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Konstruktion av Industriellt Vibrationsmätningssystem med signalbehandling baserad på Digitala Vågfilter av Lattice-struktur / Construction of Industrial Vibration Measurement System with signal-processing based on Lattice Wave Digital filter structuresTegelid, Simon, Åström, Jonas January 2010 (has links)
<p>In this bachelor thesis a complete prototype of an industrial vibration measurement platform has been developed. By measuring a number of variables such as acceleration, temperature and speed conclusions can be drawn on machinery health. The aim is to evaluate hardware and software solutions for a possible future product. Based on a requirement specification a proper hardware design has be developed. The hardware consists of a four-layer PCB with an ARM Cortex-M3 microcontroller and about 250 other components. The PCB was designed, assembled, tested and finally housed in a box. Measures have been taken to protect the prototype against external disturbances such as inappropriate supply voltages and transients on the input stages.Software has been written for the microcontroller to perform the various measurements required by the prototype. These include RMS, integration and filtering. Special attention was paid to the latter by implementing filters based on lattice wave digital structures. This structure results in a very efficient implementation. Consideration is taken to be able to generate arbitrary filters independent of the characteristics and design method. To save time the microcontroller implements all the algorithms without any floating point numbers.Furthermore, both hardware and software are adapted for future industrial use. The finished prototype supports a number of communication interfaces in which Modbus (RS-485) and current loop communication can be mentioned.The final result is a very good performing platform with strong future potential.The work was commissioned by the consulting firm Syncore Technologies AB at their office in Mjärdevi, Linköping. The project has, in total, taken 10 weeks and occurred during spring 2010.In this bachelor thesis a complete prototype of an industrial vibration measurement platform has been developed. By measuring a number of variables such as acceleration, temperature and speed conclusions can be drawn on machinery health. The aim is to evaluate hardware and software solutions for a possible future product. Based on a requirement specification a proper hardware design has be developed. The hardware consists of a four-layer PCB with an ARM Cortex-M3 microcontroller and about 250 other components. The PCB was designed, assembled, tested and finally housed in a box. Measures have been taken to protect the prototype against external disturbances such as inappropriate supply voltages and transients on the input stages.Software has been written for the microcontroller to perform the various measurements required by the prototype. These include RMS, integration and filtering. Special attention was paid to the latter by implementing filters based on lattice wave digital structures. This structure results in a very efficient implementation. Consideration is taken to be able to generate arbitrary filters independent of the characteristics and design method. To save time the microcontroller implements all the algorithms without any floating point numbers.Furthermore, both hardware and software are adapted for future industrial use. The finished prototype supports a number of communication interfaces in which Modbus (RS-485) and current loop communication can be mentioned.The final result is a very good performing platform with strong future potential.The work was commissioned by the consulting firm Syncore Technologies AB at their office in Mjärdevi, Linköping. The project has, in total, taken 10 weeks and occurred during spring 2010.</p>
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Konstruktion av Industriellt Vibrationsmätningssystem med signalbehandling baserad på Digitala Vågfilter av Lattice-struktur / Construction of Industrial Vibration Measurement System with signal-processing based on Lattice Wave Digital filter structuresTegelid, Simon, Åström, Jonas January 2010 (has links)
In this bachelor thesis a complete prototype of an industrial vibration measurement platform has been developed. By measuring a number of variables such as acceleration, temperature and speed conclusions can be drawn on machinery health. The aim is to evaluate hardware and software solutions for a possible future product. Based on a requirement specification a proper hardware design has be developed. The hardware consists of a four-layer PCB with an ARM Cortex-M3 microcontroller and about 250 other components. The PCB was designed, assembled, tested and finally housed in a box. Measures have been taken to protect the prototype against external disturbances such as inappropriate supply voltages and transients on the input stages.Software has been written for the microcontroller to perform the various measurements required by the prototype. These include RMS, integration and filtering. Special attention was paid to the latter by implementing filters based on lattice wave digital structures. This structure results in a very efficient implementation. Consideration is taken to be able to generate arbitrary filters independent of the characteristics and design method. To save time the microcontroller implements all the algorithms without any floating point numbers.Furthermore, both hardware and software are adapted for future industrial use. The finished prototype supports a number of communication interfaces in which Modbus (RS-485) and current loop communication can be mentioned.The final result is a very good performing platform with strong future potential.The work was commissioned by the consulting firm Syncore Technologies AB at their office in Mjärdevi, Linköping. The project has, in total, taken 10 weeks and occurred during spring 2010.In this bachelor thesis a complete prototype of an industrial vibration measurement platform has been developed. By measuring a number of variables such as acceleration, temperature and speed conclusions can be drawn on machinery health. The aim is to evaluate hardware and software solutions for a possible future product. Based on a requirement specification a proper hardware design has be developed. The hardware consists of a four-layer PCB with an ARM Cortex-M3 microcontroller and about 250 other components. The PCB was designed, assembled, tested and finally housed in a box. Measures have been taken to protect the prototype against external disturbances such as inappropriate supply voltages and transients on the input stages.Software has been written for the microcontroller to perform the various measurements required by the prototype. These include RMS, integration and filtering. Special attention was paid to the latter by implementing filters based on lattice wave digital structures. This structure results in a very efficient implementation. Consideration is taken to be able to generate arbitrary filters independent of the characteristics and design method. To save time the microcontroller implements all the algorithms without any floating point numbers.Furthermore, both hardware and software are adapted for future industrial use. The finished prototype supports a number of communication interfaces in which Modbus (RS-485) and current loop communication can be mentioned.The final result is a very good performing platform with strong future potential.The work was commissioned by the consulting firm Syncore Technologies AB at their office in Mjärdevi, Linköping. The project has, in total, taken 10 weeks and occurred during spring 2010.
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Konstruktion och utvärdering av Current Conveyors / Construction and evaluation of Current ConveyorsJonasson, Anders January 2003 (has links)
Normally the operational amplifier is used as a component in active filter design. The goal for future components in filter design is large bandwith and the use of low supply voltages. The use of current-mode instead of voltage-mode circuits gets a step closer to the required performance. A component that use current as the signal conveying part is the current conveyor. In this report a comparative study between two current conveyor structures of second generation (CCII) is performed. The most suited is later implemented and simulated using the CMOS process AMS.C035. The component is also tested in a continuous-time elliptic low-pass filter of leapfrog type. The filter does not behave as it should. However, better performance can be obtained by redesigning the current conveyor.
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1MHz Bandwidth Switched-Current Sigma Delta ModulatorChen, Chih-hung 01 September 2010 (has links)
The thesis proposes an integrator with an OPAMP in the feedback loop to fulfill 1MHz bandwidth SI Sigma Delta modulator. The OPAMP is used to pull down the input impedance and get high speed and high resolution. Oversampling and noise shaping are the two keys of Sigma Delta modulator. In structure, multistage is helpful for depressing noises and we use three stages to fulfill this 4-order proposed Sigma Delta modulator.
The proposed Sigma Delta modulator uses TSMC 0.18£gm CMOS process and it is a 4-order and three stages SI Sigma Delta modulator. The sampling rate is 32MHz, bandwidth is 1MHz, and oversampling ratio is 16.
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The Study of Inter-firm Cooperationsin Information System Integration IndustriesChiang, Ru-Yu 24 July 2001 (has links)
With the coming of digital times, global competition resulted in every industry expanding their requirements in supply chain integration and enterprise resource planning. The importance of information system integration industries also increases with time. When all kind of industries continues to integrate supply chain and establish cooperative partnerships, trying to exploit cooperation to acquire more competencies in the market, we want to know whether the information system integration industries establish their cooperative relationship.
Therefore, our study tried to review the actives and relationship between integrators by the systems integration service process. Through the theory¡¦s guiding, we attend to induce the factors of inter-firm cooperation in system integration industries. We use multiple case study to design our research¡Aand select three cases to study. Semi-structural interview is used to collect needed data to understand the true cooperative relationship between integrators. According to transaction cost theory, resource-base theory and social exchange theory, we propose some theoretical propositions to guiding the real cases analysis.
The conclusions not only describe the real cooperation in Taiwan system integration industries, but also induce several factors of cooperative relationship between integrators, including product characteristics, transaction cost, resource, trust and guanxi. Moreover, the transaction cost is the most important element in the cooperative relationship between information system integrators.
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A 12-Bits/10.24MHz Sample Rate Switched-Current Sigma-Delta Modulator with OP-Amp Active IntegratorChao, Chun-Cheng 31 July 2008 (has links)
In this thesis, a switched-current sigma-delta modulator (SDM) with op-amp active integrator is proposed. The major study is focused on using the op-amp to reduce the input impedance for high speed and high solution and utilizes the dummy switch to decrease the clock feedthrough (CFT) error. We use a sample-and-hold circuit which consists of an op-amp active memory cell and a dummy switch circuit to implement the integrator. It is applied to the building blocks of SDM.
The modulator is a second order sigma-delta modulator. A current comparator transforms the current signal into digital voltage signal. A single-bit digital-to-analog (D/A) feedback circuit is used to convert the one-bit digital output to the SI integrator .The modulator is designed in the current mode technique.
The delta-sigma modulator simulates using the parameters of the TSMC 0.35£gm CMOS process. The simulation results show that the signal to noise plus distortion ratio (SNDR) is 72 dB, the sampling rate is 10.24MHz, the oversampling ratio is 128, the power consumption is 21mW, the dynamic range is about 70dB, and the power supply is 3.3V.
Furthermore, the circuit is verified by cadence-hspice simulation.
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Adaptive control for double-integrator class systems in the absence of velocity feedbackYang, Sungpil 23 April 2013 (has links)
This work considers formulation of new classes of adaptive controllers for double-integrator type systems where the underlying system parameters are uncertain and the complete state-vector is not available for feedback. Given the parameter uncertainty within the system model, a "separation principle" cannot generally be invoked towards an observer geared towards reconstruction of the full state vector using only measured variables.
In this report, controllers are designed for some important sub-classes of Euler-Lagrange type mechanical systems, where states are physically interpreted as position and velocity variables, and only the position part of the state vector is available as measured output. The typical approach to obtain velocity estimates using position interpolation (also known as dirty differentiation), is known to be strongly susceptible to measurement noise and therefore does not usually represent a robust option for feedback control implementation. The proposed control scheme achieves global asymptotic stability for system dynamics subject to the condition that velocity states appear within the governing dynamics in a linear fashion. This arguably restrictive condition is loosened for the special case of scalar system with friction non-linearity as is typical within hardware implementations. The objective is to study prototypical mechanical systems with non-linearity appearing in the velocity rate equations with the eventual applications envisioned towards the attitude control problem accounting for the gyroscopic non-linearity in the Euler rotational dynamics.
Based on classical certainty equivalence approaches for adaptive control, one cannot readily deal with cross terms associated with parameter estimates and unmeasured states in the Lyapunov function derivative in order to make the Lyapunov function negative definite or negative semi-definite. However, employing a new approach, this obstacle is shown in this report to be circumvented for scalar systems. In order to generalize the methodology for higher-order dynamics, a filtered state approach is used. Specifically, an auxiliary variable is introduced which plays an important role in determining restrictions on the control parameters and analyzing the stability. The proposed approach helps to overcome the uniform detectability obstacle. Additionally, this work can be applied to uncertain linear systems where independent control inputs are applied on each of the velocity state dynamics.
Lastly, the solution for the scalar is applied to the rotor speed control system and is extended to the case where Coulomb friction is considered in addition to viscous friction. Since a sign function can be approximated as a hyperbolic tangent, the tanh model is used for the Coulomb friction. A controller is developed with the assumption that the coefficients of these frictions are unknown. The proposed control is then verified with Educational Control Product Model 750 Control Moment Gyroscope, and the simulation and actual test results are compared. / text
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Energy Monitoring System for Security and Energy Management ApplicationsShariati, Sepideh 16 January 2013 (has links)
This thesis presents an energy monitoring system to measure energy consumption of software applications to support security and power management for embedded devices. The proposed system is composed of an Actel Fusion device and a custom designed energy measurement circuit. The Fusion device measures the voltage and the current of the target device at a defined sampling rate. The energy measurement circuit is designed as a current integrator over fixed intervals using the switched-capacitor integrator technique to store energy information of the target device within Fusion’s sampling intervals. This circuit is designed to accommodate the low sampling rate of the Fusion device.
Experimental results showed that the Fusion device allows the measurement of the energy of the target device at a minimum rate of 15 µs. The energy measurement circuit is implemented using the 65 nm CMOS technology. Simulation results showed that this circuit provides 91%~97% average energy measurement accuracy.
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Preservation of phase space structure in symplectic integration : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Mathematics at Massey University, Palmerston North, New ZealandO'Neale, Dion Robert James January 2009 (has links)
This thesis concerns the study of geometric numerical integrators and how they preserve phase space structures of Hamiltonian ordinary differential equations. We examine the invariant sets of differential equations and investigate which numerical integrators preserve these sets, and under what conditions. We prove that when periodic orbits of Hamiltonian differential equations are discretized by a symplectic integrator they are preserved in the numerical solution when the integrator step size is not resonant with the frequency of the periodic orbit. The preservation of periodic orbits is the result of a more general theorem which proves preservation of lower dimensional invariant tori from dimension zero (fixed points) up to full dimension (the same as the number of degrees of freedom for the differential equation). The proof involves first embedding the numerical trajectory in a non-autonomous flow and then applying a KAM type theorem for flows to achieve the result. This avoids having to prove a KAM type theorem directly for the symplectic map which is generally difficult to do. We also numerically investigate the break up of periodic orbits when the integrator's step size is resonant with the frequency of the orbit. We study the performance of trigonometric integrators applied to highly oscillatory Hamiltonian differential equations with constant frequency. We show that such integrators may not be as practical as was first thought since they suffer from higher order resonances and can perform poorly at preserving various properties of the di fferential equation. We show that, despite not being intended for such systems, the midpoint rule performs no worse than many of the trigonometric integrators, and indeed, better than some. Lastly, we present a numerical study of a Hamiltonian system consisting of two magnetic moments in an applied magnetic field. We investigate the effect of both the choice of integrator and the choice of coordinate system on the numerical solutions of the system. We show that by a good choice of integrator (in this case the generalised leapfrog method) one can preserve phase space structures of the system without having to resort to a change of coordinates that introduce a coordinate singularity.
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Internet of Things : How vendors can use IoT to achieve value creationEbrahiem, Waleed, Arif, Naveed January 2017 (has links)
The IoT (Internet of Things) is developing rapidly, as a result of that, the number of connected devices in Sweden has doubled every year. According to big companies like Ericsson, the estimated number of connected devices worldwide will be 50 billion in 2020. IoT, by itself, may be a relatively simple concept of connected devices and machines, but its implications are profound. For companies in Sweden which offer a broad range of non-connected tools and products, it is becoming increasingly important to adapt their products to IoT; adherence to IoT will warrant new developments which offer value-added services such as monitoring and remote control, etc. The primary research method employed for this thesis is a case study at a vendor company who today offers their customers non-connected tools. To be able to demonstrate the concept of IoT enhanced tools we create a conceptual framework and a prototype, which we present to our interviewees and use as a starting point for qualitative interviews. In this thesis, we want to know how vendors could benefit themselves by the use of IoT in their businesses. We formulated some research questions, being, based on a vendor’s perspective: why do they (vendors) need connected products; how can such products be made marketable to the customer; and what are the predicted benefits of IoT-connected products for the customers? The case study brings to light some issues dealing with the business model, service providing, data display and data security which every company should take into consideration before implementing IoT.
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