Trihastuti Agustinah

Hybrid fuzzy control for swinging up and stabilizing of the pendulum-cart system

This paper presents the design and implementation of a hybrid fuzzy control for the swinging up and stabilizing of the pendulum-cart system. The fuzzy swing-up controller is employed to swing the pendulum up from its pendant position to the stabilization zone in the upright position using as few rules as possible. After the pendulum reaches the zone, the fuzzy stabilizing controller is then switched to stabilize the inverted pendulum at the upright position. The controller is designed based on a robust performance state feedback controller using Linear Matrix Inequalities (LMI) approach for Takagi-Sugeno fuzzy systems. Numerical simulation and real-time experiment are presented to show the effectiveness of the method.

Fuzzy tracking control design using observer-based stabilizing compensator for nonlinear systems

This paper presents fuzzy tracking control design for nonlinear systems. The design methodology is a synthesis of the tracking control theory of linear multivariable control and the Takagi-Sugeno fuzzy model. The observer-based stabilizing compensator type from multivariable tracking control theory is used, because not all states of the nonlinear system are fully available or measured while Takagi-Sugeno (T-S) fuzzy model is used to represent the dynamic of nonlinear system. The concept of parallel distributed compensation is employed to design fuzzy tracker and fuzzy observer from the T-S fuzzy model. The stability analysis of the designed system is derived via the Lyapunov function. Numerical simulation and real-time experiment are provided to illustrate the tracking control design procedure and performance of the proposed methods for practical application.

Reconfigurable Controller Based on Fuzzy Descriptor Observer for Nonlinear Systems with Sensor Faults

In this paper, the FTC system for multiple operating condition nonlinear systems subjected to sensor faults is developed by applying reconfigurable control scheme. The scheme generates any modified control signal using appropriate additive reference signal to the nominal control system. The proposed observer is developed based on descriptor approach in the fuzzy Takagi-Sugeno model configuration in order to accommodate some operating conditions of a nonlinear system. The simulation result shows that the proposed method has capability to compensate more than one sensor fault occurred in a three-tank benchmark system even there is a change in condition operation as well as in reference signal.

Quadcopter path following control design using output feedback with command generator tracker based on LOS

The development of quadcopter technology has much increasing, such as in military and law enforcement agencies, for surveillance, reconnaissance and rescue mission. Also in scientific sides, it is used for mapping the condition of wind speed, detecting radiation sources, maintenance and survey. Quadcopter is a system that still have problem, which is stability, and because of that it can easily get interference from outside. This characteristic leads to the difficulties in automatic controlling the following path and set the heading of Quadcopter. Based on this problem, this paper provides the design of following path control on the horizontal plane by adding Line Of Sight algorithm so it will produce the smallest error possible. The result of the simulation show that the method which used can bring the yaw angle at the expected value algorithm. Quadcopter can do automatically following path with cross track error mean ±0.07 meters.

Design of actuator fault compensation with MRC in 2 DOF manipulator based on PID CTC

All mechanical and electronic systems can run into performance degradation including robot Manipulators. One cause of such performance degradation is due to the occurrence of fault on the actuator. The occurrence of actuator fault on Robot Manipulator 2 DOF (Degree of Freedom) will make tracking of the robot shifted from its reference, cause signal deviation and enlarge overshoot. Estimation and compensation techniques can be a solution to this problem, but these techniques can only be done if the designed system is capable of generating residual signals. This signal is a comparison of the response signal between the actual system and the MRC response signal. This paper explains the design of an AFTC (Active Fault Tolerant Control) algorithm based MRC. When an actuator fault happened, it was estimated and compensated with Model Reference Control (MRC) using Proportional Integral Derivative (PID) based on Computed Torque Control (CTC) law. Simulation result shows that the designed system can compensate actuator fault with small error tracking error about 0.0068 rad and has time response less than 1s. It also reach minimum overshoot through 0.041 rad.

Design of decoupling and nonlinear PD controller for cruise control of a quadrotor

Quadrotor is often used to accomplish various missions related to surveillance, territory mapping, search and rescue, and other purposes. Quadrotor is a nonlinear system with multiple input multiple output and has stability issue due to external disturbance. These characteristics lead to difficulty in cruise control of quadrotor automatically. Decoupling method is used to eliminate the interaction of other control on rotational motion, then the roll, pitch, and yaw angle can be controlled independently. Nonlinear PD controller is obtained from invers model of control signal on a quadrotor and it is used to control the translational motion in x and y axis with nonlinear dynamics because of the influence the rotational angle. Simulation results show that the proposed method can eliminate the control interaction of roll, pitch and yaw angle, hence it works like single input single output system and translational motion on x and y axis can achieve the expected trajectory precisely.

Virtual laboratory design for pendulum-cart control system

This paper describes the design of virtual laboratory using MATLAB for pendulum-cart system. The control system is designed using fuzzy control method. The aims of this virtual laboratory are to help user to do an experiment and learn the dynamic of the pendulum-cart system. The control system designed is applied to the virtual laboratory. The physical form of pendulum-cart system in this virtual laboratory is visualized with 3D graphics simulation and interactive interface. The results of virtual laboratory simulation show that 3D graphics, control system, and the interface can be well integrated.

Reconfigurable fault-tolerant control of linear system with actuator and sensor faults

This paper presents an active fault-tolerant control for linear system in case of actuator and sensor faults where these minor faults lead to degraded performance of the system. Three steps are proposed to achieve fault tolerant control based on simplified analytical redundancy. Firstly, a bank of linear observer is proposed to estimate the actuator and sensor faults by modeling a descriptor LTI system using the SVD technique. Secondly, the estimated faults are used to design a fault decision scheme to detect the faults correctly. Thirdly, a reconfigurable fault-tolerant control scheme is designed by using the estimated faults to compensate the fault effects on controller performance. Simulation on the three tank system is given to illustrate the performance of the proposed method.