This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination. IEEE TRANSACTIONS ON CYBERNETICS 1 Adaptively Adjusted Event-Triggering Mechanism on Fault Detection for Networked Control Systems Yu-Long Wang, Member, IEEE, Cheng-Chew Lim, Senior Member, IEEE, and Peng Shi, Fellow, IEEE Abstract—This paper studies the problem of adaptively adjusted event-triggering mechanism-based fault detection for a class of discrete-time networked control system (NCS) with appli- cations to aircraft dynamics. By taking into account the fault occurrence detection progress and the fault occurrence proba- bility, and introducing an adaptively adjusted event-triggering parameter, a novel event-triggering mechanism is proposed to achieve the efficient utilization of the communication network bandwidth. Both the sensor-to-control station and the con- trol station-to-actuator network-induced delays are taken into account. The event-triggered sensor and the event-triggered con- trol station are utilized simultaneously to establish new network- based closed-loop models for the NCS subject to faults. Based on the established models, the event-triggered simultaneous design of fault detection filter (FDF) and controller is presented. A new algorithm for handling the adaptively adjusted event-triggering parameter is proposed. Performance analysis verifies the effec- tiveness of the adaptively adjusted event-triggering mechanism, and the simultaneous design of FDF and controller. Index Terms—Adaptively adjusted event-triggering, fault detection filter (FDF), networked control system (NCS). I. I NTRODUCTION N ETWORKED control systems (NCSs) are control sys- tems wherein the control loops are closed through a shared band-limited digital communication network. The defining feature of NCSs is that control and feedback signals are transmitted among the systems’ components in the form of data packets through a communication network. NCSs have been the subject of intensive research in areas from robust Manuscript received March 28, 2016; revised September 7, 2016 and November 6, 2016; accepted November 19, 2016. This work was supported in part by the Australian Research Council under Grant DP140102180, in part by the National Science Foundation of China under Grant 61374063, Grant 61403170, and Grant U1509217, in part by the “333 Project” Research Foundation of Jiangsu Province, China, under Grant BRA2015358, in part by the Natural Science Foundation of Jiangsu Province, China, under Grant BK20161361, and in part by the “Six Talent Peaks Project” of Jiangsu Province, China, under Grant DZXX-025. This paper was recommended by Associate Editor G.-P. Liu. (Corresponding author: Peng Shi.) Y.-L. Wang is with the School of Electronics and Information, Jiangsu University of Science and Technology, Zhenjiang 212003, China (e-mail: feixiangwyl@163.com). C.-C. Lim and P. Shi are with the School of Electrical and Electronic Engineering, University of Adelaide, Adelaide, SA 5005, Australia (e-mail: cheng.lim@adelaide.edu.au; peng.shi@adelaide.edu.au). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TCYB.2016.2631903 H 2 /H ∞ control [1], sequence-based control [2], fuzzy con- trol [3], [4], quantized control [5], asynchronous sampling [6], time-varying sampling [7], [8], multirate control [9], [10], to observer-based control [11], and many more. Industrial control systems are generally subject to faults. The work in [12] investigated fault-tolerant flight control design for aircraft systems. Fault detection has been an active research topic, and great efforts have been made to inves- tigate fault detection and fault compensation for traditional control systems (see [13], [14] and the references therein). Some nice results on fault detection for NCSs have also been achieved [15]–[22]. Note that network-induced delays are ignored in [15]–[18]; plant state delays instead of network- induced delays are taken into account in [19]; network-induced delays are not included in the established model in [20]; and the sensor-to-fault detection filter network-induced delays are considered in [21] and [22]. Moreover, no control input is con- sidered in [21], while network-induced transmission delays of control inputs are ignored in [22]. In this paper, we introduce a control station consisting of the fault detection filter (FDF) and the controller to study the problem of fault detection. However, inserting the sensor-to-control station and the con- trol station-to-actuator communication networks will induce network transmission delays inevitably. For NCSs subject to faults, since both the plant and the FDF are described as dynamic systems, taking into account the sensor-to-control sta- tion and the control station-to-actuator network-induced delays will introduce considerable difficulty for network-based mod- eling and the simultaneous design of FDF and controller. How to address these issues is practically valuable and still unre- solved in [13]–[22]. This gives the first motivation of this paper. In the aforementioned works, the plant states or measure- ment outputs are sampled at specific sampling periods and then transmitted to the controller and/or FDF periodically through a communication network. Generally speaking, transmitting all the sampled data packets can lead to a good system per- formance. However, this may not always be the truth. On the one hand, if the communication network cannot pro- vide enough network bandwidth, releasing all the sampled data packets into the communication network may cause net- work congestion. On the other hand, if the fluctuations of the sampled states or measurement outputs are not worth acting on, releasing all the sampled data packets into the com- munication network is a waste of scarce network resources. 2168-2267 c  2016 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications_standards/publications/rights/index.html for more information.