Wireless Network Design for Control Systems: A Survey (1708.07353v1)

Abstract: Wireless networked control systems (WNCS) are composed of spatially distributed sensors, actuators, and con- trollers communicating through wireless networks instead of conventional point-to-point wired connections. Due to their main benefits in the reduction of deployment and maintenance costs, large flexibility and possible enhancement of safety, WNCS are becoming a fundamental infrastructure technology for critical control systems in automotive electrical systems, avionics control systems, building management systems, and industrial automation systems. The main challenge in WNCS is to jointly design the communication and control systems considering their tight interaction to improve the control performance and the network lifetime. In this survey, we make an exhaustive review of the literature on wireless network design and optimization for WNCS. First, we discuss what we call the critical interactive variables including sampling period, message delay, message dropout, and network energy consumption. The mutual effects of these communication and control variables motivate their joint tuning. We discuss the effect of controllable wireless network parameters at all layers of the communication protocols on the probability distribution of these interactive variables. We also review the current wireless network standardization for WNCS and their corresponding methodology for adapting the network parameters. Moreover, we discuss the analysis and design of control systems taking into account the effect of the interactive variables on the control system performance. Finally, we present the state-of-the-art wireless network design and optimization for WNCS, while highlighting the tradeoff between the achievable performance and complexity of various approaches. We conclude the survey by highlighting major research issues and identifying future research directions.

• The paper provides an exhaustive review of WNCS design, evaluating trade-offs between delay, message dropout, and energy consumption.
• It analyzes various wireless protocols like IEEE 802.15.4 and WirelessHART to enhance reliability in critical applications.
• The study emphasizes co-optimizing control and communication parameters to improve system stability and efficiency.

Analysis and Design of Wireless Networked Control Systems (WNCS)

The paper "Wireless Network Design for Control Systems: A Survey" provides a detailed examination of Wireless Networked Control Systems (WNCS), which are gaining prominence in various critical control system applications such as automotive electronics, avionics control, building management, and industrial automation. The focus is on the integration of spatially distributed sensors, actuators, and controllers employing wireless communications instead of traditional wired connections. This transition brings significant advantages in terms of cost-effectiveness, flexibility, and enhanced safety. The paper offers an exhaustive review of literature focusing on wireless network design and optimization tailored specifically for WNCS.

Key Components of WNCS

WNCS entail a system design that jointly optimizes the interaction between communication and control systems to enhance network lifetime and control performance. The paper identifies and investigates key interactive variables, including sampling period, message delay, message dropout, and energy consumption. These variables necessitate a carefully orchestrated design for both communication and control systems to ensure optimal operation.

Wireless Network Parameters and Protocols

The paper outlines various protocols that have been adapted for WNCS, including IEEE 802.15.4, WirelessHART, and IEEE 802.15.4e, among others. These protocols provide different methodologies for adapting network parameters to achieve efficient and reliable communication critical for WNCS. It highlights the importance of interactions between Networked Control Systems (NCS) and Wireless Sensor Networks (WSN) and discusses the trades space of designs available for WNCS applications.

Control System Design and Interaction

Designing control systems for WNCS involves accounting for non-idealities introduced by the wireless network, such as message delays and dropouts. The paper examines various control system design approaches considering these factors to ensure system stability and performance. The survey touches on both interactive design approaches – tuning of network parameters in response to control system requirements – and joint design approaches, where communication and control system parameters are co-optimized.

Implications and Future Research

The implications of WNCS research extend heavily into enhancing safety-critical applications by providing more adaptive, reliable, and efficient network designs. The survey draws attention to several promising research directions, including the exploration of more sophisticated models and control algorithms that can efficiently handle the complexities of WNCS. Future developments could include breakthroughs in energy harvesting technologies, enabling even longer network lifespans and supporting more extensive deployments.

Testbeds and Practical Implementation

Furthermore, the paper describes testbeds that simulate and evaluate WNCS performance, which are crucial for testing theoretical models in practical environments. It examines cyber-physical systems that integrate simulations of both control dynamics and network behavior, providing invaluable insights for improving WNCS designs.

Overall, the paper presents a comprehensive framework for understanding the intricate design challenges and optimization strategies necessary for advancing WNCS. It underlines the need for continued research to address the complexities posed by wireless communication in control systems, aiming to foster innovation and deployment in a wide array of industrial applications.