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This diploma thesis describes the design and implementation of an industrial communicator for synchronization and control of electrical drive controllers with the interface of RS232 or CANopen. Hardware of communicator uses the EMX development system by GHI Electronics. Communicator software is implemented in C# by the .NET Micro Framework. Communicator allows user to adjust and control up to four electric motor drives. After a successful connection with each unit, communicator can control its position, which specify the number of revolutions to the nearest thousandth of a turn. Communicator also periodically finds out and displays the current position of the connected units. User operates the communicator with GUI, application instructions are entered via the touch screen or buttons.

Background: This study, the first of its kind, originated with the need for a brace (an ankle foot orthosis), to constrain ankle plantarflexion and dorsiflexion within a motion threshold of <5°. A conventional thermoplastic, solid brace failed during a quasi-static loading study, informing the investigation and development of an experimental carbon composite brace, maximizing stiffness and proximity of shank and foot cylindrical shells to provide the required degree of control. Methods: Two experiments were conducted: a quasi-static loading study, using cadaveric limbs (n = 2), and a gait study with healthy subjects (n = 14). Conditions tested were STOP, FREE, and CONTROL. Data for all studies were collected using six motion-capture cameras (Vicon, Oxford, UK; 120 Hz) tracking bone-anchored markers (cadaveric limbs) and skin-anchored markers (subjects). In the quasi-static loading study, loading conditions were congruent with the gait study. Study 1 involved a quasi-static loading analysis using cadaveric limbs, compared motion data from a conventional thermoplastic solid brace and the experimental brace. Study 2 involved quantifying ankle plantarflexion and dorsiflexion in subjects during treadmill walking, in brace STOP, FREE, and CONTROL conditions. Findings: The experimental brace in STOP condition consistently constrained ankle plantarflexion and dorsiflexion below the motion threshold of <5°, across all studies. Interpretation: Collectively, these findings demonstrate (1) that a conventional thermoplastic, solid brace was ineffective for clinical applications that required significant motion control, and (2) that ankle motion control is most effective when considered as a relationship between the brace, the ankle-foot complex, and the external forces that affect them both.

Moore’s law states that the number of transistors in an Integrated Circuit (IC) doubles every two years. Ever-increasing performance in mask writing machinery is therefore required being the first step in the manufacturing process. Many factors affect the quality of the end product, with the motion control system playing an important role. This thesis analyzes the performance of the motion controller for the positioning system in a mask writer application. The target motion in the X-axis in the mask writer is by design highly repetitive and predictable. As of today a feedforward-feedback controller is used, tuned for low deviation during writing. In this thesis it is found that the motion control can be improved by exploiting the repetitive nature of the motion task. Two iterative methods are explored, Iterative Feedback Tuning (IFT) and Iterative Learning Control (ILC). IFT is implemented as a parameter optimizing method for the existing Proportional-Integral-Derivative (PID) controller. Given suboptimal initial parameters the algorithm converges to a global minimum using a cost function to minimize total deviation and constraints on the maximum deviation. With the optimized parameter settings an improvement of a 31 % decrease in total deviation is seen compared to the default setting. ILC is implemented as a replacement to the current controller in an exposure motion. With the use of saved data from previous iterations the control signal is updated and refined to better suit the target motion. ILC is a promising method within high precision motion control by virtue of not needing a model of the system and its ability to suppress reoccurring disturbances. The algorithm achieves an improvement of a 94% decrease in total deviation during writing compared to the current controller. However, with this implementation long term stability is not guaranteed. A stable implementation of the algorithm tested on a test rig achieves an improvement of a 79.8% decrease in deviation during writing compared to the current feedforward-feedback controller. Additionally, correlations between parameter values of the current feedback controller and servo characteristics are analyzed to aid in the manual tuning process. Tuning the PID controller for fast rise time decreases the total deviation during writing. The derivative gain in the controller should be high to decrease the overshoot caused by the aggressive controller. This will induce some oscillations into the system, however not at the cost of performance as a result of the smooth motion during writing.

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This thesis presents model-based adaptive motion control algorithms for under-actuated aerial robotic manipulators combining a conventional multi-rotor Unmanned Aerial Vehicle (UAV) and a multi-link serial robotic arm. The resulting control problem is quite challenging due to the complexity of the combined system dynamics, under-actuation, and possible kinematic redundancy. The under-actuation imposes second-order nonholonomic constraints on the system motion and prevents independent control of all system degrees of freedom (DOFs). Desired reference trajectories can only be provided for a selected group of independent DOFs, whereas the references for the remaining DOFs must be determined such that they are consistent with the motion constraints. This restriction prevents the application of common model-based control methods to the problem of this thesis. Using insights from the system under-actuated dynamics, four motion control strategies are proposed which allow for semi-autonomous and fully-autonomous operation. The control algorithm is fully developed and presented for two of these strategies; its development for the other two configurations follows similar steps and hence is omitted from the thesis. The proposed controllers incorporate the combined dynamics of the UAV base and the serial arm, and properly account for the two degrees of under-actuation in the plane of the propellers. The algorithms develop and employ the second-order nonholonomic constraints to numerically determine motion references for the dependent DOFs which are consistent with the motion constraints. This is a unique feature of the motion control algorithms in this thesis which sets them apart from all other prior work in the literature of UAVmanipulators. The control developments follow the so-called method of virtual decomposition, which by employing a Newtonian formulation of the UAV-Manipulator dynamics, sidesteps the complexities associated with the derivation and parametrization of a lumped Lagrangian dynamics model. The algorithms are guaranteed to produce feasible control commands as the constraints associated with the under-actuation are explicitly considered in the control calculations. A method is proposed to handle possible kinematic redundancy in the presence of second-order motion constraints. The control design is also extended to include the propeller dynamics, for cases that such dynamics may significantly impact the system response. A Lyapunov analysis demonstrates the stability of the overall system and the convergence of the motion tracking errors. Experimental results with an octo-copter integrated with a 3 DOF robotic manipulator show the effectiveness of the proposed control strategies. / Thesis / Doctor of Philosophy (PhD)

在3D遊戲中，讓虛擬角色能夠在場景中自主的和使用者進行即時互動，一直是一個非常有挑戰性的問題。過去在此方面的相關研究雖然為數不少，但大多數的研究不是用效能來換取角色動作的規劃品質，就是屈就於效能而決定犧牲品質，能妥善的在兩者之間取得平衡的系統並不常見。本論文所提出的系統，便是一個能在兩者之間取得不錯平衡的角色動作規劃器。我們的規劃器會根據使用者的操作命令來預測角色未來可行的行動空間，並搭配時間預算的概念，將這些預測結果儲存在一種稱為可行動作樹的資料結構，從這些預測結果中搜尋出最符合使用者操作要求的角色動作。我們利用這個規劃器實作了兩種不同的應用，並測試了它們的效能。我們相信這個運動模組能實用在一般如遊戲的即時動畫環境中，提昇動畫角色的互動性與動畫品質。 / Allowing a virtual character to interact with the user autonomously in a 3D game has been a challenging problem for long. There has been much research in this direction but most of them have to trade interactivity of control with the quality of the generated motions or the other way. It is rare to see a system that can find a good balance between these two factors. In this thesis, we propose an interactive system consisting of a motion planner aiming to find a good balance between these two factors. Our planner attempts to predict the feasible motion space in the near future according to user commands. We use the concept of time-budgeted computing to maintain a data structure called Feasible Motion Tree representing the feasible motion space. This tree is maintained in an incremental fashion and is used to select the most appropriate motion clip when the current motion clip comes to the end. We have used this motion planning module to implement two different applications and verify its efficacy and efficiency. We believe that this motion planning module can be used in a real-time virtual environment, such as a game, for the improvement of the interactivity and the quality of motion control.