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A novel three-finger IPMC gripper for microscale applicationsYun, Kwan Soo 17 September 2007 (has links)
Smart materials have been widely used for control actuation. A robotic hand can
be equipped with artificial tendons and sensors for the operation of its various joints
mimicking human-hand motions. The motors in the robotic hand could be replaced with
novel electroactive-polymer (EAP) actuators. In the three-finger gripper proposed in this
paper, each finger can be actuated individually so that dexterous handling is possible,
allowing precise manipulation.
In this dissertation, a microscale position-control system using a novel EAP is
presented. A third-order model was developed based on the system identification of the
EAP actuator with an AutoRegresive Moving Average with eXogenous input (ARMAX)
method using a chirp signal input from 0.01 Hz to 1 Hz limited to 7 ñ V. With the
developed plant model, a digital PID (proportional-integral-derivative) controller was
designed with an integrator anti-windup scheme. Test results on macro (0.8-mm) and
micro (50-üm) step responses of the EAP actuator are provided in this dissertation and its
position tracking capability is demonstrated. The overshoot decreased from 79.7% to 37.1%, and the control effort decreased by 16.3%. The settling time decreased from 1.79
s to 1.61 s. The controller with the anti-windup scheme effectively reduced the
degradation in the system performance due to actuator saturation. EAP microgrippers
based on the control scheme presented in this paper will have significant applications
including picking-and-placing micro-sized objects or as medical instruments.
To develop model-based control laws, we introduced an approximated linear
model that represents the electromechanical behavior of the gripper fingers. Several chirp
voltage signal inputs were applied to excite the IPMC (ionic polymer metal composite)
fingers in the interesting frequency range of [0.01 Hz, 5 Hz] for 40 s at a sampling
frequency of 250 Hz. The approximated linear Box-Jenkins (BJ) model was well matched
with the model obtained using a stochastic power-spectral method. With feedback control,
the large overshoot, rise time, and settling time associated with the inherent material
properties were reduced. The motions of the IPMC fingers in the microgripper were
coordinated to pick, move, and release a macro- or micro-part. The precise manipulation
of this three-finger gripper was successfully demonstrated with experimental closed-loop
responses.
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An integrated analog controller for signal based A/D conversionChen, Hsin-Yu 11 August 2008 (has links)
Abstract:
This thesis is concerned with the acquisition of body signals using a sampling system. A typical
application is the recording of the electrocardiogram (ECG). It is proposed to sample the input
signal at different rates, depending on the momentary signal content. If the input signal has large
voltage variation, it is sampled at a high rate. During periods of small variation, the signal is
sampled at a lower frequency to save both memory and power. An analog controller to control the
clock rate is proposed and implemented. The analog controller decides the sample frequency (high
rate or low rate) depending on the input signal. The analysis of the proposed system is presented in
this thesis. Furthermore, a working prototype is implemented using discrete components on a PCB.
The measured results show a significant reduction in the average sample frequency and data rate of
50% and 35%, respectively. Finally, the critical analog circuit blocks of the system suitable for
integration on chip are proposed and implemented in a 0.35£gm CMOS process. Measured results
are reported to confirm the functionality of the blocks.
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Embedded microcomputer controller industry management strategy discussion --- Take AWTech Corporation as the exampleHsu, Ching-cheng 14 August 2008 (has links)
Embedded microcomputer controller application coverage is widespread, for example: Defense industry, aerospace industry, industrial automation, domestic electric appliances, vehicle with electronic, consumption electronic products and so on, embedded microcomputer relative and general computer difference, is essential and each different profession application unifies, must have the specialized ability, is more than outside the general computer's knowledge, researches and develops the personnel often is each application domain expert, also in accordance to uses the domain the difference, this industry fills is competing, the opportunity and the innovation, also belongs to a dispersion industry, even if has the mainstream architecture, but is in no way by the minority company or the product can corner the market. Taiwan electron industry's on middle and lower reaches supplies the chain to be complete, compares in the overseas manufacturer has the relative superiority, the prospects for development favors as before, in the terminal product system construction, the embedded microcomputer controller belongs to the spare part, the system assembles the entrepreneur extremely little to ford into the design and the manufacture, also, because its application stratification plane is broad, product and technical high dispersion, and few diverse and the guest makes the characteristic, suits the small scale highly specialized technology corporate growth.
Because this industry has the quantity body to subscribe makes, diverse and so on characteristics few, regards as throughout in the electronic related industry the high value added the tally company market, in recent years the applied technology universalized gradually, the market joined in the numerous competitors competes the influence, the manufacturer faced with the impact and the growth pressure, in the past concentrated only ¡§the technology¡¨ and ¡§the quality¡¨ the maintenance, has been unable to satisfy multiplex the market demand; The management essence lies in the activity and the layout, how does the thorough analysis market understand the customer demand, utilizes the limited enterprise resources and the energy, the strengthened enterprise competitive power, the fixed industry trend of development, unifies the research and development, the manufacture closely and sells this tripartite core competence , draws up the best whole management strategy, is the operator urgently must understanding the answer.
Goal of this research, in discussion case AWTech Corporation locates in the industry, its characteristic, present situation, the tendency and have the core competencies; After the analysis understood market, product and customer, induces case AWTech Corporation the resources and ability which has in this industry, the enterprise external environment opportunity and the threat with the enterprise interior superior inferiority, innovates and the unique way, draws up the effective feasible whole management development strategy, achieves the internationalization goal in the competitive market.
The research the main conclusion is as follows:
1. The undertaking stage's success cannot guarantee that the future management can also succeed continually, essential consideration factors and so on environmental factor, market demand, product localization, customer behavior pattern, at the right moment revise transport business strategy and the development direction.
2. The strengthened company's core competencies, the centralized resources choose the realistic product and the market are the development direction, makes the most effective use the resources, and will complete the duty carries out accurately, gains the biggest benefit.
3. The internationalization operation viewpoint consideration, draws up the management development strategy, expands steady the enterprise domain.
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Organisational structure influences on the controller roles in Sweden : A cross case study between six organisations in the clothing industryKristofersson, Ann, Falk, Johanna, Jonson, Christofer January 2008 (has links)
<p>Background: Increasing competition has led to a large interest for management control and leadership in Sweden. The controller’s role has changed from just including number crunching tasks to become more market and customer oriented. Therefore the use of controllers today is increasing within Swedish organisations. The role incorporates involvement in management decision making process. Organisational structure affects the work role as well as the location of the employee within an organisation.</p><p>Purpose: Our objective is to explore how and why the controller roles in Sweden differ from one organisation to another. To make it more interesting a second dimension, organisational structure, is included. We aim to develop guidelines that can provide useful insights to already existing theory. A mix between the inductive and the deductive approach is used.</p><p>Method: A qualitative cross case study has been performed where controllers from six different organisations present in the Swedish market have been interviewed. The organisations are operating in the clothing industry. Generalisation is not emphasised rather the uniqueness of each case is highlighted. A cross case analysis was performed to reveal differences and similarities between the cases.</p><p>Conclusion: We have found that a divisionalised structure where the subsidiary is relatively large results in decentralised decision making. The controller belongs to an own function located straight below the CEO and is titled business controller. This controller is recognised to be an involved controller. The involved controller was also found in organisations where some influences of the machine bureaucracy were apparent. If the controller belongs to the finance function it is likely that he/she performs accounting related tasks and the controller role is recognised to be the independent controller. If the controller belongs to the purchase function and the adhocracy is found the split controller role is evident. To prevent confusion we suggest that more controller titles should be added and the title should also communicate what tasks and responsibilities that correspond to the role. If you belong to the finance function an appropriate title would be accounting controller. By looking at the organisational structure it is possible to get guidance for what the role incorporates and what tasks and responsibilities that can be expected. Variance will always apply since there are no rules and regulations for financial control.</p>
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Data Requirements for a Look-Ahead SystemHolma, Erik January 2007 (has links)
<p>Look ahead cruise control deals with the concept of using recorded topographic road data combined with a GPS to control vehicle speed. The purpose of this is to save fuel without a change in travel time for a given road. This thesis explores the sensitivity of different disturbances for look ahead systems. Two different systems are investigated, one using a simple precalculated speed trajectory without feedback and the second based upon a model predictive control scheme with dynamic programming as optimizing algorithm.</p><p>Defect input data like bad positioning, disturbed angle data, faults in mass estimation and wrong wheel radius are discussed in this thesis. Also some investigations of errors in the environmental model for the systems are done. Simulations over real road profiles with two different types of quantization of the road slope data are done. Results from quantization of the angle data in the system are important since quantization will be unavoidable in an implementation of a topographic road map.</p><p>The results from the simulations shows that disturbance of the fictive road profiles used results in quite large deviations from the optimal case. For the recorded real road sections however the differences are close to zero. Finally conclusions of how large deviations from real world data a look ahead system can tolerate are drawn.</p>
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FPGA design of a controller for a CAN controller. / FPGA design av en kontrollenhet för en CAN-kontrollenhet.Andersson, Robby January 2003 (has links)
<p>This diploma work describes how an FPGA is designed to control a CAN controller. It describes the different tools used when working with Actel’s design tools and the sequence of work applied. It gives a short overview of a multiplexer, the CAN bus, an analog/digital-converter and some more information on the actual FPGA. It also brings up the design process of the FPGA, planning, coding, simulating, testing and finally programming the FPGA. The different parts implemented in the FPGA are a shift-register and two state- machines that are connected with each other. They work together to control the SJA1000 CAN controller made by Philips. They also receive data from the analog/digital-converter that they forward onwards to the CAN controller that forward the data on the CAN bus.</p>
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A Study on Lane-Change Recognition Using Support Vector MachineDeng, Weiping 01 January 2013 (has links)
This research focuses primary on recognition of lane-change behaviors using support vector machines (SVMs). Previous research and statistical results show that the vast majority of motor vehicle accidents are caused by driver behavior and errors. Therefore, the interpretation and evaluation of driver behavior is important for road safety analysis and improvement. The main limit to understanding driver behavior is the data availability. In particular, a full-scale lane-change data set is difficult to collect in a real traffic environment because of the safety and cost issues. Considering the data demands of the recognition model development and the obstacles of field data collection, data were collected from two aspects: simulation data and the field data. To obtain field data, an in-vehicle data recorder (IVDR) that integrates a Global Positioning System (GPS) and Inertial Measurement Unit (IMU) are developed to collect data on speed, position, attitude, acceleration, etc. To obtain simulation data, a lane-change simulation with a speed controller and a trajectory tracking controller with preview ability were developed, and sufficient lane-change data were generated. Proportional-Integral-Derivative (PID) control is applied to the speed controller and trajectory tracking controller.
Simulation data were divided into two classes: dual lane-change data and single lane-change data; field data were further divided as single lane-change and non-lane-change data. Two-class and three-class classification SVM model are trained by simulation data and field data, and the model parameters were optimized by Genetic Algorithm (GA). A radial basis function and polynomial kernel functions were found that suitable for this recognition task. The recognition results indicate that, the SVM model trained by simulation data and non-lane-change data can correctly classify up to 85 percent of single lane-change field data.
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Control algorithms and flight software framework for a spacecraft guidance navigation and control systemZhang, Jing 10 February 2012 (has links)
This thesis presents a comparison of controller designs and a system software design for a general Guidance, Navigation and Control (GNC) system. The first part of the thesis investigates four control algorithms based on Lyapunov Direct Method in conjunction with sliding mode and adaptive control. These algorithms address three practical issues in controller design: maximum actuation limitation, external disturbances, and imperfect dynamic models. Each of the algorithms is proven to be globally asymptotically stable within its constraints. A simulation is then used to model a cube-satellite attitude maneuver using each of the controllers to evaluate its performance. The second part of this thesis discusses the development of a high-level flight software architecture capable of handling common tasks, including ground station communication and attitude maneuvers, as well as power or device failures. / text
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Joint color-depth restoration with kinect depth camera and its applications to image-based rendering and hand gesture recognitionWang, Chong, 王翀 January 2014 (has links)
abstract / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
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Projektcontrollerns roll vid styrning av anläggningsprojekt – en studie inom ABB ABSundin, Lotta, Cehic, Sanela January 2008 (has links)
Syftet med denna uppsats var att beskriva och analysera projektcontrollerns roll inom de projektintensiva enheterna FACTS och Substations på ABB AB. Studien bygger på tre personliga intervjuer utförda med projektcontrollers samt sex platsannonser som analyserats. Teorin består av två delar, dels projektaspekten och dels controlleraspekten. Första delen behandlar vad ett projekt är och vad det innebär att jobb i projektform. Andra delen, controlleraspekten, handlar om controllers ursprung kontra dagens roll och dess arbetsuppgifter. I empirin presenteras intervjuerna samt en sammanställning över platsannonser på projektcontroller. Därefter presenteras analysen av resultat som framkom genom intervjuerna och platsannonserna. Författarna utgår från rubrikerna projektstyrning och projektcontrollers roll. Studiens analys sammankopplas med den valda teorin, med utgångspunkt i studiens problemställning. Ett projekt kan variera i storlek och komplexitet likaså antalet projekt som ABB AB driver. Tids och kostnadsaspekten är väldigt viktig, likaså kontakten med kunden. ”Erfarenhetsåtervinning” innebär att utvärdering sker på vad som gått bra och mindre bra. Allt för att lära sig och bli bättre till nästa projekt. Projektcontroller är något som en ekonom kan avancera sig upp genom företaget och dennes roll är vad individen själv gör den till. Företagen anger vissa kvalifikationer som jobben kräver, men slutligen är det individen själv, som med egen erfarenhet och intressen, som formar rollen.
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