This report describes the development of a low cost open source semiautonomous robotic car and a way to communicate with it. It is a continuation of prior research done by other students at FAU and published in recent ASEE conferences. The objective of this project was the development of a new robotic platform with improved precision over the original, while still keeping the cost down. It was developed with the aim to allow a hands-on approach to the teaching of mathematics topics that are taught in the K-12 syllabus. Improved robustness and reliability of the robotic platform for visually solving math problems was achieved using a combination of PID loops to keep track of distance and rotation. The precision was increased by changing the position of the encoders to the shafts of each motor. A mobile application was developed to allow the student to draw the geometric shapes on the screen before the car draws them. The mobile application consists of two parts, the canvas that the user uses to draw the figure and the configure section that lets the user change the parameters of the controller. Results show that the robot can draw standard geometric and complex geometric shapes. It has high precision and sufficient accuracy, the accuracy can be improved with some mechanical adjustments. During testing a Pythagorean triangle was drawn to show visually the key mathematics concept. The eventual goal of this project will be a K-12 class room study to obtain the feedback of the teachers and students on the feasibility of using a robotic car to teach math. Subsequent to that necessary changes will be made to manufacture a unit that is easy to assemble by the teacher. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

As humans explore greater depths of Earth’s oceans, there is a growing need for the installation of subsea structures. 71% of the earth’s surface is ocean but there are limitations inherent in current detection instruments for marine applications leading to the need for the development of underwater platforms that allow research of deeper subsea areas. Several underwater platforms including Autonomous Underwater Vehicles (AUVs), Remote Operated Vehicles (ROVs), and wave gliders enable more efficient deployment of marine structures. Deployable structures are able to be compacted and transported via AUV to their destination then morph into their final form upon arrival. They are a lightweight, compact solution. The wrapped package includes the deployable structure, underwater pump, and other necessary instruments, and the entire package is able to meet the payload capability requirements. Upon inflation, these structures can morph into final shapes that are a hundred times larger than their original volume, which extends the detection range and also provides long-term observation capabilities. This dissertation reviews underwater platforms, underwater acoustics, imaging sensors, and inflatable structure applications then proposes potential applications for the inflatable structures. Based on the proposed applications, a conceptual design of an underwater tubular structure is developed and initial prototypes are built for the study of the mechanics of inflatable tubes. Numerical approaches for the inflation process and bending loading are developed to predict the inflatable tubular behavior during the structure’s morphing process and under different loading conditions. The material properties are defined based on tensile tests. The numerical results are compared with and verified by experimental data. The methods used in this research provide a solution for underwater inflatable structure design and analysis. Several ocean morphing structures are proposed based on the inflatable tube analysis. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

A crescente complexidade do controle dos processos industriais vem exigindo sistemas de controle cada vez mais precisos, confiáveis e versáteis. No sentido de atender a estas exigências, algoritmos diversos de controle e estimação, tais como: técnicas de controle adaptativas, preditivas, estimação paramétrica, filtros de Kalman, observação de estados, etc. têm sido desenvolvidas, simuladas e implementadas com relativa facilidade nos modernos sistemas digitais. Este trabalho propõe uma estratégia de controle em redes Fieldbus usando controle adaptativo por modelo de referência através de variáveis de estado, para resolver sistemas complexos. O algoritmo de controle proposto é composto por um observador de estados trabalhando em conjunto com um esquema de controle adaptativo por modelo de referência. As malhas de controle no Fieldbus consistem em um conjunto de blocos funcionais padrões existentes, conectados aos novos blocos funcionais propostos e desenvolvidos de acordo com as especificações da norma Fieldbus Foundation. Este algoritmo de controle realiza os cálculos de maneira distribuída entre os dispositivos da rede Fieldbus, implicando em várias vantagens, tais como: a) perda do supervisório não implica na perda do algoritmo de controle, b) menor tráfego de dados na rede, c) algoritmo de controle que não depende do tempo de processamento do computador. Os resultados dos testes obtidos são apresentados e demonstraram um alto grau de precisão, destacando-se a estabilidade e aplicabilidade do algoritmo proposto. / The rising complexity of the industrial control processes has been claiming more and more accurate, reliable and versatile control systems. Attempting to satisfy this demand, several control and estimation systems algorithms, such as adaptive and predictive techniques, parametric estimation, Kalman filtering, state observation, have been designed, simulated and implemented with relative easiness in the modern digital systems. This work proposes a new control strategy in Fieldbus networks, using adaptive control techniques through state variables, to solve complex systems. The proposed control algorithm is based on an states observer concurrently working with a reference model adaptive control scheme. The modified Fieldbus network consists of a set of standard function blocks, connected to the proposed new function blocks. These new function blocks comply with the specifications of the Fieldbus Foundation norm. This control algorithm accomplishes its calculation in a distributed way among the fieldbus devices. This operating feature results in some advantages, such as: any failure in the supervisory system does not imply in the loss of the control algorithm, b) a lower data transmission in the network, c) control algorithm that does not depend on the processing time of the computer. The obtained results corroborate with the expected advantages of the proposed algorithm, in terms of high degree of accuracy, stability and applicability.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-07-18T19:31:22Z No. of bitstreams: 1 MadsonMachado.pdf: 3046442 bytes, checksum: 71cc6800f83fdbf38b97607067653f63 (MD5) / Made available in DSpace on 2017-07-18T19:31:22Z (GMT). No. of bitstreams: 1 MadsonMachado.pdf: 3046442 bytes, checksum: 71cc6800f83fdbf38b97607067653f63 (MD5) Previous issue date: 2017-05-26 / The need to increase industrial productivity coupled with quality and low cost requirements has generated a demand for the development of high performance controllers. Motivated by this demand, we presented in this work models, algorithms and a methodology for the online project of high-performance control systems. The models have characteristics of adaptability through adaptive control system architectures. The models developed were based on artificial neural networks of radial basis function type, for the online project of model reference adaptive control systems associated with the of sliding modes control. The algorithms and the embedded system developed for the online project were evaluated for tracking mobile targets, in this case, the solar radiation. The control system has the objective of keeping the surface of the photovoltaic module perpendicular to the solar radiation, in this way the energy generated by the module will be as high as possible. The process consists of a photovoltaic panel coupled in a structure that rotates around an axis parallel to the earth’s surface, positioning the panel in order to capture the highest solar radiation as function of its displacement throughout the day. / A necessidade de aumentar a produtividade industrial, associada com os requisitos de qualidade e baixo custo, gerou uma demanda para o desenvolvimento de controladores de alto desempenho. Motivado por esta demanda, apresentou-se neste trabalho modelos, algoritmos e uma metodologia para o projeto online de sistemas de controle de alto desempenho. Os modelos apresentam características de adaptabilidade por meio de arquiteturas de sistemas de controle adaptativo. O desenvolvimento de modelos, baseia-se em redes neurais artificiais (RNA), do tipo função de base radial (RBF, radial basis function), para o projeto online de sistemas de controle adaptativo do tipo modelo de referência associado com o controle de modos deslizantes (SMC, sliding mode control). Os algoritmos e o sistema embarcado desenvolvidos para o projeto online são avaliados para o rastreamento de alvos móveis, neste caso, o rastreamento da radiação solar. O sistema de controle tem o objetivo de manter a superfície do módulo fotovoltaico perpendicular à radiação solar, pois dessa forma a energia gerada pelo módulo será a maior possível. O processo consiste de um painel fotovoltaico acoplado em uma estrutura que gira em torno de um eixo paralelo à superfície da terra, posicionando o painel de forma a capturar a maior radiação solar em função de seu deslocamento ao longo do dia.

Durante a operação de um controlador MPC, a planta pode ir para outro ponto de operação principalmente pela decisão operacional ou pela presença de perturbações medidas/não-medidas. Assim, o modelo do controlador deve ser adaptado para a nova condição de operação favorecendo o controle sob as novas condições. Desta forma, as condições ótimas de controle podem ser alcançadas com a maior quantidade de modelos identificados e com um controlador adaptativo que seja capaz de selecionar o melhor modelo. Neste trabalho é apresentada uma metodologia de controle adaptativo com identificação on-line do melhor modelo o qual pertence a um conjunto previamente levantado. A metodologia proposta considera um controlador em duas camadas e a excitação do processo através de um sinal GBN na camada de otimização com o controlador em malha fechada. Está sendo considerada a validação deste controlador adaptativo através da comparação dos resultados com duas diferentes técnicas Controlador MMPC e Identificação ARX, para a comprovação dos bons resultados desta metodologia. / During the operation of a MPC, the plant can change the operation point mainly due to management decision or due to the presence of measured or unmeasured disturbances. Thus, the model of the controller must be adapted to improve the control in the new operation conditions. In such a way, a better control policy can be achieved if a large number of models are identified at the possible operation points and it is available an adaptive controller that is capable of selecting the best model. In this work is presented a methodology of adaptive control with on-line identification of the most adequate model which belongs to a set of models previously obtained. The proposed methodology considers a two-layer controller and process excitation by a GBN signal in the LP optimization layer with the controller in closed loop mode. It is also presented the adaptive controller validation by comparing the proposed approach with two different techniques - MMPC and ARX Identification, to confirm the good results with this new methodology to the adaptive controller.

The goal of this thesis is to use the Cal Poly Spacecraft Attitude Dynamics Simulator to provide proof of concept of two adaptive control theories developed by former Cal Poly students: Nonlinear Direct Model Reference Adaptive Control and Adaptive Output Feedback Control. The Spacecraft Attitude Dynamics Simulator is a student-built air bearing spacecraft simulator controlled by four reaction wheels in a pyramidal arrangement. Tests were performed to determine the effectiveness of the two adaptive control theories under nominal operating conditions, a “plug-and-play” spacecraft scenario, and under simulated actuator damage. Proof of concept of the adaptive control theories applied to attitude control of a spacecraft is provided. The adaptive control theories are shown to attain similar or improved performance over a Full State Feedback controller. However, the measurement capabilities of the simulator need to be improved before strong comparisons between the adaptive controllers and Full State Feedback can be achieved.

Fixed-wing unmanned aerial vehicles (UAVs) with the ability to hover combine the speed and endurance of traditional fixed-wing fight with the stable hovering and vertical takeoff and landing (VTOL) capabilities of helicopters and quadrotors. This combination of abilities can provide strategic advantages for UAV operators, especially when operating in urban environments where the airspace may be crowded with obstacles. Traditionally, fixed-wing UAVs with hovering capabilities had to be custom designed for specific payloads and missions, often requiring custom autopilots and unconventional airframe configurations. With recent government spending cuts, UAV operators like the military and law enforcement agencies have been urging UAV developers to make their aircraft cheaper, more versatile, and easier to repair. This thesis discusses the use of the commercially available ArduPilot open source autopilot, to autonomously transition a fixed-wing UAV to and from hover flight. Software modifications were made to the ArduPilot firmware to add hover flight modes using both Proportional, Integral, Derivative (PID) Control and Model Reference Adaptive Control (MRAC) with the goal of making the controllers robust enough so that anyone in the ArduPilot community could use their own ArduPilot board and their own fixed-wing airframe (as long as it has enough power to maintain stable hover) to achieve autonomous hover after some simple gain tuning. Three new hover flight modes were developed and tested first in simulation and then in flight using an E-Flight Carbon Z Yak 54 RC aircraft model, which was equipped with an ArduPilot 2.5 autopilot board. Results from both the simulations and flight test experiments where the airplane transitions both to and from autonomous hover flight are presented.

Prohibitive cost and large size of conventional angular rate sensors have limited their use to large scale aeronautical applications. However, the emergence of MEMS technology in the last two decades has enabled angular rate sensors to be fabricated that are orders of magnitude smaller in size and in cost. The reduction in size and cost has subsequently encouraged new applications to emerge, but the accuracy and resolution of MEMS angular rate sensors will have to be greatly improved before they can be successfully utilised for such high end applications as inertial navigation. MEMS angular rate sensors consist of a vibratory structure with two main resonant modes and high Q factors. By means of an external excitation, the device is driven into a constant amplitude sinusoidal vibration in the first mode, normally at resonance. When the device is subject to an angular rate input, Coriolis acceleration causes a transfer of energy between the two modes and results in a sinusoidal motion in the second mode, whose amplitude is a measure of the input angular rate. Ideally the only coupling between the two modes is the Coriolis acceleration, however fabrication imperfections always result in some cross stiffness and cross damping effects between the two modes. Much of the previous research work has focussed on improving the physical structure through advanced fabrication techniques and structural design; however attention has been directed in recent years to the use of control strategies to compensate for these structural imperfections. The performance of the MEMS angular rate sensors is also hindered by the effects of time varying parameter values as well as noise sources such as thermal-mechanical noise and sensing circuitry noise. In this thesis, MEMS angular rate sensing literature is first reviewed to show the evolu- tion of MEMS angular rate sensing from the basic principles of open-loop operation to the use of complex control strategies designed to compensate for any fabrication imperfections and time-varying effects. Building on existing knowledge, a novel adaptively controlled MEMS triaxial angular rate sensor that uses a single vibrating mass is then presented. Ability to sense all three components of the angular rate vector with a single vibrating mass has advantages such as less energy usage, smaller wafer footprint, avoidance of any mechanical interference between multiple resonating masses and removal of the need for precise alignment of three separate devices. The adaptive controller makes real-time estimates of the triaxial angular rates as well as the device cross stiffness and cross damping terms. These estimates are then used to com- pensate for their effects on the vibrating mass, resulting in the mass being controlled to follow a predefined reference model trajectory. The estimates are updated using the error between the reference model trajectory and the mass's real trajectory. The reference model trajectory is designed to provide excitation to the system that is sufficiently rich to enable all parameter estimates to converge to their true values. Avenues for controller simplification and optimisation are investigated through system simulations. The triaxial controller is analysed for stability, averaged convergence rate and resolution. The convergence rate analysis is further utilised to determine the ideal adaptation gains for the system that minimises the unwanted oscillatory behaviour of the parameter estimates. A physical structure for the triaxial device along with the sensing and actuation means is synthesised. The device is realisable using MEMS fabrication techniques due to its planar nature and the use of conventional MEMS sensing and actuation elements. Independent actuation and sensing is achieved using a novel checkerboard electrode arrangement. The physical structure is refined using a design automation process which utilises finite element analysis (FEA) and design optimisation tools that adjust the design variables until suitable design requirements are met. Finally, processing steps are outlined for the fabrication of the device using a modified, commercially available polysilicon MEMS process.

This thesis presents an adaptive model reference controller for a highly maneuverable high performance aircraft, in particular, a modified F18. An adaptive controller is developed to maneuver an aircraft at a high angle of attack. Thus, the aircraft is required to fly over a highly nonlinear flight regime. The adaptive controller presented in this thesis can be viewed as a combination of a linear and a nonlinear controller. Around a fixed flight condition the adaptive controller converges to a linear controller; however, the controller remains a nonlinear controller during maneuvers. The contributions of this thesis lie in two areas. The first area is in control. A successful application of linear adaptive control is presented for a highly nonlinear system. A new method is used to generate the reference trajectory. The reference model uses output feedback to improve the reference trajectory. It is shown that this improvement is necessary because of the control limitations. This work is also important to the control of highly maneuverable high performance aircraft. A successful adaptive controller has been developed to rapidly maneuver an aircraft to a high angle of attack. The main focus of this thesis is adaptive control. / Graduation date: 1993

Generative Multimedia (GM) applications are an increasingly popular way to implement interactive media performances. Our contributions include creating a metric for evaluating Generative Multimedia performances, designing a model for accepting perceiver preferences, and using those preferences to adapt GM performances. The metric used is imprecision, which is the ratio of the actual computation time of a GM element to the computation time of a complete version of that GM element. By taking a perceiver's preferences into account when making adaptation decisions, applications can produce GM performances that meet soft real-time and resource constraints while allocating imprecision to the GM elements the perceiver least cares about. Compared to other approaches, perceiver-directed imprecision best allocates impreciseness while minimizing delay.