دانلود رایگان مقاله انگلیسی بهینه سازی سیستم سنسور برای رسیدن به اهداف قابلیت اطمینان - الزویر 2018

ABSTRACT

In this work, we show the influence of sensor system measurement uncertainties to sensor system reliability and ways to meet reliability targets. A general model to handle measurement uncertainties is defined and the according influence to reliability is presented, which is defined as probability of meeting specification requirements. Initial step is to optimize sensor systems concerning lowest influences of sensor system parameter fluctuations to the measurement uncertainty using statistical optimization methodologies. In case the influence of unknown nuisance parameters cannot be sufficiently suppressed, such parameters may be additionally measured in order to further reduce measurement uncertainties. The remaining uncertainties are again addressed using statistical optimization methodologies. Finally, measurement uncertainty also affects the reliability of such a system. For sensor systems in safety critical applications it may thus be required to include measures such as redundancy. This is also included in the investigations. Further examples for explained optimization methodologies of measurement uncertainty reduction are presented.

Conclusion

In this work, we showed several possibilities to reduce measurement uncertainties to fulfill reliability requirements. This can be done by statistical methods applying optimal design of experiment methodologies. Statistical optimizations benefit from the fact that we do not need to measure the influencing parameter but design the sensor system in a way that external influencing parameters have lowest possible effects. In case of further reducing the uncertainties correlations of influencing parameters can be used. The compensation of influencing parameters can be done by measure them and use its values for reduction of their contribution to measurement uncertainties. It could also be shown how calibration and test uncertainties influence the sensor system in the same way as implemented sensor system uncertainties and need to be taken into account in the same way when optimizing sensor systems. Additionally optimizations of reliably working safety mechanisms of safety critical sensor systems can be performed using the statistical considerations of calculating probabilities for not detecting a fault as well as raising false alarms. These reduced uncertainties increase the reliability of these sensor systems to fulfill all the required specifications.