Bendswipe
A study on interactive gestures on future foldable devices
Background
Our research focused primarily on one-handed interaction of users with their handheld devices.
During our study, we came across various pitfalls in one-handed interactions of mobile handheld devices such as poor reachability, re-gripping, occlusion and reduced accuracy that leads to poor user experiences.
So we aimed to design efficient input interaction in flexible handheld devices as it offered opportunities of deformation that may result in effective one-handed user interactions, especially for tasks that require multi-finger and/or multi-step interactions like target zooming of any display content.
One handed usage of handheld devices is commonly observed in situational impairments, e.g. walking, sitting and standing where the other hand is busy doing real-world tasks. Therefore, design of suitable input interactions for one-handed usage becomes necessary in common scenarios of situational impairment.
Contribution
User Research, Interaction Design, Prototype development, User Evaluation
Methodology
Human-centred design methodology
Team
2 Research Associates
Project
Sponsored by Nokia
Process
User Research
Desk Research
User Interviews
Synthesis
Ideation
Interactive gestures
Prototyping
Prototype development
Arduino Programming
Iteration
User Testing
Product improvements
Proposed Gestures
To enable easy target zooming of any display content, we chose a combination of bend gesture and touch supported swipe gesture on backside of flexible handheld device.
Zoom-in and out is triggered by performing a bend and swipe gesture simultaneously.
A zoom-in to a display content is done by-
Performing a center squeeze which bends the central vertical axis (Fig. 1) towards the user
Performing a linear swipe gesture in any direction on the back of the device that triggers the zoom-in in the exact direction of the swipe gesture
A zoom-out to a display content is done by-
Performing a center squeeze which bends the central vertical axis (Fig. 2) away from the user
Performing a linear swipe gesture in any direction on the back of the device that triggers the zoom-out in the exact direction of the swipe gesture
Prototype Development
The flexible prototype is made out of a thin sheet of paper (5.5 size) laminated with plastic sheets on both sides. The plastic coating gives the device the ability to bend and twist easily along with elasticity
A bend sensor is located diagonally (on the backside) to detect bend-in and bend-out of the flexible device (Fig. 3). To detect and track the finger swipe gesture at the back of the device, a deformable and conductive sensor material is used that is placed on the backside of flexible device. The bend sensor and the conductive sensor material sends the data to the Arduino microcontroller to control
User Evaluation
We presented an input method to zoom-in or out towards location specified in above figure in a continuous and controlled manner.
A total of 20 participants (university students) were chosen for the user testing.
To evaluate the effectiveness of this interaction technique, we conducted within subject comparative evaluation between rigid handheld device (Smartphone Moto G2) and proposed flexible handheld device in two positions (performing target zooming in sitting situation and standing situation)
Through this evaluation, we explored the capabilities of deformation gestures to augment touch gestures in order to extend their functionality for one-handed handheld usage.
The comparative study investigated variables (a) task completion time to zoom to several specific target areas and (b) number of re-gripping events while performing the target zooming during the task. Paired sample t-test was used to evaluate task completion time, re-gripping effect and all usability variables in our experiment.
Evaluation Results
Task Completion– In sitting scenario, our results show that time taken to zoom-in all locations (1-8) was significantly less (p<0.05 for all target zooming location) on flexible device, whereas in standing scenario time taken to zoom-in all locations apart from bottom right corner location (8th location) was significantly less (p<0.05). Task completion time to zoom-out for bottom right corner location (8th location) was significantly less(8-p<0.05) on flexible device in both sitting and standing scenario, although for all other locations the time taken to zoom-out was non significant (p>0.05).
Total Re-gripping Events– Our results show that the number of re-gripping events is significantly less on flexible device in both sitting (p<0.05) and standing scenario (p<0.05). The total number of re-gripping events on flexible device in sitting position is less than in standing position but the difference is not significant (p>0.05).
From this project, I learned that the morphology of our hands are such that the index finger can easily perform touch gestures on the back side of devices while maintaining grip on the phone with other fingers.
© 2024 Mayank Chhabra