Supporting Navigation with a Torso Wearable Tactile Display

November 1st, 2018

Categories: Devices, Human Factors, MS / PhD Thesis, Software, User Groups, Human Augmentics, Augmented Reality, Mixed Reality, Instrumentation

Positioning of Sensor Modules and Controller Box
Positioning of Sensor Modules and Controller Box


V. Mateevitsi


Umwelt, the German word for environment, is a psychology term referring to the individual’s mental image of the surrounding world. This subjective universe is shaped by an organism’s unique perception of the environment around them and, therefore, differs from individual to individual. In other words, organisms experience the world through their senses, construct the mental model of their vicinity, and react upon it. Hence, this image never remains static - instead it is constantly refined, as a result of the dynamic nature of the world. Umwelt is closely related to the concept of Situation Awareness, that is the perception of environmental elements, comprehension of their nature, and projection of their near future status with respect to time and/or space.

Sensory perception (exteroception) of the surrounding environment is, as a matter of fact, restricted to the limitations of biological senses. For example, although we consider humans with five fully developed senses (sight, hearing, touch, smell and taste) as able-bodied individuals, they are essentially blind to a multitude of information that constantly surrounds them. To put things into perspective, both human sight and hearing, can only perceive a fraction of information- part of the electromagnetic spectrum (light waves), and of the sound frequencies accordingly. However, as sensory systems differ among species, other creatures have an entirely different perceptual experience, as they are able to perceive a distinct spectrum of information.

Despite the fact that our limited human senses restrict our Umwelt and, therefore, our Situation Awareness, Human Augmentics, referring to technologies that expand the capabilities and characteristics of humans, allows us to peek into an invisible &dlquo;other&drquo; world. Thus, some important questions arise: What would the consequences of an expanded perception of the surrounding environment be, and how would that affect an individual’s Situation Awareness? Since our Umwelt is limited by genetics, how would individuals attune with characteristics and capacities that lie beyond human range? Could Human Augmentics possibly expand an individual’s Umwelt, leading to improved Situation Awareness?

Jakob von Uexkull (1864 - 1944), a German biologist who worked on animal behavior studies, cybernetics of life, and muscular physiology, is attributed for coining the term Umwelt. Uexkull’s Umwelt is the phenomenal world of a living animal, in which it exists and acts, and as a result is shaped according to the stimuli received from its senses. Due to the fact that individuals, even across the same species, sense the world differently, each animal creates its own unique Umwelt.

Perception and, as a result, interaction with the world begins with the raw input of data from the environment through the sensory system. Anatomically, the sensory system is part of the nervous system and includes the sensory receptors that act as probes of the environment, parts of the brain that are used for sensory perception, and the neural pathways that connect the brain with the receptors. Notably, humans’ sensory system consists of five traditional senses: Sight, hearing, taste, smell and touch. The stimulation type and bandwidth of each sensory channel are limited to its characteristics, which in turn constrain the size of the Umwelt. However not all living organisms possess the same qualitative or quantitative senses. Depending on the environment in which they have evolved, their sensory system may be entirely different than ours; some have more while others have less sensitive senses. Others have quite different ones. Bats and dolphins, for instance, have the ability to calculate orientation and position of other animals and objects through reflected beams of sound, an ability known as echolocation. Sharks and rays, on the other hand, can detect changes in the electric field of their vicinity, an ability known as electroreception.

Situation Awareness
It is a well-known fact that humans are capable of sensing only a small fraction of the data that constantly surrounds us. Magnetic fields, infrared light, ultrasound, cosmic rays, radiation are just a few of the things that are completely invisible to us. However, recent technological advances in specialized sensors, enable the detection of some of this information. For instance, geiger counters are used by hazmat personnel to assess radiation levels in nuclear accidents. These technologies provide feedback using one of our existing senses, usually visual or audio, in order to help workers safely perform daily tasks.

Situation Awareness (SA) is the perception of environmental elements, comprehension of their nature, and projection of their near future status with respect to time and/or space. In other words, it is the awareness of the immediate vicinity, comprehension of the current state of the environment and ability to predict what may happen. Inputs from the sensory system are used by the individual in order to create and update their Situation Awareness state, and as a result, decisions depend on the accuracy of the perceived model. Situation Awareness is tightly associated with experience; somebody less experienced may miss information that a more experienced user will not. To put things into perspective, the hazmat personnel’s (that we discussed above) Situation Awareness includes the geiger counter readings, comprehension of their meaning and ability to predict what will happen if they raise above a certain level.

Despite the fact that sensory systems have been honed by millions of years of evolution, they are very limited to a multitude of data. We are blind to a plethora of information that exists around us, and fortunately most of it is harmless. We depend on our sensory system to interpret the world, and we use our Situation Awareness to comprehend the environment around us and act upon it. As a result, lack of information for a certain situation may lead to misjudgements and accidents. In fact 76% of aviation errors, happen because the pilot did not perceive one piece of the airplane’s crucial information. To that end, another important question arises: Given that today’s technology can sense some of this invisible information, can we expand the Umwelt and improve Situation Awareness?

Research Questions
Genetic defects, diseases or accidents can lead to sense disabilities or complete sense lose, which has been observed to both animals and humans. To that end, individuals learn over time to use the remaining of their senses in order to overcome a disability. Recent scientific discoveries have shown that while this new ability results in anatomical changes of the brain, the responsible regions remain the same. In other words, even though the sensory input channel has changed, the brain will still process the information in the same region|a phenomenon known as Sensory Substitution.

As a result, Sensory Substitution devices use one or more of the remaining senses to increase an individual’s Situation Awareness through a different sensory pathway. More specifically, tactile displays are able to translate external environmental information onto one’s skin, through the use of haptics. While these systems are primarily designed for people with disabilities, their concepts can be extended to other sensory deprived individuals, who find themselves in no or limited visibility environments due to external, environmental reasons. For example, firefighters operating within smoky, low visibility hazardous environments or soldiers fighting in pitch black darkness, are more likely to have no Situation Awareness of their surrounding environment.

The ever-dynamic nature of the world around us, however, makes navigating with a wearable tactile display, a quite challenging task. From feeling the vibrations onto one’s skin, comprehending their meaning and correctly acting upon them, to getting inundated with tactile sensory overload, tactile displays have great potential, when communicating information in an eloquent way.

In this dissertation we will explore different environment-to-vibration mappings while assessing one’s Situation Awareness. Furthermore, we seek to understand whether one's experience with a tactile display would have an effect on their Situation Awareness. Finally, we hypothesize that a one-size-fits-all wearable tactile display would not perform equally well in all environmental scenarios and therefore we are going to explore how different vibration configurations, patterns and environment-to-vibration mappings would affect one’s navigation. All of the above are distilled into the following research questions:

- Could tactile displays be used to increase Situation Awareness of visually deprived individuals?

- To what extent would Situation Awareness be associated with experience when using a tactile display?




V. Mateevitsi, Supporting Navigation with a Torso Wearable Tactile Display, Submitted in partial fufillment of the requirements for the degree of Doctor of Philosophy in Computer Science, Graduate College of the University of Illinois at Chicago, November 1st, 2018.