Body-machine interfaces for non-homologous human-machine interactions

Virtual reality (VR), the interactive experience of being immersed in a simulated environment, has seen a tremendous development in the last years. Numerous applications came into being, ranging from flight simulators through a virtual ascent of Mount Everest, through surgery simulators or scenarios to treat acrophobia. These applications serve different purposes and are not designed for the same populations. To optimize the VR experience, these aspects must be taken into account during the development of virtual environments.

The intensity of a virtual experience depends on three main factors: the quality and rendering of the virtual environment, the interaction opportunities and aspects inherent to the user such as physical abilites or previous VR experiences.This thesis addresses the latter two aspects.

Part I describes the development of a body-machine interface for the immersive steering of simulated or real drones. Chapter 2 describes a systematic analysis of spontaneous gestural strategies selected by untrained participants asked to interact with a drone. I show the existence of patterns common to the considered population. In chapter 3, I use these patterns to define gestural control strategies to pilot a drone. In particular, I demonstrate that using a set of torso movements leads to better steering performances and faster learning than with a joystick commonly used for this kink of tasks.

In Part II, I focused on multisensory integration, which is necessary to interact with such a system, and the development thereof along childhood. In chapter 4, I evaluated the steering abilities of 6-10 year-old children on the flight simulator developed earlier. These experiments revealed that the selection of the appropriate head-trunk coordination strategy is immature in children until the age of 8, even if these strategies are already part of the postural repertoire. Eventually, in chapter 5, a virtual archery game highlighted the development of visuomotor integration during childhood.

These studies emphasized the benefits of user-driven interaction interfaces over pre-existing devices and brought up age-related interaction differences which should be considered when designing virtual environments.

A Framework for Measuring Urban Sprawl from Crowd-Sourced Data

Martí Bosch Padros

The amount of people living in cities by 1800 was roughly around 3 percent of the world population. This number has increased dramatically during the last centuries, and currently it is estimated that one out of two people lives in cities. Furthermore, according to United Nations 60 percent of the world population will live in cities by 2030. This situation brings new challanges on how to conceive cities that host such amounts of population in a sustainable way while sacrificing as little as possible the inhabitants’ quality of life. This sustainability should address to several aspects that can be classified as economical, social and environmental. The cities are and will be centers of economical activity, and thus should provide facilities for business, innovation and culture. Such economical development should benefit all the levels of the social hierarchy, preventing inequalities and social segregation. The environmental part concerns the efficient utilization of the resources as well as the minimization of the impact on the ecosystems that sourround such cities. A convenient public transportation network, the preservation of green areas, the recycling of waste or the use of renewable energies are some examples of means to reduce the cities’ environmental impact. Unluckily by taking a look at the current megacities, it can be easily observed that very few of them meet the sustainability characteristics formerly reviewed. This can be partly explained by the urbanism pattern that derives from the processes of industrialization. When a city experiences such industrialization, with the related economic growth and the expansion of transportation networks, the middle class tends to migrate towards the outskirts of the city, potentially to live in terraced houses sorrounded by green areas. Such a pattern is commonly referred to as urban sprawl, and it was first observed in London and Paris during the 19th century. Cities like New York, Chicago went through this process during the early 20th century, and so did most central and northern- European cities around 1970-1990. Nowadays urban sprawl might even be more prevalent in developing countries, as it is the case with Mexico City, Beijing, Delhi, Johannesburg or Cairo.

2016

Wearable Technologies for Embodied Human-Robot Interaction

Carine Rognon

Robotic teleoperation is fundamental to augment the resilience, precision, and force of robots with the cognition of the operator. However, current interfaces, such as joysticks and remote controllers, are often complicated to handle since they require cognitive effort and learned skills. Wearable interfaces can enable more natural and intuitive interactions with robots, which would make robotic teleoperation accessible to a larger population of users for demanding tasks, such as manipulation or search-and-rescue. The aim of this thesis is to explore solutions to simplify our interactions with robots promoting their access to a broader range of the population. To achieve this, we are presenting a soft upper body exoskeleton, called the FlyJacket, for the bidirectional control of drones. Drones can greatly benefit us as they extend our perception and range of action. The exoskeleton controls a drone by recording torso movement and, through embedded haptic feedback devices, renders either kinesthetic guidance to improve the flight performance or tactile feedback to render the sensation of flying. We developed and tested an interface to control both a simulated and a real drone. The FlyJacket is a soft exoskeleton with arm support conceived to address the challenges of adapting to different morphologies and supporting the user during flight to prevent fatigue. We demonstrated that this novel interface allowed more consistent performance than when performing the same task with a remote controller and users felt more immersed into the flight. Interacting with a robot can be greatly enhanced by having multiple channels of sensorial feedback to increase the awareness of the operator. Information on the state of the drone can be intuitively rendered with haptic feedback. To create this bidirectional interaction with the drone, the two types of haptic feedback - kinesthetic and tactile - have been explored. Kinesthetic feedback was implemented with a cable-driven system to give guidance to the userâs torso position. Performing user studies, we could determine that the embedded guidance improved the flight performance and that a quadratically shaped force feedback curve was the most adequate profile to guide the user. We also established the minimal force difference, defined the perceived magnitude of this system and studied the learning process of users. Tactile feedback was investigated to render the sensation of flying by enhancing flight awareness, realism and immersion. To this end, we developed and embedded a new type of soft actuator that was compliant and lightweight such that it remained wearable and portable. Four devices, placed on the torso, provided feedback by compressing closed air pouches against the skin rendering the sensation of air pressure. A mechanical model and simulation of the pouch device were developed to determine appropriate parameters. We evaluated whether it conveyed useful information to the user and whether it enhanced the experience of flying. We demonstrated that users were able to understand the direction of the cues without prompting, could distinguish the cues quickly, and do so with high accuracy. The device was also used in a simulated flight task and users indicated that it increased the flight realism. We believe that the contributions of this thesis provides insights to the design of intuitive interfaces for human-robot interaction and increases their accessibility to a wider range of the population.