Architecting an Intercommunicative Experimental Environment

with Research Participants and its Parameters

Proceedings of the 2012 Japan-Taiwan Symposium on intelligent Green and Orange (iGO) Technology,held on December 10 – 11, 2012 at National United University, MiaoLi, Taiwan

Sendai National College of Technology

Nakai Akihito , Yairi Satoshi1

Orientation & Mobility

• The blind must be able to perceive their circumstances

with their

ears.

• This skill is known as “Auditory Orientation”

• The visually impaired can work with specialists of

Orientation & Mobility to receive training in auditory

orientation, with the aim of

being able to function in daily life.

2

Orientation & Mobility

• Training “auditory orientation” for the blind is usually conducted in the real world, however…

the real world is dangerous, especially for beginner trainee.

• Training conducted with auditory Virtual reality (VR) sound, known as auditory display provided with HRTFs would be helpful.

3

What is HRTF?

• This function can extract

“locational

information” (direction,

distance) of

sounds.

• HRTF can be combined with another

sound data.

• HRTF can convolute 3D perception of

the recorded HRTF point with sound

data.

• Head-Related Transfer Function (HRTF)

HRTF is usually measured.Problems: Long duration of

measurement,and other

obstacles when obtaining HRTF.

4

• In fact, there are several ways to obtain an HRTF other than

measurement.

• Assuming blind people, an HRTF was obtained from a database that

contains many precisely measured HRTFs.

Thus, we aim to measure HRTF as precisely as possible

in healthy individuals to produce a precise HRTF database.

Goal: a system which can be easily applied to

measurement HRTF,

with minimal stress to subjects.

HRTF for The Blind

5

• HRTF measurement takes at least 2 hours per person.

• Subjects must maintain their body position for the entire measurement period to

obtain a precise HRTF.→ This procedure requires tense

concentration, and is quite

tiring.

HRTF Measurement

6

• Sleepiness while measuring in anechoic chamber

Silent chamber and nothing to do.

• Unconscious motion of Head & Body

Hard to maintain exactly same body position.

We propose a system that can grasp the status

of subject being measured in the anechoic chamber

via sensor parameters.

Measurement Problems

7

• Using a Kinect to get positions of a subject’s body.

• Using iPod touch with a “gyrosc” app.

to obtain precise head

motion data.

• Using iPad with a “touchOSC” app.

to notify the subject’s body

motion.

Varying Position Notification

with Sensors

8

Varying Position Notification

with Sensors

9

• iPod gyro sensor can precisely measure accurate tilts. (iPod touch is used for reference

values)

・ iPad notifies the subject’s

motions via wireless LAN.

• Kinect can observe whole body motion

even in depth direction.

10

Overview of Proposed System

Measurement on This System

11

Set measurement mode

↓

Set initial body position

↓

Keep body position according to

notification

Set Measurement Mode

12

• Make a circle above

subject’s head 4 seconds after seating.

• Kinect will cease to capture leg motion,

and reference doll will be set

in a

seated position.

• Make a circle above the subject’s head

for 8

seconds to disable the mode.

Set Initial Body Position

• After mode setting, the subject

raises his right hand level with

his shoulder, and decides initial

body position.

• Without bending it, the subject

moves his right arm ahead.

This triggers position

calibration.

• Finally, the subject puts his

hands on his knees. 13

Keep Body Position According to Notification

14

Keep Body Position According to Notification

• Center coordinate shows the subject’s head

position.

• Estimating Head position with the head and torso coordinate values.

• When there are inclines, a

green point will light up.

15

Keep Body Position According to Notification

• With a 1 - 3 deg. incline, yellow points

will light up.

• Or with a 4 - 7 deg. incline, orange points will

light up.

• With inclines over 8 deg. ,red points will light

up.16

Conclusion

• An intercommunicative experimental environment

consisting of some devices and sensors is

proposed.

• Proposed prototype system can support precise

measurement HRTFs, and create on exact HRTF

database.

• Precisely measured HRTFs measured function

better perception of the blind in an auditory

orientation training system with the auditory

display. 17