design issues and empirical study in mobility oriented service developmentﰀ

Design Issues and Empirical Study in Mobility Oriented Service Development�

Tetsuo Yamabe

Distributed Computing Laboratory Waseda University

Preamble

¡  “How we should design mobile/wearable service interaction, in order to improve its mobility for nomadic people?” ¡  This work aims to explore the service design principles, with developing practical services.

¡  We are exploring approaches to decrease a user’s cognitive load (i.e. attention to a mobile service).

¡  This work was initiated in Nokia Research Center Tokyo.

Mobile Middleware: Embracing the Personal Communication Device (MobMid'08) , December 2, 2008, Leuven, Belgium

Outline

¡  Introduction & Motivation

¡ Design issues in mobile interaction & Our approach

¡ Prototyping & Experimental evaluation

¡ Discussion from findings and comments

¡  Future works

¡ Conclusion


!!Nowadays people are too addicted to mobile services. !! Using mobile phones while walking, on a bicycle, even driving a car…

!!Current mobile service design is too attention-consuming. !! From cognitive psychology point of view, “attention” is a key factor to improve mobile usability in the wild.

Introduction


Usability degradation on the move

!!Usability of mobile service becomes degraded while moving. !! Environmental transition - Situational disabilities forces a user to pay more attention.

!! Multitasking environment - Fragmentation of attention doesn’t allow a user to concentrate on mobile interaction.

!! Fine usability allows a user to perform tasks with less attention. !! Flexible and multimodal interaction is required.


Design issues in mobile interaction

¡  Multimodality ¡  Cognitive resource is limited, so mobile services should support multimodal interaction to approach available sense.

¡  Also wearable devices play important role to change the modality/presentation of feedback according to the level of its importance.

¡  Simplicity ¡  Direct feedback (stimulus) makes interaction style passive, so that a user doesn’t have to interact with a mobile service proactively (i.e. event-driven interaction).

¡  However, the direct stimulus should be simple in order to decrease cognitive load.

¡  Adaptability ¡  System should change the modality of interaction, since available sense changes according to mobile context.

¡  Also combination of available device changes according to users.


Multi-layered, Multi-modal and Multi-presentation approach for mobile/wearable interaction


Pedestrian navigation on a mobile device



Simple format indication on a head-mounted display


Detailed map on a ordinary mobile phone

Direct feedback: symbolic presentation



LED/LCD indication on a wrist watch type device












Direct feedback: ambient presentation



Tactile indication on a belt type wearable device









Tactile indication on a belt type wearable device




A ticker tape style indication Audio based indication

LED indication on an ordinary mobile phone



Text

Empirical study on a pedestrian navigation

¡ A pedestrian navigation service on N800 Nokia internet tablet. ¡  Added some simplified user interfaces and route navigation feature to maemo-mapper.

¡  3 different presentation styles are supported: ¡  Simple text sentence ¡  Simple voice message ¡  Simple visual indication



¡  The event types in the prototype, which makes direct feedback as an indication to a user.


2. Identify event types

1. Determine a user’s location with a GPS receiver


3. Navigate the user according to detected event types

Preliminary experimentation

¡ As the first step, we mainly focused on the simplicity in this evaluation. ¡  How the simplified indication works and affects to a user’s behavior? ¡  Compared normal interaction mode and simple interaction mode.

¡  Field experiments are performed with using the prototype. ¡  5 participants from NRC Tokyo joined. ¡  Two tasks are given to each participant.


Tasks

¡  Task A: Participants are instructed to walk Route A only with the normal interaction mode. The normal interaction mode shows the user's current location and route to the destination. The user can reach the destination by following the route, but the shown area on the display is small enough so that the user can not remember the entire route.

¡  Task B: Participants are instructed to walk Route B with a combination of the simple interaction mode (i.e. blink indication) and the normal interaction mode. In this case, the simple interaction mode has to be mainly used and the normal interaction mode is used auxiliary when the user has lost his/her way. Users can switch modes by manually pushing a hardware key.



¡ Number of corners and total distance are almost same.

Examinee observation


¡  Two observers pursued the participant with video cameras to record a user’s behavior and surrounding environment.

Experimental results !! TT [sec]: Total time spent to reach the destination !! ST [sec]: Total time of stationary state (i.e. just standing without walking) !! LT [sec]: Total (loss) time spent for walking incorrect route !! LD [m]: Total (loss) distance of incorrect route walking !! SP [km/h]: Average walking speed !! GR [%]: Proportion of time that the participant watch the display to TT !! MT [sec]: Total time of the normal interaction mode


Some findings and discussions

¡ Users would expect the next event and attempt to know when it will occur. ¡  Time to next event helps to create mental model in a user’s mind and prepare for the event.

¡  Some events and indications seem to be unnecessary. ¡  The blinking pattern was comprehensible, but no indication seems to be needed while the user is walking on the right route.

¡  Since the user interface on the simple user interaction mode was not interesting, users started to look the scenery.


Future work #1: Multiple device deployment

!!Advanced version of the prototype with multiple wearable devices. !! HMD: Nikon UP300x !! Visual/Audio modality !! Head gesture with 3D accelerometer

!! Wrist watch: SunSpot based prototype !! Visual/Haptic modality !! Gesture with 3D accelerometer !! Environmental sensors

!! Mobile: iPhone/iPod touch (or maemo platform) !! Visual/Audio modality !! Gesture with 3D accelerometer

!! Support gesture/context based adaptation Mobile Middleware: Embracing the Personal Communication Device (MobMid'08) , December 2, 2008, Leuven, Belgium

Future work #2: System support development


¡ Develop a middleware for multi-device interaction ¡  Device (resource) management ¡  Adaptation policy management ¡  I/O management ¡  Context sensing ¡  Gesture input ¡  Simplified event notification

¡ Develop a framework for multi-layered interaction design ¡  Multimodality ¡  Simplicity ¡  Adaptability

Dev � Dev �

Dev �

sensor� display �

App � App �

I/O desc�

Event desc�

Resource mgmr�

Context pool�

Adaptation policy �

Event Dispatcher�

Conclusion

¡ We have pointed out design issues in mobile interaction design, in order to improve usability of mobile services on the move.

¡ A pedestrian navigation service was developed and we evaluated its feasibility through field experiments.

¡ We have successfully decreased a user’s cognitive load by adding a simple interaction mode. ¡  Also, we have proved that the service semantics was successfully kept even in the simple interaction mode.

¡ We will continue to develop the system based on the comments and discussions, in order to realize the complete a picture of the proposed design framework.


APPENDIX


design issues and empirical study in mobility oriented service developmentﰀ

Technology