Tablet User Interface Evaluation for a Portable Ultrasound System and Real time Doppler SpectrumProcessing

In this thesis, real time Doppler spectrum processing and Tablet user interface evaluation for portable ultrasound system is done.In most ultrasound machines, fast fourier transform and other spectral processing requires a specialized hardware, which is costly. In order to have a low cost and portable ultrasound device for application in rural areas, a tablet ultrasound system can be developed. The cost of such a device can be minimized by doing as much real-time processing as possible on the tablet. In the thesis,Doppler spectrum processing and visualization is implemented using various techniques for application on a tablet user interface. The spectral properties are properly designed and the required components of the spectrum rendering window are fully developed. Various user control systems are also developed to allow user interactivity.Tablet user interface evaluation was conducted to assess the usability of the user interface for intended end users (midwives). Before conducting the evaluation, some improvements were performed to the prototype user interface. The usability evaluation of the user interface was conducted by giving usability test task over a group of midwives and evaluated using various usability evaluation methods. By employing these methods, it was possible to measure the typical usability goals such as efficiency, task completion success rate and satisfaction of the users. The analysed results show that all the midwives have achieved high task completion success rate and good task completion time, which is acceptable and most of the users are satisfied with the application.Due to some facility limitations at the beginning of the thesis work, a pilot usability study and its subsequent user interface improvement, which were planned at the beginning, are not included as part of this thesis