The objective of this thesis is to solve the trajectory tracking control problems of the mobile manipulators in two stages. In the first stage, a desired velocity input function for a steering system is designed by using Lyapunov stability theorem so that the posture of the mobile manipulator can track the reference trajectory. Further analysis shows that the vehicle of the mobile manipulator will achieve better result of trajectory tracking than the existent methods if the reference trajectory of the vehicle is not assigned to be static condition. In the second stage, the torque controller of the dynamic equations of the mobile manipulator with perturbations and input uncertainty is designed by adaptive variable structure control (AVSC) methodology, so that the actual velocity can track the desired velocity input function designed in the first stage. In addition, this controller with an adaptive mechanism embedded is capable of suppressing the perturbations with unknown upper bound except that from the input channel, and achieve asymptotical stability under certain mild conditions. Finally, an example of a two-link wheeled mobile manipulator is presented to demonstrate the feasibility of the proposed control schemes.

In conventional tracking algorithms the targets are usually considered as point source objects. However, in realistic scenarios the point source assumption is often not suitable and estimating the states of an object extension characterized by a collectively moving ballistic object group (cluster) becomes a very critical and relevant problem which has applications in the defense area. Recently, a Bayesian approach to extended object tracking using random matrices has been proposed. Within this approach, ellipsoidal object extensions are modeled by random matrices and treated as additional state variables to be estimated. In this work we propose to use a slightly modified version of this new approach that simultaneously estimates the ellipsoidal shape and the kinematics of a group of ballistic targets. Target group that is tracked consists of subsequent projectiles. We use JPDAF framework together with the new approach to emphasize the pros and cons of both approaches. The methods are demonstrated and evaluated in detail by making various simulations.

Abstract A simple design methodology of robust adaptive sliding m de utput tracking controllers for a class of MIMO nonlinear mismatched perturbed systems is presented in this thesis.First,the derivatives of tracking error

Based on Lyapunov theorem, two different types of control schemes for solving robust tracking problems are presented in this thesis. The first one is model reference adaptive sliding mode control, which is designed for a class of SISO LTI systems with relative degree one possessing additive and multiplicative unstructured uncertainties in the input and output channels. By introducing a perturbation estimation process embedded in the proposed control scheme, the chattering phenomenon can be reduced effectively since only the perturbation estimation error needs to be overcomed. The second one is optimal model reference adaptive control, which is designed for a class of multi-input systems with input non-linearity. These systems are subject to model uncertainties and time-varying delay.

Optical flow, caused by relative motion of the object and the viewer, is the distribution of apparent velocities of brightness pattern in an image. The advantage of the optical-flow-based visual servo method is that feature of the object does not need to be defined or known in advance. This research plans to build an image servo technique to deal with the problem of 3D relative motion of the viewer and the environment. The images are treated as input and output signals of the control system and are fed back to extract the relative velocity information between contiguous image patterns. Then the video camera will automatically follow the motion to maintain the target image unchanged.

As the electronic products are gotten smaller and the quantity of output is to be requested, the trend of the needs for speed and accuracy is more precise. Therefore, upgrading the speed and the accuracy of contour error on tracking control has become an important point. This research is focus on the improvement of tracking error and contour error. In tracking error, we propose that the compensation of friction disturbance is by building friction model. And then adaptive robust controller is used to eliminate other disturbance. Finally, velocity feedforward controller is used to improve system dynamic response and to remove the effect of time delay. The combination of such controllers can improve tracking error directly and contour error indirectly. In contour error, we use cross-coupled controller to coordinate the motors and to reform contour error. On the association of such controllers, we propose the design method of cross-coupled controller, to replace the traditional way of try-and-error, and improving contour error again. Finally, the above improving strategies are verified by the simulation and experimental results.

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Based on the Lyapunov stability theorem, a model reference adaptive variable structure control (MRAVSC) scheme with perturbation estimation is presented in this thesis for solving robust tracking problems. The plant considered belongs to a class of MIMO linear time invariant systems with arbitrary relative degree possessing additive and multiplicative unstructured uncertainties in the input and output channels. By introducing a perturbation estimation process embedded in the proposed control scheme, both the perturbations and differentials of tracking errors can be estimated. In addition, the proposed control scheme also contains an adaptive mechanism in order to automatically adapt the unknown upper bound of perturbation estimation error, and guarantee the property of uniformly ultimate boundedness for the closed-loop controlled system. Finally, two numerical examples are presented to demonstrate the feasibility of the proposed control scheme.

In this thesis the synchronization of two different chaotic systems with matched and mismatched perturbations are developed by utilizing adaptive backstepping control technique. The adaptive mechanisms embeded in the proposed control scheme is used to adapt the unknown upper bounds of the perturbations. The resultant robust backstepping tracking controller with adaptive mechanisms can indeed drive the trajectories of the slave system to track those of the master system. Two numerical examples and simulations are given to illustrate the correctness of theoretical analyses.

This thesis consists of two parts. The first part includes design and implementation of an RF tuner module for DVB-T receiver applications. The RF tuner module adopts single-conversion architecture and has a variable gain range of more than 60 dB. After improving the tracking filter characteristics, the module can achieve an image rejection of 60 dB. The second part is focused on DVB-T RF specification test for the implemented RF tuner module. This test uses the instruments accepted by DVB association to perform the standard measurement procedure. The measured sensitivity of the module is about -86 dBm, which has good ability to receive DVB-T signal in practical environment.