Stability analysis and vibration control of a class of negative imaginary systems

This paper presents stability analysis and vibration control of a class of negative imaginary systems. A flexible manipulator that moves in a horizontal plane is considered and is modelled using the finite element method. The system with two poles at the origin is shown to possess negative imaginary properties. Subsequently, an integral resonant controller (IRC) which is a strictly negative imaginary controller is designed for the position and vibration control of the system. Using the IRC, the closed-loop system is observed to be internally stable and simuation results show that satisfactory hub angle response is achieved. Furthermore, vibration magnitudes at the resonance modes are suppressed by 48 dB

Identification and model predictive position control of Two Wheeled Inverted Pendulum mobile robot

In order to predict and analyse the behaviour of a real system, a simulated model is needed. The more accurate the model the better the response is when dealing with the real plant. This paper presents a model predictive position control of a Two Wheeled Inverted Pendulum robot. The model was developed by system identification using a grey box technique. Simulation results show superior performance of the gains computed using the grey box model as compared to common linearized mathematical model

Sensorless position control of DC motor using model predictive controller

Sensors like rotary encoders are widely used in measuring the speed and position of DC motor in applications. Due to expensiveness, calibration complexities of these type of encoders, sensorless methods for measurements were used alternatively. This paper presents sensorless position control of a wheeled DC motor using system identified model. This approach overcome some conventional sensorless techniques that uses some approximations. The model is developed using black box identification scheme, based on the identified model, a model predictive controller was designed to track a desired horizontal position of the wheel. Practical experiment shows the concept gives a very good estimation of the position and speed and can be used in control application

LMI-based state feedback controller design for vibration control of a negative imaginary system

This paper presents state feedback control via linear matrix inequality (LMI) for vibration control of a flexible link manipulator (FLM) system. FLM is a negative imaginary (NI) system with high amplitude vibration and oscillation. In this work, pole placement controller (PPC) which is NI controller is used to control the FLM vibration, to achieve a precise hub angle positioning with minimum tip deflection. A decay rate is introduced to improve the speed of the system and investigate the effect on the system performance. LMI optimization technique is used to obtain the optimal and best control gains of PPC using Matlab LMI toolbox with different values of the decay rate. Simulation results show that satisfactory hub angle and tip deflection responses are achieved using the proposed controller. Damping is successfully added into the system and reduces the system vibration at the first two vibration modes by 40 dB. Hub angle positioning is achieved with minimum tip deflection by changing the value of decay rate

Adaptive input shaping for sway control of 3D crane using a pole-zero cancellation method

This paper presents an adaptive input shaping based on pole-zero cancellation (APZC) technique to suppress load sway of a crane system. In this method, a reference system is selected and the proposed adaptive shaper is made to force the actual system to adapt to the changes in natural frequency and damping ratio as the cable length increases or decreases. Simulation results are compared with a zero vibration derivative input shaper designed based on average travel length (ATL) to investigate the performance of the proposed shaper. Simulation using three cable length of 0.7 m, 0.5 m and 0.3 m shows that APZC gives better payload sway reduction with smallest maximum swa