scholarly journals Impact of a Vibrotactile Belt on Emotionally Challenging Everyday Situations of the Blind

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7384
Author(s):  
Charlotte Brandebusemeyer ◽  
Anna Ricarda Luther ◽  
Sabine U. König ◽  
Peter König ◽  
Silke M. Kärcher
Keyword(s):  
Emotional Impact ◽  
Vibrotactile Stimulation ◽  
Angular Rotation ◽  
Straight Line ◽  
Before And After ◽  
Fixed Reference ◽  
Behavioural Experiments ◽  
Triangle Completion ◽  
Subjective Discomfort ◽  
Magnetic North

Spatial orientation and navigation depend primarily on vision. Blind people lack this critical source of information. To facilitate wayfinding and to increase the feeling of safety for these people, the “feelSpace belt” was developed. The belt signals magnetic north as a fixed reference frame via vibrotactile stimulation. This study investigates the effect of the belt on typical orientation and navigation tasks and evaluates the emotional impact. Eleven blind subjects wore the belt daily for seven weeks. Before, during and after the study period, they filled in questionnaires to document their experiences. A small sub-group of the subjects took part in behavioural experiments before and after four weeks of training, i.e., a straight-line walking task to evaluate the belt’s effect on keeping a straight heading, an angular rotation task to examine effects on egocentric orientation, and a triangle completion navigation task to test the ability to take shortcuts. The belt reduced subjective discomfort and increased confidence during navigation. Additionally, the participants felt safer wearing the belt in various outdoor situations. Furthermore, the behavioural tasks point towards an intuitive comprehension of the belt. Altogether, the blind participants benefited from the vibrotactile belt as an assistive technology in challenging everyday situations.

scholarly journals Evaluating the concepts of weak and subcognitive integration - an experimental study using vibrotactile sensory augmentation for the blind

2020 ◽  
Author(s):  
Anna Ricarda Luther
Keyword(s):  
Cognitive Processing ◽  
Subjective Experience ◽  
Angular Rotation ◽  
Sensory Augmentation ◽  
Directional Information ◽  
Attentional Resources ◽  
Completion Task ◽  
Attentional Load ◽  
Straight Line ◽  
Triangle Completion

Navigating in foreign surroundings necessitates peak concentration for blind travellers. Yet, most navigational aids heavily rely on attentional resources as well as on audition. Audition is a modality of supreme importance for the blind, allowing to react to cues of the immediate environment. Thus, it would be highly beneficial for a navigational aid for the blind to not or only partially rely on attentional resources and be easily interpreted and integrated into behaviour. Following the sensorimotor contingency (SMC) theory, which is embedded in the theoretical framework of embodiment, such endeavour has the potential to succeed by employing sensory augmentation devices. According to SMC theory, statistic regularities termed sensorimotor contingencies coupling action and perception are constitutive of conscious perception. Consequentially, since those regularities differ in between modality, also the qualitative experience of different modalities differ. Following this line of thought, new SMCs can be created through sensory augmentation devices and learned by exploring the SMC. The objective of this study is to further investigate if and to what extent such sensory augmentation device can be integrated into behaviour. Therefore, the weak integration hypothesis and the sub-cognitive processing hypothesis as established by Nagel et al. (2005) will be employed to evaluate the integration according to their criteria.Eleven congenitally and adventitiously blind adult subjects were provided with vibrotactile directional information of the magnetic north around the waist through a device termed naviBelt for seven weeks. At the beginning and at the middle of the study the integration of the signal of five participants was assessed using a battery of behavioural tests. These tests consisted of a straight-line-walking task, an angular rotation task and a triangle completion task. Furthermore, throughout the period of study all participants completed preliminary, weekly and final questionnaires, inspired by Kärcher et al. (2012). The questionnaires allowed to gain a more holistic picture of the subjective experience and the self-assessed benefits of the belt. In addition, two deaf-blind participants were provided with the belt for three to four weeks and answered questionnaires adjusted to their needs.The straight-line-walking task showed instant improvements in path stabilization when provided with the belt. In two participants characteristic behaviour of the sub-cognitive processing hypothesis is obtained. An overall improvement independent of whether the belt is worn or not is especially evident after the training period in the angular rotation task. This indicates an enhanced direction estimation accuracy, which is highly related to the understanding of the belt signal. Evidence for enhanced path integration and navigational skills through the belt can be found in the results of the triangle completion task. For two participants the performance improved even with an additional attentional load, hinting towards sub-cognitive processing.Overall, the data supports the weak integration hypothesis and points towards the sub-cognitive processing hypothesis and thus show that SMCs can be learned, which is in line with the theory of embodiment. Crucially, the study further exemplifies how such integration into behaviour can be of great benefit as assistive device for blind and deaf-blind.

scholarly journals The impact of the sensory augmentation device "feelSpace belt" on spatial orientation and navigation of blind people

2020 ◽  
Author(s):  
Charlotte Brandebusemeyer
Keyword(s):  
Spatial Orientation ◽  
Cognitive Skills ◽  
Blind People ◽  
Subjective Experiences ◽  
Vibrotactile Stimulation ◽  
Angular Rotation ◽  
Congenitally Blind ◽  
Allocentric Reference Frame ◽  
Behavioural Experiments ◽  
The Impact

Spatial orientation and navigation require cognitive skills, but most of all depend primarily on vision. Blind, visually impaired and deaf-blind people do not have this fast source of information about their environment available. To facilitate and enhance orientation and navigation and to make travelling outdoors safer for people deprived of visual input, the “feelSpace belt” can be used. The belt gives its wearer information about the magnetic north via vibrotactile stimulation around the waist. The aim of this study is to investigate to what extent the belt has an impact on the orientation and navigation abilities of blind people. Congenitally blind and late-blind subjects wore the belt for seven weeks in everyday situations and five of them additionally took part in behavioural experiments. Two deaf blind subjects wore the belt for three to four weeks. The experimental tasks took place before and in the middle of the participants’ training period. They consisted of a straight-line walking task to evaluate the belt’s effect on blind people trying to keep to the direction in which they are heading, an angular rotation task to examine the development of the egocentric orientation capabilities of the participants and a triangle completion navigation task to test whether the belt helps to take shortcuts. Weekly questionnaires gave an insight into the subjective experiences and evaluations of the participants. Overall, the belt’s information on cardinal directions proved to have intuitively a positive effect on the participants, facilitating especially orientation but also navigation. The results suggest that egocentric route based navigation, which has been shown in previous studies to be the favoured navigation strategy of blind people, was still preferred when the participants wore the belt but, due to the belt, was further extended by increased use of also the allocentric reference frame.

Automatic Tread Gaging Machine

1979 ◽  
Vol 7 (1) ◽  
pp. 31-39
Author(s):  
G. S. Ludwig ◽  
F. C. Brenner
Keyword(s):  
Experimental Tests ◽  
Automatic Machine ◽  
Wear Rates ◽  
Handling Device ◽  
Straight Line ◽  
Component Systems ◽  
Before And After ◽  
Good Repeatability ◽  
The Difference ◽  
Straight Lines

Abstract An automatic tread gaging machine has been developed. It consists of three component systems: (1) a laser gaging head, (2) a tire handling device, and (3) a computer that controls the movement of the tire handling machine, processes the data, and computes the least-squares straight line from which a wear rate may be estimated. Experimental tests show that the machine has good repeatability. In comparisons with measurements obtained by a hand gage, the automatic machine gives smaller average groove depths. The difference before and after a period of wear for both methods of measurement are the same. Wear rates estimated from the slopes of straight lines fitted to both sets of data are not significantly different.

Perceptual Learning Is Specific to the Trained Structure of Information

2013 ◽  
Vol 25 (12) ◽  
pp. 2047-2060 ◽  
Author(s):  
Yamit Cohen ◽  
Luba Daikhin ◽  
Merav Ahissar
Keyword(s):  
Temporal Structure ◽  
Frequency Discrimination ◽  
Perceptual Task ◽  
Hierarchy Theory ◽  
Tone Frequency ◽  
Potential Cost ◽  
Before And After ◽  
Group A ◽  
Fixed Reference ◽  
Key Questions

What do we learn when we practice a simple perceptual task? Many studies have suggested that we learn to refine or better select the sensory representations of the task-relevant dimension. Here we show that learning is specific to the trained structural regularities. Specifically, when this structure is modified after training with a fixed temporal structure, performance regresses to pretraining levels, even when the trained stimuli and task are retained. This specificity raises key questions as to the importance of low-level sensory modifications in the learning process. We trained two groups of participants on a two-tone frequency discrimination task for several days. In one group, a fixed reference tone was consistently presented in the first interval (the second tone was higher or lower), and in the other group the same reference tone was consistently presented in the second interval. When following training, these temporal protocols were switched between groups, performance of both groups regressed to pretraining levels, and further training was needed to attain postlearning performance. ERP measures, taken before and after training, indicated that participants implicitly learned the temporal regularity of the protocol and formed an attentional template that matched the trained structure of information. These results are consistent with Reverse Hierarchy Theory, which posits that even the learning of simple perceptual tasks progresses in a top–down manner, hence can benefit from temporal regularities at the trial level, albeit at the potential cost that learning may be specific to these regularities.

Dynamic Modeling and Analysis of a Two D.O.F. Mobile Manipulator

2000 ◽  
Author(s):  
D. Naderi ◽  
A. Meghdari ◽  
M. Durali
Keyword(s):  
Dynamic Modeling ◽  
Degrees Of Freedom ◽  
Ground Surface ◽  
Mobile Manipulator ◽  
Two Degrees Of Freedom ◽  
Modeling And Analysis ◽  
Straight Line ◽  
Fixed Reference ◽  
Line Trajectory ◽  
Straight Line Trajectory

Abstract This paper presents the kinematic and dynamic modeling of a two degrees of freedom manipulator attached to a vehicle with a two degrees of freedom suspension system. The vehicle is considered to move with a constant linear speed over an irregular ground-surface while the end-effector tracks a desired trajectory in a fixed reference frame. In addition, the effects of highly coupled dynamic interaction between the manipulator and vehicle (including the suspension system’s effects) have been studied. Finally, simulation results for the end-effector’s straight-line trajectory are presented to illustrate these effects.

The Discrimination of Dynamic Orientation Changes in Gratings

Perception ◽  
1995 ◽  
Vol 24 (6) ◽  
pp. 665-679 ◽  
Author(s):  
Michael J Wright ◽  
Kevin N Gurney
Keyword(s):  
Spatial Frequency ◽  
Visual Memory ◽  
Frequency Function ◽  
Short Isis ◽  
Angular Rotation ◽  
Spatial Frequencies ◽  
Straight Line ◽  
Order Of Magnitude ◽  
Data Points ◽  
Best Fitting

Thresholds were measured for discrimination of direction of a step angular rotation of gratings. The addition of simultaneous phase displacements (translation) had little effect on rotation thresholds for gratings over a considerable range; discrimination of rotation is unaffected by random directional translations an order of magnitude larger. Angular rotation discrimination thresholds increased with interstimulus interval (ISI). Thus discrimination is based at short ISIs (180 ms or less) on a percept of rotary motion, but at ISIs of several seconds by a spatial strategy (comparing static component orientations) relying on visual memory. Data points for the short-ISI region fell below the best-fitting straight line, and the slope of the short-ISI region of the curve was steeper than that of the long-ISI region. However, when either compound or simple gratings with uncorrelated spatial frequencies were used in the two stimulus frames, there was no evidence for a separate function at short ISIs. Orientation-change thresholds were measured for simple gratings as a function of contrast and spatial frequency. The contrast function showed saturation and the spatial frequency function was U-shaped. Rotation sensitivity for gratings is thus similar in its spatiotemporal properties to translation sensitivity. The findings support the proposal that rotation discrimination (at short ISIs) is achieved by a template mechanism combining signals from different directional detectors, rather than by cognitive comparison of the outputs of the directional mechanisms themselves.

Evaluation of Glove Liners with Objective, Subjective and Performance Measures

1998 ◽  
Vol 42 (12) ◽  
pp. 846-850 ◽  
Author(s):  
S. C. Chen ◽  
I. Tarawneh ◽  
B. Goodwin ◽  
R. R. Bishu
Keyword(s):  
Performance Measures ◽  
Health Care Providers ◽  
Performance Tests ◽  
Care Providers ◽  
Before And After ◽  
Two Temperatures ◽  
And Performance ◽  
Subjective Discomfort ◽  
Skin Moisture ◽  
Skin Sensitizer

The objective of this study was to evaluate a number of inner glove liners used to protect the skin from latex proteins and chemical skin sensitizer found in gloves. A battery of performance tests were used for evaluating the inner gloves. Besides these, objective measurements such as skin temperature, skin conductance, and skin moisture content were measured. A series of subjective discomfort/comfort measures were also taken. Seventeen health care providers participated in this experiment where four liner conditions were evaluated at two temperatures. Some of the measures were recorded before and after the tests, while some other measures were recorded every fifteen minutes. Thus each subject participated in eight trials (4 liners X 2 temperatures). The tests were of two hours duration. Sweat, pegboard test, and discomfort measures were the best discriminators of liners, while the other subjective and objective measures were not.

The effect of tracked vehicles on soil strength and micro-relief of a calcareous earth (Gc1.12) North of Woomera, South Australia.

1985 ◽  
Vol 7 (1) ◽  
pp. 17 ◽  
Author(s):  
MV Braunack
Keyword(s):  
South Australia ◽  
Soil Strength ◽  
Tracked Vehicle ◽  
Tracked Vehicles ◽  
Straight Line ◽  
Before And After ◽  
A Site

Changes in soil strength and surface micro-relief were measured in a calcareous earth (Gc. 1.12) at a site north of Woomera, before and after the passage of a tracked vehicle. The passage of a tracked vehicle resulted in a reduction of ?oil strength and the formation of ruts. The degree of change depended on the number of vehicle passes and whether the vehicle was travelling in a straight line or turning. Implications for erosion are discussed.

Dynamic Interaction Between the Manipulator and Vehicle of a Mobile Manipulator

1999 ◽  
Author(s):  
A. Meghdari ◽  
M. Durali ◽  
D. Naderi
Keyword(s):  
Degrees Of Freedom ◽  
Dynamic Interaction ◽  
Suspension System ◽  
Mobile Manipulator ◽  
Moving Vehicle ◽  
Straight Line ◽  
Fixed Reference ◽  
Line Trajectory ◽  
Time And Energy ◽  
Straight Line Trajectory

Abstract A manipulator mounted on a moving vehicle is called a mobile manipulator. A mobile manipulator with an appropriate suspension system can pass over uneven surfaces, thus having an infinite workspace. If the manipulator could operate while the vehicle is traveling, the efficiency concerning with the time and energy used for stopping and starting will be increased. This paper presents the kinematics and dynamic modeling of a one degree of freedom manipulator attached to a vehicle with a two degrees of freedom suspension system. The vehicle is considered to move with a constant linear speed over an uneven surface while the end effector tracks a desired trajectory in a fixed reference frame. In addition, the effects of dynamic interaction between the manipulator and vehicle (including the suspension system’s effects) have been studied. Simulation results from straight line trajectory are presented to illustrate these effects.

A new performance based design approach for moment resisting frames

2012 ◽  
Vol 39 (4) ◽  
pp. 473-483 ◽  
Author(s):  
Mark Grigorian ◽  
Carl E. Grigorian
Keyword(s):  
Design Method ◽  
Seismic Loading ◽  
Performance Based Design ◽  
Equilibrium Conditions ◽  
Future Behavior ◽  
Straight Line ◽  
Before And After ◽  
Moment Resisting ◽  
Strength And Stiffness ◽  
Constituent Elements

This paper proposes a simple, relatively new elastic–plastic design method for earthquake resisting frames that enables the engineer to directly control the essential aspects of the future behavior of certain structural forms, through basic statics and imposition of predetermined modes of behavior. The method is particularly applicable to the preliminary design of low to mid-rise buildings where the fundamental period of vibrations dominates the response of the system to seismic loading. The focus of this paper is directed towards simplified but accurate manual design rather than sophisticated structural analysis. The premise of the proposed solution is that the constituent elements of the system can be selected in such a way as to cause both the elastic as well as the plastic drift functions to follow linearly varying straight line profiles during all phases of loading. Frameworks designed by this method act not only as structures of uniform response (UR), i.e., uniform strength and stiffness, where the demand/capacity ratios of its members remain the same, both before and after formation of plastic hinges, but they also result in unique solutions, satisfying the prescribed yield criteria, the boundary support, as well as the of static equilibrium conditions.

Sign in / Sign up

Export Citation Format

Share Document