monitoring using different techniques has been a popular research area in the last few decades. In this paper, we describe the development of a biomedical sensor node (BSN) for short-range monitoring of static cardiovascular patients using a supervisory computer. In particular, the present research focuses on developing (a) an intelligent hybrid routing algorithm which takes care of intermediate node(s) failure condition; (b) improved packet delivery ratio with the reliability and efficient use of BSN’s battery power. A data compression algorithm in the BSNs further enhanced the communication channel efficiency. With 15 BSNs hardware implemented and tested over a floor area of 93 m2 to collect electrocardiogram and finger pulse signals, we achieved average packet reception accuracy over 98.45% taken cumulatively over 200 trails, along with a latency of 1.58 s per data packet with three faulty BSNs and maximum number of allowable transmission attempts in each hop. A simulation study with the first-order radio model, using 100 BSNs under nine faulty nodes and worst-case scenario, yielded a node power consumption of 3.49 mW per packet and a latency of 22 s per data packet. The performance results are superior to those of similar published works on wireless biomedical health monitoring using wireless sensor networks. The developed system can provide a low-cost solution for patient monitoring at indoor hospital wards in developing nations like India.

Dynamic Optimization of Data Packet-based Communication for PLC Visual Monitoring

This paper presents a dynamic optimization solution for the data packet-based communication of programmable logic controller (PLC) visual monitoring, and the objective is to improve the communication efficiency between a supervisory computer and field PLCs in consideration of the network communication performance, such as network bandwidth, packet loss or retransmission rate, and human response delay. A nonlinear optimization model with constraints is formulated and solved analytically to obtain the minimized transmission time. Experimental results demonstrate that the proposed dynamic optimization can solve the practical industry problem in an efficient and effective manner, and it can provide useful guidance for the data packet-based communication setting of networked control systems.

Upgrade of the Ball and Plate Laboratory Model

This paper deals with the overall hardware and software upgrade of the Ball&Plate laboratory model used at the Center of Modern Control Techniques and Industrial Informatics (CMCT&II) at Department of Cybernetics and Artificial Intelligence (DCAI), FEEI, TUKE. Reasons for upgrading the model are described, along with the proposed solution. Design and construction of new control hardware for the model is presented. The paper next describes the implementation of program modules for controlling the position of the ball on the plate at level of the MicroController Unit (MCU) and the supervisor computer. Several approaches of image recognition with the purpose to obtain ball position are tested and compared. Finally, the paper presents the model-based design and verification of a PSD control algorithm for the Ball&Plate model. After the upgrade, the model can be used at the CMCT&II for both research and teaching purposes, with the emphasis on the implementation of applications with high demands on hardware performance, where higher sampling rates of the control algorithms are required.

Design of a Prototype for a Modular Mobile Robotic Platform

This paper deals with the design and implementation of a prototype for a modular mobile robotic platform for the universal use in both research and teaching activities. It describes the development of a mobile robot skeleton which is low-cost and easy to produce by means of 3D printing. It next deals with prototyping the robot’s hardware components, focusing on the development of the robot’s main control unit and implementation of communication interfaces. The concept of multiple sensor modules connectable to the robot’s top side is also described. The paper next concentrates on the implementation of program modules at the level of MicroController Unit (MCU) on the control board, including the management of peripheral components as well as the implementation of control algorithms and communication protocols. Last but not least, it deals with the development of software modules for the MCUs on individual sensor modules and with the implementation of services for robot control at the level of the supervisor computer using the Robotic Operation System (ROS) communication system.

Mobile Robots Navigation Modeling in Known 2d Environment Based on Petri Nets

AbstractThe paper deals with supervised robot navigation in known environments. The navigation task is divided into two parts, where one part of the navigation is done by the supervisor system i.e. the system sets the vector marks on the salient edges of the virtual environment map and guides the robot to reach these marks. Mobile robots have to perform a specific task according to the given paths and solve the local obstacles avoidance individually. The salient point’s detection, vector mark estimation and optimal path calculation are done on the supervisor computer using colored Petri nets. The proposed approach was extended to simulate a flexible manufacturing system consisting of swarm of 17 robots, 17 - warehouses and 17 - manufacturing places. Our experimental investigation showed that simulated mobile robots with proposed supervision system were efficiently moving on the planned path.

Dependability enhancing mechanisms for integrated clinical environments

In this article, we present a set of lightweight mechanisms to enhance the dependability of a safety-critical real-time distributed system referred to as an integrated clinical environment (ICE). In an ICE, medical devices are interconnected and work together with the help of a supervisory computer system to enhance patient safety during clinical operations. Inevitably, there are strong dependability requirements on the ICE. We introduce a set of mechanisms that essentially make the supervisor component a trusted computing base, which can withstand common hardware failures and malicious attacks. The mechanisms rely on the replication of the supervisor component and employ only one input-exchange phase into the critical path of the operation of the ICE. Our analysis shows that the runtime latency overhead is much lower than that of traditional approaches.

Implementation and performance evaluation of advance metering infrastructure for Borneo-Wide Power Grid

In this paper, a supervisory computer network for Borneo-Wide Power Grid system have been proposed and implemented, which includes a renewable power generation and advanced metering infrastructure. An Internet-based communication network running on multi-protocol label switching (MPLS) has been implemented for a smart power grid, with the addition of the renewable energy monitoring system. The centralized supervisory control and data acquisition systems (SCADA) are replaced by a wide area monitoring system(WAMS) comprising of a phasor measurement unit (PMU). The implemented communication network used advanced metering infrastructure that operates on worldwide interoperability for microwave access (WiMAX), wireless fidelity (Wi-Fi) and low power Wi-Fi, which are proposed for the distribution systems of Sarawak Energy. The proposed wide area network (WAN) is simulated using OPNET Modeler and the results are compared with the existing WAN used by Sarawak Energy.

Multi-Bus Fiber Sensor Protection Network Operation With Robustness Analysis

This paper proposes a multi-bus fiber-optic sensor network, which could multiplex different types of fiber sensors, locate the failure position, and recover the sensing services of sensors in a network immediately and automatically to keep them working without being interrupted. It is composed of master and slave nodes, as well as working and backup fibers connecting them. We introduce the operation of the network and two light source distributions by explaining the internal structures of the master and slave nodes along with the sensor protection and the fault location process. Then, we analyze the probability distribution of working status for both distributions and propose a quantitative evaluation criterion called weighted average robustness for the robustness analysis of any fiber sensor network. Meanwhile, this paper demonstrates its feasibility by multiplexing three fiber sensor systems: a distributed fiber-optic vibration sensor based on dual Mach-Zehnder interferometer architecture; an optical frequency domain reflectometry sensor; and three Fiber Bragg Grating sensors in this network at the same time detecting different parameters. We test the performance of the network in three scenarios by fabricating failures of the sensing and backup fibers intentionally to prove the feasibility of the structure. Furthermore, all the status of the network will be uploaded to the human-computer interface of supervisory computer by the master processor through USB in real time. Operators can also control the network through the interface remotely.

Output power stability of a HCN laser using a stepping motor for the EAST interferometer system

The HCN laser on EAST is a continuous wave glow discharge laser with 3.4 m cavity length and 120 mW power output at 337 μ m wavelength. Without a temperature-controlled system, the cavity length of the laser is very sensitive to the environmental temperature. An external power feedback control system is applied on the HCN laser to stabilize the laser output power. The feedback system is composed of a stepping motor, a PLC, a supervisory computer, and the corresponding control program. One step distance of the stepping motor is 1 μ m and the time response is 0.5 s. Based on the power feedback control system, a stable discharge for the HCN laser is obtained more than eight hours, which satisfies the EAST experiment.

Tracing current-voltage curve of solar panel Based on LabVIEW Arduino Interfacing

This study describes a low cost system to measure current and power-voltage characteristics of photovoltaic (PV) silicon solar panel under natural conditions based on LabVIEW software. The desired parameters of PV panel including fill factor, max power, short-circuit current, open-circuit voltage are calculated. The characteristics of the solar panel have been drawn quickly using the MOSFET as an electronic load, which is controlled by means of a suitable gate-source voltage. The new development of this work includes the Arduino to acquire the values of current and voltage from the solar panel under test and transfer it to a supervisory computer. All details of the electronic circuit are shown in this paper and experimental results obtained are presented.

Design and Realization of Management and Control System in Tobacco Factory Warehouse Based on VC6

The paper proposed the management and monitoring system of automatic tridimensional warehouse based on network communication, the main characters and realization of communication program developing with VC6 are expounded in the paper based on industrial Ethernet communication. the system is divided into the automated warehouse management and control system functional modules. And the communication model between the supervisor computer and the ARM2440 is presented. Experimental results show that the design has lower cost and achieves system integration management and control function.

Design and Realization of Management and Control System of Warehouse Based on VC6

The designing and realizing methods of network communication of the management and monitoring system of automatic tridimensional warehouse and proposed,the the main characters and the way of communication program developing with VC6 are expounded based on industrial Ethernet communication.Use the the ARM2440 control panel, the system is divided into the automated warehouse management and control system functional modules.And the Ethernet-based communication model used between the supervisor computer and the ARM2440 is presented. The realization and utilization of the design are described. The information and software integration of the system are illuminated, too. The design has lower cost and achieves system integration of management and control of an AS/RS by common devices and technology.

Design and Implementation of Yarn Tension Measurement System during Weft Insertion on Air-Jet Loom

Yarn tension during weft insertion is one of important factors which affect fabric properties. In air jet loom, many components have an influence on yarn tension, such as clamp, main nozzle, sub nozzle, brake, and the drum. In this paper, a measurement system for yarn tension experiment which based on a 32-bit Cortex-M3 embedded processor was designed and implemented. The system can control components at fixed time interval which is set by a supervisory computer, acquire yarn tension converted by a contacted electromagnetic induction tension sensor, and then transmit tension data to software system by Ethernet module. An experiment is conducted for research character of yarn tension driven by air flow. The experiment results indicate that the nozzle pressure and yarn diameter play an important role in yarn tension during weft insertion on air-jet loom. Besides, the delay of magnetic value is also considered under different nozzle pressure.

Oscillation modal analysis from ambient synchrophasor data using distributed frequency domain optimization

This paper provides a distributed frequency domain algorithm for real-time modal estimation of large power systems using ambient synchrophasor data. By dividing the computation between a supervisory central computer and local optimizations at the substation level, the algorithm efficiently estimates multiple dominant mode frequencies, damping ratios and mode shapes from wide-area power system measurements. The algorithm, called distributed frequency domain optimization, is tested on known test systems and archived real power system data from eastern and western power systems.