When hostile missile raids are launched, protecting allied assets requires that many targets be tracked simultaneously. In these raids, it is possible that the number of missiles could outnumber the sensors available to measure them. In these situations, communication between sensors can be utilized along with dynamic task planning to increase the amount of knowledge available concerning these missiles. Since any allied decisions must depend on the knowledge available from the sensors, it follows that improving the overall knowledge will improve the ability of allies to protect their assets through improved decision making. The goal of the this research effort is to create a Sensor Resource Management (SRM) algorithm to optimize the information available during these missile raids, as well as strengthening the simulation framework required to evaluate the performance of the SRM. The SRM must be capable of near-real-time run time so that it could potentially be deployed in a real-world system. The SRM must be capable of providing time-varying assignments to sensors, allowing more than one target to be observed by a single sensor. The SRM must predict measurements based on sensor models to assess the potential information gain by each assignment. Using these predictions, an optimal allocation of all sensors must be constructed. The initial simulation, upon which this work was built, was capable of simulating a set number of missiles launched simultaneously, providing appropriate charts to display the accuracy of knowledge on each target as well as their predicted impact locations. Communication delays are implemented within the simulation, and sensor models are refined. In refining the sensor models, they are given geometric limitations such as range and viewing angles. Additionally, simulated measurements incorporate geometric considerations to provide more realistic values. The SRM is also improved to account for the details added to the simulation. These improvements include creating assignment schedules and allowing a time-varying numbers of targets. The resulting simulation and SRM are presented, and potential future work is discussed. / text

Fringe projection is a commonly used optical technique for measuring the shapes of objects with dimensions of up to about 1 m across. There are however many instances in the aerospace and automotive industries where it would be desirable to extend the benefits of the technique (e.g., high temporal and spatial sampling rates, non-contacting measurements) to much larger measurement volumes. This thesis describes a process that has been developed to allow the creation of a large global measurement volume from two or more independent shape measurement systems. A new 3-D large volume calibration artefact, together with a hexapod positioning stage, have been designed and manufactured to allow calibration of volumes of up to 3 x 1 x 1 m3. The artefact was built from carbon fibre composite tubes, chrome steel spheres, and mild steel end caps with rare earth rod magnets. The major advantage over other commonly used artefacts is the dimensionally stable relationship between features spanning multiple individual measurement volumes, thereby allowing calibration of several scanners within a global coordinate system, even when they have non-overlapping fields of view. The calibration artefact is modular, providing the scalability needed to address still larger measurement volumes and volumes of different geometries. Both it and the translation stage are easy to transport and to assemble on site. The artefact also provides traceabitity for calibration through independent measurements on a mechanical CMM. The dimensions of the assembled artefact have been found to be consistent with those of the individual tube lengths, demonstrating that gravitational distortion corrections are not needed for the artefact size considered here. Deformations due to thermal and hygral effects have also been experimentally quantified. The thesis describes the complete calibration procedure: large volume calibration artefact design, manufacture and testing; initial estimation of the sensor geometry parameters; processing of the calibration data from manually selected regions-of-interest (ROI) of the artefact features; artefact pose estimation; automated control point selection, and finally bundle adjustment. An accuracy of one part in 17 000 of the global measurement volume diagonal was achieved and verified.

Lathes are frequently used in industrial production. It is an important parameter to calculate the force exerted by the cutter head on the raw material. Knowing the force acting on the cutting tool will aid in predicting the displacement of the cutting edge as well as predict displacement of the workpiece. The main purpose of this paper is to find a way to calculate the force exerted on the cutting tool tip. The magnitude of the tooltip force is estimated without the use of a force sensor. Instead, strain sensors are used to collect strain signals, and acceleration sensors are used to collect acceleration signals. Combine these two signals to calculate the magnitude of force. The force-strain frequency response function is calculated. The force-strain FRF acts as a bridge connecting force and strain signals. Calculate the input force signal on the cutting tool tip using the strain signal. In this way, is available to obtain the force time-image. Changes in force can be predicted by looking for force-time laws. In this thesis using MATLAB software for simulation and actual experimental measurements. Verify the reliability of the calculation method. The method and MATLAB code for calculating force-strain FRF are researched and written. Simulate the cutting tool input-output model in MATLAB. Combined with the actual experimental measurement results, the accuracy and limitations of this calculation method are analyzed. Discuss directions for future work.

A multiple-sensor optical shape measurement system (SMS) based on the principle of white-light fringe projection has been developed and commercialised by Loughborough University and Phase Vision Ltd for over 10 years. The use of the temporal phase unwrapping technique allows precise and dense shape measurements of complex surfaces; and the photogrammetry-based calibration technique offers the ability to calibrate multiple sensors simultaneously in order to achieve 360° measurement coverage. Nevertheless, to enhance the applicability of the SMS in industrial environments, further developments are needed (i) to improve the calibration speed for quicker deployment, (ii) to broaden the application range from shape measurement to deformation field measurement, and (iii) to tackle practically-challenging surfaces of which specular components may disrupt the acquired data and result in spurious measurements. The calibration process typically requires manual positioning of an artefact (i.e., reference object) at many locations within the view of the sensors. This is not only timeconsuming but also complicated for an operator with average knowledge of metrology. This thesis introduces an automated artefact positioning system which enables automatic and optimised distribution of the artefacts, automatic prediction of their whereabouts to increase the artefact detection speed and robustness, and thereby greater overall calibration performance. This thesis also describes a novel technique that integrates the digital image correlation (DIC) technique into the present fringe projection SMS for the purpose of simultaneous shape and deformation field measurement. This combined technique offers three key advantages: (a) the ability to deal with geometrical discontinuities which are commonly present on mechanical surfaces and currently challenging to most deformation measurement methods, (b) the ability to measure 3D displacement fields with a basic single-camera single-projector SMS with no additional hardware components, and (c) the simple implementation on a multiple-sensor hardware platform to achieve complete coverage of large-scale and complex samples, with the resulting displacement fields automatically lying in a single global coordinate system. A displacement measurement accuracy of ≃ 1/12,000 of the measurement volume, which is comparable to that of an industry-standard DIC system, has been achieved. The applications of this novel technique to several structural tests of aircraft wing panels on-site at the research centre of Airbus UK in Filton are also presented. Mechanical components with shiny surface finish and complex geometry may introduce another challenge to present fringe projection techniques. In certain circumstances, multiple reflections of the projected fringes on an object surface may cause ambiguity in the phase estimation process and result in incorrect coordinate measurements. This thesis presents a new technique which adopts a Fourier domain ranging (FDR) method to correctly identifying multiple phase signals and enables unambiguous triangulation for a measured coordinate. Experiments of the new FDR technique on various types of surfaces have shown promising results as compared to the traditional phase unwrapping techniques.

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The Internet of Things (IoT) is an umbrella term for smart things connected to the Internet. Connected sensors may be used to the benefit of smart building management systems. This thesis describes the development of a sensor based building management system prototype, lightweight enough to run on a single network camera. The focus of the research was investigating if the system prototype was scalable, and capable of storing and analyzing data gathered from a large amount of sensors relevant to the field of building management. The prototype was developed through a five-stage systems development process, and evaluated using simulations and case studies. The finished prototype was able to gather and store data from a few hundred real-time sensors using limited hardware. Tests showed that the network camera should be capable of managing at least 100 sensors. The system itself is scalable with the use of more powerful hardware. However, using a distributed architecture would be preferable if more sensors are required. This could be achieved by creating a distributed network of cameras, where each camera manages its own set of sensors. This could both increase scalability and make the system more robust and reliable.

Indiana University-Purdue University Indianapolis (IUPUI) / A novel method of power management and sequential monitoring of several sensors is proposed in this work. Application specific integrated circuits (ASICs) consisting of analog and digital sub-systems forming a system on chip (SoC) has been designed using complementary metal-oxide-semiconductor (CMOS) technology. The analog sub-system comprises the sensor-drivers that convert the input voltage variations to output pulse-frequency. The digital sub-system includes the system management unit (SMU), counter, and shift register modules. This performs the power-usagemanagement, sensor-sequence-control, and output-data-frame-generation functions. The SMU is the key unit within the digital sub-system is that enables or disables a sensor. It captures the pulse waves from a sensor for 3 clocks out of a 16-clock cycle, and transmits the signal to the counter modules. As a result, the analog sub-system is at on-state for only 3/16th fraction (18 %) of the time, leading to reduced power consumption. Three cycles is an optimal number selected for the presented design as the system is unstable with less than 3 cycles and higher clock cycles results in increased power consumption. However, the system can achieve both higher sensitivity and better stability with increased on-state clock cycles. A current-starved-ring-oscillator generates pulse waves that depend on the sensor input parameter. By counting the number of pulses of a sensor-driver in one clock cycle, a sensor input parameter is converted to digital. The digital sub-system constructs a 16-bit frame consisting of 8-bit sensor data, start and stop bits, and a parity bit. Ring oscillators that drive capacitance and resistance-based sensors use an arrangement of delay elements with two levels of control voltages. A bias unit which provides these two levels of control voltages consists of CMOS cascade current mirror to maximize voltage swing for control voltage level swings which give the oscillator wider tuning range and lower temperature induced variations. The ring oscillator was simulated separately for 250 nm and 180 nm CMOS technologies. The simulation results show that when the input voltage of the oscillator is changed by 1 V, the output frequency changes linearly by 440 MHz for 180 nm technology and 206 MHz for 250 nm technology. In a separate design, a temperature sensitive ring oscillator with symmetrical load and temperature dependent input voltage was implemented. When the temperature in the simulation model was varied from -50C to 100C the oscillator output frequency reduced by 510 MHz for the 250 nm and by 810 MHz for 180 nm CMOS technologies, respectively. The presented system does not include memory unit, thus, the captured sensor data has to be instantaneously transmitted to a remote station, e.g. end user interface. This may result in a loss of sensor data in an event of loss of communication link with the remote station. In addition, the presented design does not include transmitter and receiver modules, and thus necessitates the use of separate modules for the transfer of the data.