| To save the resources in networked control system(NCS) such as network bandwidth, computation and energy, event-triggered mechanism(ETM) has been introduced,and thus event-triggered NCS is formed. Unlike the periodic control that control task is executed at each sampling period, event-triggered control is that control task is only executed when event-triggered condition is satisfied, i.e., event-triggered control can obtain satisfactory control performance while using less system resources. Since eventtriggered NCS has the advantages of both the ETM and NCS, it attracts more and more attentions.However, there also exist some drawbacks in the existing results of the eventtriggered NCS as below:(1) Most works use continuous ETM, which requires dedicated hardware to detect plant information continuously and generate event-triggered interrupts. However, it is often costly or impractical to add dedicated hardware to the original systems.(2) The proposed ETMs can be roughly divided into relative ETM and absolute ETM. However, the transmission rate of relative ETM is high when system runs nearby the origin, whereas the transmission rate of absolute ETM is high when system runs far away from the origin. Namely, neither of the relative ETM and absolute ETM can effectively reduce the transmission rate of sampled data during the whole running time.(3)Most works focus on the architecture that the communication network and ETM exist at the sensor side. However, some other important architectures are seldom considered such as multi-channel communication network and distributed ETM exist at the sensor side, communication network and ETM exist at both the sensor and controller sides, and multi-channel communication network and distributed ETM exist at the sensor and controller sides.(4) Most works study the stability analysis of event-triggered NCS using given controllers. However, it is seldom considered how to design controllers under the effect of the ETM.To overcome the above drawbacks, it is necessary to propose novel ETM, consider more system architectures and study the methods of analysis and synthesis for the resultant event-triggered NCS. Based on the analysis and summary of existing literatures, the main contributions of this thesis are outlined as follows:(1) As for the architecture that nonideal communication network and ETM exist at the sensor side, the discrete ETM based state-feedback NCS with guaranteed H_∞ performance is studied. To reduce the transmission rate of sampled data, a discrete ETM is firstly proposed, which determines whether the event-triggered condition is satisfied at each sampling period. Unlike the periodic sampling mechanism that transmits all sampled data, the discrete ETM only transmits the sampled data when the event-triggered condition is satisfied, thus the transmission rate of sampled data can be effectively reduced.Unlike the continuous ETM requiring dedicated hardware, the discrete ETM is easily realized by software, since it only needs plant information at sampling periods. Besides,since the lower bound of triggering intervals is sampling period, Zeno behavior is absolutely excluded. Then, the closed-loop time-delay system model is established, which characterizes the effects of the discrete ETM and nonideal communication network in a unified framework. Based on Lyapunov stability theory and linear matrix inequality technique, sufficient condition for asymptotic stability with guaranteed H_∞ performance is derived, which depicts the mutually restrictive relationship among the discrete ETM,performance of communication network and system stability. Considering the effect of the discrete ETM, sufficient condition for controller design is also presented. Moreover,conservatism is reduced by the reciprocally convex approach and delay decomposition technique.(2) As for the case that nonideal communication network and ETM exist at the sensor side, and plant state is not measurable, the improved ETM based output-feedback NCS with guaranteed (?)_∞ gain is studied. To overcome the drawbacks that the transmission rate of relative ETM is high when system runs nearby the origin, and the transmission rate of absolute ETM is high when system runs far away from the origin, an improved ETM is firstly proposed by using both the state-dependent and state-independent information, which effectively reduces the transmission rate of sampled data during the whole running time. Then, the closed-loop time-delay system model is established,which characterizes the effects of the improved ETM and nonideal communication network in a unified framework. Sufficient conditions for both ultimately bounded stability and asymptotic stability are derived, and the quantitative relationship between the ultimate bound and the parameters of the improved ETM is also obtained. Besides, the co-design strategy is presented to design simultaneously the output-feedback controller and the improved ETM, which can make the performance of control and communication reach the desired level.(3) As for the architecture that nonideal multi-channel communication network and distributed ETM exist at the sensor side, and wireless sensor network(WSN) is used to detect plant information, the distributed ETM based NCS with guaranteed H_∞ performance is studied. To save sensor energy and network bandwidth, based on topology of the WSN, a distributed ETM is firstly proposed by using the information from both the sensor node and its neighbors. Then, the closed-loop time-delay system model is established, which characterizes the effects of the distributed ETM, topology of the WSN and nonideal multi-channel communication network in a unified framework. Using piecewise-linear characteristics of time-delay function, the quadratic convex approach and the augmented Lyapunov-Krasovski functional that contains cross terms of variables and quadratic terms multiplied by a higher degree scalar function, less-conservative sufficient condition for asymptotic stability with guaranteed H_∞ performance is derived,which depicts the mutually restrictive relationship among the distributed ETM, topology of the WSN, performance of multi-channel communication network and system stability. Besides, less-conservative sufficient condition for designing simultaneously the controller and distributed ETM is also presented.(4) As for the architecture that nonideal communication network and ETM exist at both the sensor and controller sides, the dual-side ETMs based NCS with guaranteed H_∞ performance is studied. To reduce the transmission rate of sampled data at the sensor and controller sides, dual-side ETMs are proposed by using the plant and controller information, respectively. Then, the closed-loop time-delay system model is established, which characterizes the effects of dual-side communication networks and dual-side ETMs in a unified framework. Besides, using data processing units with buffers at both sides,time-varying transmission delay is transformed into constant delay, and sufficient condition for asymptotic stability with guaranteed H_∞ performance is derived, which depicts the mutually restrictive relationship among the dual-side ETMs, performance of dualside communication networks and system stability. Moreover, sufficient condition for designing simultaneously the controller and dual-side ETMs is also presented.(5) As for the architecture that nonideal multi-channel communication network and distributed ETM exist at the sensor and controller sides, the dual-side distributed ETMs based NCS with guaranteed (?)_∞ gain is studied. To effectively reduce the transmission rate of sampled data in each channel at both sides during the whole running time, the dual-side distributed ETMs are proposed by selectively using plant, controller and state-independent information. Then, the closed-loop time-delay system model is established, which characterizes the effects of dual-side distributed ETMs and dual-side multi-channel communication networks in a unified framework. Sufficient conditions for both ultimately bounded stability and asymptotic stability are derived, and the quantitative relationship between the ultimate bound and parameters of dual-side distributed ETMs is also obtained. Considering the effect of dual-side distributed ETMs, sufficient condition for controller design is also presented.
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