Effects of touchscreen gesture's type and direction on finger-touch input performance and subjective ratings

Impact of swiping direction on the interaction performance of elderly-oriented smart home interface: EEG and eye-tracking evidence

Introduction

Smart home technology is increasingly popular, yet not all seniors are receptive and comfortable with it. This situation recognizes that the usability of smart home interfaces is particularly important. Most studies on interface swiping direction demonstrate the advantages of horizontal over vertical swiping, but the findings lack age-based as well as gender-specific judgments.

Methods

In this paper, we use cognitive neural techniques of EEG and eye-tracking, combined with a subjective preference questionnaire, to analyze the preference of older persons for the swiping direction of smart home interfaces in a multimodal manner.

Results

The EEG data showed that swiping direction had a significant effect on potential values (p = 0.001). Also, the mean power in the δ and the θ band was enhanced during vertical swiping. Gender had no significant effect on potential values (p = 0.085), but the cognitive task was more EEG stimulating for females. The eye-tracking metrics data showed a significant effect of swiping direction on fixation duration (p = 0.047) and a non-significant effect on pupil diameter (p = 0.576). These results were consistent with the results of the subjective preference questionnaire, both demonstrating a preference for vertical swiping among participants.

Discussion

This paper uses three research tools simultaneously, combining objective perceptions as well as subjective preferences, to make the findings more comprehensive and reliable. Gender differences were also taken into account and differentiated in the data processing. The findings of this paper are different from most previous studies and better reflect the preference of elderly people for swiping directions, which can provide a reference for the future elderly-friendly smart home interface design.

Analysing Touchscreen Gestures: A Study Based on Individuals with Down Syndrome Centred on Design for All

There has been a conscious shift towards developing increasingly inclusive applications. However, despite this fact, most research has focused on supporting those with visual or hearing impairments and less attention has been paid to cognitive impairments. The purpose of this study is to analyse touch gestures used for touchscreens and identify which gestures are suitable for individuals living with Down syndrome (DS) or other forms of physical or cognitive impairments. With this information, app developers can satisfy Design for All (DfA) requirements by selecting adequate gestures from existing lists of gesture sets. Twenty touch gestures were defined for this study and a sample group containing eighteen individuals with Down syndrome was used. A tool was developed to measure the performance of touch gestures and participants were asked to perform simple tasks that involved the repeated use of these twenty gestures. Three variables are analysed to establish whether they influence the success rates or completion times of gestures, as they could have a collateral effect on the skill with which gestures are performed. These variables are Gender, Type of Down syndrome, and Socioeconomic Status. Analysis reveals that significant difference is present when a pairwise comparison is performed, meaning individuals with DS cannot perform all gestures with the same ease. The variables Gender and Socioeconomic Status do not influence success rates or completion times, but Type of DS does.

Effects of control-to-display gain and operation precision requirement on touchscreen operations in vibration environments

Touchscreen has gained increasing popularity. However, little is known about touchscreen use in vibration environments. This study aimed to examine the effects of control-to-display gain (GAIN) and operation precision requirement on touchscreen operations in varied vibration environments. Twenty participants attended an experiment where they were instructed to perform three types of basic touchscreen operation tasks in static, low vibration, and high vibration environments, respectively. Five GAINs (0.75, 1, 2, 3 and 4) and three operation precision requirements (90%, 95%, and 99%) were examined. The results indicated that vibration exerted adverse effects on task performance, and increased perceived workload, perceived task difficulty and discomfort. Task completion time showed a U-shaped curve as GAIN increased. Lowering operation precision requirement improved task performance and reduced perceived workload, especially in vibration environments and at larger GAINs. The findings provide practical implications on the design of usable touchscreen interfaces in vibration environments.

Investigation of force, contact area and dwell time in finger-tapping tasks on membrane touch interface

This study aimed to determine the touch characteristics during tapping tasks on membrane touch interface and investigate the effects of posture and gender on touch characteristics variables. One hundred participants tapped digits displayed on a membrane touch interface on sitting and standing positions using all fingers of the dominant hand. Touch characteristics measures included average force, contact area and dwell time. Across fingers and postures, males exerted larger force and contact area than females, but similar dwell time. Across genders and postures, thumb exerted the largest force and the force of the other four fingers showed no significant difference. The contact area of the thumb was the largest, whereas that of the little finger was the smallest; the dwell time of the thumb was the longest, whereas that of the middle finger was the shortest. Relationships among finger sizes, gender, posture and touch characteristics were proposed. The findings helped direct membrane touch interface design for digital and numerical control products from hardware and software perspectives. Practitioner Summary: This study measured force, contact area and dwell time in tapping tasks on membrane touch interface and examined effects of gender and posture on force, contact area and dwell time. The findings will direct membrane touch interface design for digital and numerical control products from hardware and software perspectives. Abbreviations: M: mean; SD: standard deviation; ISO: International Organization for Standardization; LCD: liquid crystal display; ANOVA: analysis of variance; ANSI: American National Standards Institute; HFES: Human Factors and Ergonomics Society.

Tablet form factors and swipe gesture designs affect thumb biomechanics and performance during two-handed use

Tablet computers' hardware and software designs may affect upper extremity muscle activity and postures. This study investigated the hypothesis that forearm muscle activity as well as wrist and thumb postures differ during simple gestures across different tablet form factors and touchscreen locations. Sixteen adult (8 female, 8 male) participants completed 320 tablet gestures across four swipe locations, with various tablet sizes (8″ and 10"), tablet orientations (portrait and landscape), swipe orientations (vertical and horizontal), and swipe directions (medial and radial). Three-dimensional motion analysis and surface electromyography measured wrist and thumb postures and forearm muscle activity, respectively. Postures and muscle activity varied significantly across the four swipe locations (p < .0001). Overall, swipe location closest to the palm allowed users to swipe with a more neutral thumb and wrist posture and required less forearm muscle activity. Greater thumb extension and abduction along with greater wrist extension and ulnar deviation was required to reach the target as the target moved farther from the palm. Extensor Carpi Radialis, Extensor Carpi Ulnaris, Flexor Carpi Ulnaris, Extensor Policis Brevis, and Abductor Pollicis Longus muscle activity also increased significantly with greater thumb reach (p < 001). Larger tablet size induced greater Extensor Carpi Radialis, Extensor Carpi Ulnaris, Flexor Carpi Ulnaris, Flexor Carpi Radialis, and Abductor Pollicis Longus muscle activity (p < .0001). The study results demonstrate the importance of swipe locations and suggest that the tablet interface design can be improved to induce more neutral thumb and wrist posture along with lower forearm muscle load.