In this paper we investigate how we can change interactions with mobile devices so we can better support subtle low effort intermittent interaction. In particular we conducted an evaluation with varying interaction techniques which looked at non-visual touch based exploration of information on a capacitive surface. The results of this evaluation indicate that there is very little difference in terms of selection accuracy between the interaction techniques that we implemented and a slight but significant time reduction when using multiple fingers to search, over one finger. Users found locating information and relating information to physical landmarks easier than relating virtual locations to each other. In addition it was found that search strategy and interaction varied between tasks and also at different points in the task.

This paper presents a study that explores the issues of mobile multimodal interactions while on the move in the real world. Because multimodal interfaces allow new kinds of eyes and hands free interactions, usability issues while moving through different public spaces becomes an important issue in user experience and acceptance of multimodal interaction. This study focuses on these issues by deploying an RSS reader that participants used during their daily commute every day for one week. The system allows users on the move to access news feeds eyes free through head- phones playing audio and speech and hands free through wearable sensors attached to the wrists. The results showed participants were able to interact with the system on the move and became more comfortable performing these interactions as the study progressed. Users were also far more comfortable gesturing on the street than on public transport, which was reflected in the number of interactions and the perceived social acceptability of the gestures in different contexts.

This paper presents a study looking into the effects of walking and the use of visual and audio feedback on the application of pressure for linear targeting. Positional and Rate-based control methods are compared in order to determine which allows for more stable and accurate selections, both while sitting and mobile. Results suggest that Rate-based control is superior for both mobile (walking) and static (sitting) linear targeting, and that mobility significantly increases errors, selection time and subjective workload. The use of only audio feedback significantly increased errors and task time for Positional control and static Rate-based control, but not mobile Rate-based control. Despite this, the results still suggest that audio control of pressure interaction while walking is highly accurate and usable.

We present McSig, a multimodal system for teaching blind children cursive handwriting so that they can create a personal signature. For blind people handwriting is very difficult to learn as it is a near-zero feedback activity that is needed only occasionally, yet in important situations; for example, to make an attractive and repeatable signature for legal contracts. McSig aids the teaching of signatures by translating digital ink from the teacher's stylus gestures into three non-visual forms: (1) audio pan and pitch represents the x and y movement of the stylus; (2) kinaesthetic information is provided to the student through a force-feedback haptic pen that mimics the teacher's stylus movement; and (3) a physical tactile line on the writing sheet is created by the haptic pen. McSig has been developed over two major iterations of design, usability testing and evaluation. The final step of the first iteration was a short evaluation with eight visually impaired children. The results suggested that McSig had the highest potential benefit for congenitally and totally blind children and also indicated some areas where McSig could be enhanced. The second prototype incorporated significant modifications to the system, improving the audio, tactile and force-feedback. We then ran a detailed, longitudinal evaluation over 14 weeks with three of the congenitally blind children to assess McSig's effectiveness in teaching the creation of signatures. Results demonstrated the effectiveness of McSig—they all made considerable progress in learning to create a recognizable signature. By the end of ten lessons, two of the children could form a complete, repeatable signature unaided, the third could do so with a little verbal prompting. Furthermore, during this project, we have learnt valuable lessons about providing consistent feedback between different communications channels (by manual interactions, haptic device, pen correction) that will be of interest to others developing multimodal systems.

When designing interfaces for mobile devices it is import-ant to take into account the variety of contexts of use. We present a study that examines how changing noise and dis-turbance in the environment affects user performance in a touchscreen typing task with the interface being presented through visual only, visual and tactile, or visual and audio feedback. The aim of the study is to show at what exact environmental levels audio or tactile feedback become inef-fective. The results show significant decreases in perform-ance for audio feedback at levels of 94dB and above as well as decreases in performance for tactile feedback at vibration levels of 9.18g/s. These results suggest that at these levels, feedback should be presented by a different modality. These findings will allow designers to take advantage of sensor enabled mobile devices to adapt the provided feed-back to the user's current context.

Developing interfaces for mobile situations requires that devices are useable on the move. Here, we explore head tilting as an input technique to allow a user to interact with a mobile device 'hands free'. A Fitts' Law style evaluation is described where a user acquires targets, moving the cursor by head tilt. We explore d position and velocity control cursor mechanisms in both static and mobile situations to see which provided the best level of performance. Results show that participants could successfully acquire targets using head tilting. Position control was shown to be si gnificantly faster and more accurate in a static context, but exhi bited significantly poorer accuracy and longer target acquisition times when the user was on the move. We further demonstrate how analysis of user's gait shows consistent targeting biases at different stages in the gait cycle.

"McSig" is a multimodal teaching and learning environ-ment for visually-impaired students to learn character shapes, handwriting and signatures collaboratively with their teachers. It combines haptic and audio output to realize the teacher's pen input in parallel non-visual modalities. McSig is intended for teaching visually-impaired children how to handwrite characters (and from that signatures), something that is very difficult without visual feedback. We conducted an evaluation with eight visually-impaired children with a pretest to assess their current skills with a set of character shapes, a training phase using McSig and then a post-test of the same character shapes to see if there were any improvements. The children could all use McSig and we saw significant improvements in the character shapes drawn, particularly by the completely blind children (many of whom could draw almost none of the characters before the test). In particular, the blind participants all expressed enjoyment and excitement about the system and using a computer to learn to handwrite.

In this paper, we investigate wrist rotation as a hands-free method of interaction with a mobile device. To evaluate this technique, a Fitts' Law targeting study is described in four different postures: resting, seated, standing and walking. Results show correlations in movement time and the Index of Difficulty of the task and similarities in the targeting performance for the first three conditions, but show walking and targeting using this method was significantly more difficult.

This work introduces the idea of haptic rendering using granular synthesis - an established technique for synthesising audio. It describes the technique along with potential application areas, and initial results from an implementation on a PHANToM force feedback device. Three main applications are considered. Firstly, rendering of probabilistic vector fields for presenting ambiguity and context information to the user. Secondly, the possibility of producing textured virtual objects using granular synthesis is discussed. Thirdly, we use the approach to display scatterplot data on haptic devices.