Task analysis for HMI design. Level of automation study of aircraft navigation functions

Advancements in technology have enabled increasingly sophisticated automation to be introduced into the flight decks of modern aircraft. Generally, this automation was added to accomplish worthy objectives such as reducing flight crew workload, adding additional capability, or increasing fuel economy. Automation is necessary due to the fact that not all of the functions required for mission accomplishment in today’s complex aircraft are within the capabilities of the unaided human operator, who lacks the sensory capacity to detect much of the information required for flight. To a large extent, these objectives have been achieved. Nevertheless, despite all the benefits from the increasing amounts of highly reliable automation, vulnerabilities do exist in flight crew management of automation and Situation Awareness (SA). Issues associated with flight crew management of automation include: • Pilot understanding of automation’s capabilities, limitations, modes, and operating principles and techniques. • Differing pilot decisions about the appropriate automation level to use or whether to turn automation on or off when they get into unusual or emergency situations. • Human-Machine Interfaces (HMIs) are not always easy to use, and this aspect could be problematic when pilots experience high workload situations. • Complex automation interfaces, large differences in automation philosophy and implementation among different aircraft types, and inadequate training also contribute to deficiencies in flight crew understanding of automation.

Quantitative analysis of pre- and post-operative valvular annulus deformations following valvular insufficiency

Valvular insufficiency is a growingly common valvular heart disease that frequently is associated with regurgitation. Atrioventricular incompetency can lead to overall ventricular and atrial enlargement, volume overload, heart impairment and, if not treated, can culminate in heart failure. With the advances in technology and the increasing interest in devices that have lower post-operative burden on patients, transcatheter mitral and tricuspid valve repair systems are going through a phase of rapid development and growing use. In this work, we aimed to quantitatively assess the morphology of mitral and tricuspid annuli in patients who underwent transcatheter valve repair with MitraClip/TriClip, before and after the intervention, using three-dimensional transoesophageal echocardiography images, in order to evaluate the geometrical changes of the annulus following the intervention. For our purposes, firstly, we implemented a tool for the visualization and navigation of the volumetric data across the cardiac cycle. Then, in order to track the annulus over the cardiac cycle, we extracted five rotational slices from the volume data, selected two initial points on each slice, and tracked these points across the cardiac cycle using KLT algorithm. In a first stage we led a parameters optimization for the tracking method, and we studied the sensitivity of the KLT algorithm to the initialization points, that are manually chosen by the user. In a second stage, we analysed 10 subjects (5 for mitral regurgitation and 5 for tricuspid regurgitation), tracking their annulus before and after valve repairment. In conclusion, we found in all our 10 subjects that immediately after the intervention there is a shortening of the major diameters of the valves, mainly the shortest diameter, due to the clip application, that leads to a reduction of the perimeter and the area of the annulus.