Identification of aircrew tasks for using direct voice input (DVI) to reduce pilot workload in the AH-64D Apache Longbow

Advances in helicopter design continue to saturate the pilot\u27s visual channel and produce remarkable increases in cognitive workload for the pilot. This study investigates the potential implementation of Direct Voice Input (DVI) as an alternative control for interacting with onboard systems of the AH-64D Apache, in an attempt to reduce pilot workload during a hands on the controls and eyes out condition. The intent is to identify AH-64D cockpit tasks performed through Multi Purpose Displays (MPDs) that when converted to DVI will provide the greatest reduction in task execution time and workload. A brief description of applicable AH-64D audio and visual displays are provided. A review of current trends in state-of-the-art voice recognition technology is presented, as well as previous and current voice input cockpit identification studies. To identify tasks in the AH-64D, a methodology was developed consisting of a detailed analysis of the aircraft\u27s mission and on-board systems. A pilot questionnaire was developed and administered to operational AH-64D pilots to assess their input on DVI implementation. Findings indicate DVI would be most useful for displaying selected MPD pages and performing tasks pertaining to the Tactical Situation Display (TSD), weapons, and communications. Six of the candidate DVI tasks were performed in the AH-64D simulator using the manual input method and a simulated voice input method. Two different pilots made objective and subjective evaluations. Task execution times and workload rating were lower using a simulated means of voice input. Overall, DVI shows limited potential for workload reduction and warrants further simulator testing before proceeding to the flight environment

Ground-based synthetic aperture radar (GBSAR) interferometry for deformation monitoring

Ph. D ThesisGround-based synthetic aperture radar (GBSAR), together with interferometry, represents a powerful tool for deformation monitoring. GBSAR has inherent flexibility, allowing data to be collected with adjustable temporal resolutions through either continuous or discontinuous mode. The goal of this research is to develop a framework to effectively utilise GBSAR for deformation monitoring in both modes, with the emphasis on accuracy, robustness, and real-time capability. To achieve this goal, advanced Interferometric SAR (InSAR) processing algorithms have been proposed to address existing issues in conventional interferometry for GBSAR deformation monitoring. The proposed interferometric algorithms include a new non-local method for the accurate estimation of coherence and interferometric phase, a new approach to selecting coherent pixels with the aim of maximising the density of selected pixels and optimizing the reliability of time series analysis, and a rigorous model for the correction of atmospheric and repositioning errors. On the basis of these algorithms, two complete interferometric processing chains have been developed: one for continuous and the other for discontinuous GBSAR deformation monitoring. The continuous chain is able to process infinite incoming images in real time and extract the evolution of surface movements through temporally coherent pixels. The discontinuous chain integrates additional automatic coregistration of images and correction of repositioning errors between different campaigns. Successful deformation monitoring applications have been completed, including three continuous (a dune, a bridge, and a coastal cliff) and one discontinuous (a hillside), which have demonstrated the feasibility and effectiveness of the presented algorithms and chains for high-accuracy GBSAR interferometric measurement. Significant deformation signals were detected from the three continuous applications and no deformation from the discontinuous. The achieved results are justified quantitatively via a defined precision indicator for the time series estimation and validated qualitatively via a priori knowledge of these observing sites.China Scholarship Council (CSC), Newcastle Universit