ARGUS “Assisting peRsonal GUidance System for people with visual impairment”

Oihana Otaegui – Vicomtech-IK4

List of Contents Argus Consortium

Motivation

Objectives

Argus System

Headphonests

Argus Preliminary Tests

Conclusions

ARGUS: Assisting personal guidance system for people with visual impairment

FP7-ICT-2011-7

Duration: 30 Months

Start date: 01.10.2011

End date: 30.03.2014

http://

www.projectargus.eu

Motivation

Visually disabled people have striking needs for trustful navigation systems providing them efficient mobility services, mainly considering safety and autonomy.

Limitations of existing products and solutions:

• Lack accuracy and integrity: they do not provide a suitable and efficient man-machine interface adjusted to this user segment, or rely on costly infrastructures.

• Are based on GNSS providing information through graphical displays or verbal output.

• Are not convenient for people who cannot see or have to operate in environments where verbal instructions could interfere with other external sounds.

Motivation

People with visual impairment require

guidance support in outdoor activities.

Motivation and Goals

To develop a GNSS-based mobility service for people with impaired visually capabilities, to guide them along a pre-defined track, using acoustic and audio-haptic signals, which meets the level of accuracy and reliability they need in urban environment for improving their day-to-day life autonomy

ARGUS Guidance Concept

• The sequence of the bell rings allows any person to build a mental map of the path.

• Although the sound is the same it is perceived in a different way depending on the distance and orientation

• ARGUS PROPOSES 3D SOUND FOR GUIDANCE USING STEREO OUTPUT

Binaural audio

Binaural technologies reproduce the interaural differences (arrival time and amplitude between the ears).

Binaural sounds create the illusion that sounds produced by a stereo headphone emanate from specific directions and distances in the surrounding space.

System Operation

GPX file is loaded in the user terminal and activated for track guidance to reproduce the path and reach the destination.

GPX file is loaded in the user terminal and activated for track guidance to reproduce the path and reach the destination.

A. Track Recording

B. Track on Map Processing

C. Track Server

Obtaining Track DataObtaining Track Data

Track RecreationTrack Recreation

GPX data (Tracks and Waypoints) can be obtained through different options

GPX data (Tracks and Waypoints) can be obtained through different options

Absolute System Reference

User System Reference

GPX data recorded and activated

Guidance instructions are provided based on user position and orientation obtained through GNSS and electronic compass

Guidance instructions are provided based on user position and orientation obtained through GNSS and electronic compass

Optional Head Mounted

System Architecture

Headphone setMain Objective: The selection and validation of headphones that meet the safety needs of the blind and partially sighted in outdoor navigation tasks. And specifically, headphones non-disturbing the general hearing of ambient sounds.

• Headphones non-disturbing the general hearing

1. Audiobone 2. Vibe BS NVE

• Normal headphones:

• 3. Elecom 4. Sennheiser

Wizard of Oz• Tool to carry out tests on binaural sounds perception and guiding

• Very valuable for user training and to help to define the values of the most relevant parameters of the Binaural Module of the PPoC

• Functionality– Set of applications for testing and training users.

– Oral STOP message to avoid risky situations

• Objective– Get the personalization options for the future ARGUS system

• Sound latency

• Orientation perception

• Distance between consecutive binaural points.

• Velocity between points

• Height of the perceived sound

– Trainning

User Tests

• Open field– Public meadow near the Airfield Paderborn-Haxterberg

– PPoC user tests

Test Results

• GNSS Reception Environment– Lower number of used satellites

– No jumping

• Good GNSS position performance

– User walked at higher speed 3-4 km/h

• COG and SOG smoother

• User Graphical Route– maximum deviation distance by the

external GPS was 3.23 meters

– maximum distance from the reference track during the first section was less than one meter

Test Results• GNSS Reception Environment

– 10 satellites on average: min7 max 11

– a static period of the user of about 30 seconds

– At the last third of the track, the user reduced his walking speed, when he approached the end point

• User Graphical Route– Except the third section, the other are inside

the -/+ 3 meters corridor during most of the time

– Section 2 - 3 very sharp angle. Not very common in real life. User must make an orientation change of more than 120º degrees to the left. The first instruction given by the audio at the reference point is a 90º change to the left (it is maximum value). Audio keeps asking for more orientation change, which may be perceived by the user as the first instruction being repeated

Graphical comparison of heading reaction vs. heading instructions

• From tests a KML file has been generated from the internal logs of the audio played during the tests and the individual compass heading measurements– Impossible to plot all the information, only

relevant point selected

– Powerful overview of the performance of the system and how the user reacts to each order

• Result– a good “order following”

– user reacts correctly to the orders

– The user process correctly the direction of the sound and therefore the user has no problem following the track

Graphical comparison of heading reaction vs. heading instructions

• Zoom view in 2nd user test where a late reaction of the user can be appreciated.– The arrows above the white line show

the direction of the played sound to guide the user

– the user takes a long time to change his walking direction.

– Although the system is trying to get the user back to the ideal track the user keeps deviating due to his late reaction

– To avoid this cases ARGUS system should increase the sound rate to warn the user and to encourage him to change his walking direction

Conclusions

• The results of the Preliminary Proof of Concept tests in Paderborn have been compiled in order to show the first tangible development of the ARGUS concept.

• Preliminary Proof of Concept of the guidance support system, using map/tracks, binaural sounds and satellite signals has been tested successfully with four end-users performing nine navigation tasks

• Although the users were aware that this was a preliminary prototype they were satisfied with ARGUS system guiding capability, simplicity and non disturbance of the general hearing

– the binaural guiding principle should be explained in detail before using the system in real navigation tasks in order to achieve optimum results

• The examined test parameters led to satisfying results with regard to the early stage of the current development phase

• The interviews highlighted the need of providing personalization options for the binaural guiding at the final prototype to cope with the high variability of technical skills and visual capabilities of the end users

• 7 out of 9 tests have an average distance error of below 5 meters to the ideal track in the four waypoint sections of the proposed route

Conclusions