Time-varying sliding mode controller for heat exchanger with dragonfly algorithm

This article proposes the design of a sliding mode controller with a time-varying sliding surface for the plate heat exchanger. A time-varying sliding mode controller (TVSMC) combines the benefit of the control system’s robustness and convergence rate. Using Lyapunov stability theory, the stability of the designed controller is proved. In addition, the controller parameters of the designed controller are specified optimally via the dragonfly algorithm (DA). The input constraint’s effect is considered in the controller design process by applying the concept of the auxiliary system. The bounded disturbances are applied to investigate the robustness of the proposed techniques. Moreover, the quasi-sliding mode controller (QSMC) is developed as a benchmark to evaluate the convergence behavior of the proposed TVSMC technique. The simulation results demonstrate the proposed TVSMC with the optimal parameters provided by the DA algorithm (TVSMC+DA) can regulate the temperature to the desired level under bounded disturbances. When compared to the QSMC method, the TVSMC+DA performs significantly faster convergence speed and greater reduction in chattering occurrence. The results clearly indicate that the proposed controller can enhance convergence properties while being robust to disturbances

Application of the Terminal Synergetic Control for Biological Control of Sugarcane Borer

Sugarcane is an important agricultural commodity in economics that has been harmed by the invasion of sugarcane borer. Establishing a biological pest control strategy for sugarcane using their natural enemies can both protect agricultural products from pest invasion and the environment from chemical toxicity. In this regard, feedback control emerges as a practical and feasible approach to effectively implement the biological control strategy for managing the sugarcane borer. In this work, the terminal synergetic controller (TSC) was designed to develop a control strategy containing multiple inputs. The controller design was conducted based on the pest-parasitoid model. In the design procedure, the auxiliary system was employed to compensate for the input saturation effects. The control stability was conducted through the Lyapunov stability theorem. To confirm the capability and performance of the proposed strategy, the simulation results demonstrate that it can effectively regulate pest population densities at the desired level, comparable to both the conventional sliding mode control (SMC) and verticum-type control (VC) strategies. However, what sets it apart is that the terminal synergetic controller provides the preferable characteristics for controlling the sugarcane borer population which are the finite-time convergence of the control system, and the absence of chattering phenomena in the control inputs

An In-Pipe Inspection Robot with Permanent Magnets and Omnidirectional Wheels: Design and Implementation

This paper aims to present the design and prototype of an inspection robot that can perform both horizontal and vertical locomotion in ferromagnetic pipelines. The proposed robot applies to a range from 5-inch (127 mm) diameter pipes to flat plates. The train-like robot is mainly composed of three sealed modules with omnidirectional driving wheels for longitudinal and transverse movements. Permanent magnets were designed to provide sufficient magnetic adhesion between the robot and the ferromagnetic surface of the pipes. The internal condition of the pipe can be monitored visually through cameras and sensors. Specific experimental conditions have been carried out to validate the robot’s capabilities, including maximum speed, payload capacity, and vertical climbing distance. The experimental results also show that the robot is capable of passing through a straight pipe and elbow fitting in both upward and downward directions

An In-Pipe Inspection Robot with Permanent Magnets and Omnidirectional Wheels: Design and Implementation

This paper aims to present the design and prototype of an inspection robot that can perform both horizontal and vertical locomotion in ferromagnetic pipelines. The proposed robot applies to a range from 5-inch (127 mm) diameter pipes to flat plates. The train-like robot is mainly composed of three sealed modules with omnidirectional driving wheels for longitudinal and transverse movements. Permanent magnets were designed to provide sufficient magnetic adhesion between the robot and the ferromagnetic surface of the pipes. The internal condition of the pipe can be monitored visually through cameras and sensors. Specific experimental conditions have been carried out to validate the robot’s capabilities, including maximum speed, payload capacity, and vertical climbing distance. The experimental results also show that the robot is capable of passing through a straight pipe and elbow fitting in both upward and downward directions