Saraç Stroppa, Mine
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Name Variants
Saraç Stroppa, Mine
Saraç M.
Sarac Stroppa, Mine
Saraç Stroppa,M.
SARAÇ STROPPA, Mine
Sarac Stroppa,Mine
Mine Saraç Stroppa
MINE SARAÇ STROPPA
Saraç Stroppa, MINE
Sarac Stroppa,M.
S.,Mine
M. Saraç Stroppa
Mine SARAÇ STROPPA
Saraç Stroppa, M.
S., Mine
Mine, Sarac Stroppa
SARAÇ STROPPA, MINE
Sarac, Mine
Stroppa, Mine Saraç
Stroppa, Mine Sarac
Saraç M.
Sarac Stroppa, Mine
Saraç Stroppa,M.
SARAÇ STROPPA, Mine
Sarac Stroppa,Mine
Mine Saraç Stroppa
MINE SARAÇ STROPPA
Saraç Stroppa, MINE
Sarac Stroppa,M.
S.,Mine
M. Saraç Stroppa
Mine SARAÇ STROPPA
Saraç Stroppa, M.
S., Mine
Mine, Sarac Stroppa
SARAÇ STROPPA, MINE
Sarac, Mine
Stroppa, Mine Saraç
Stroppa, Mine Sarac
Job Title
Dr. Öğr. Üyesi
Email Address
mine.sarac@khas.edu.tr
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Scholarly Output
18
Articles
3
Citation Count
0
Supervised Theses
2
18 results
Scholarly Output Search Results
Now showing 1 - 10 of 18
Conference Object Effect of Hand and Object Visibility in Navigational Tasks Based on Rotational and Translational Movements in Virtual Reality(Ieee Computer Soc, 2024) Batmaz, Anıl Ufuk; Saraç Stroppa, Mine; Batmaz, Anil Ufuk; Sarac, MineDuring object manipulation in Virtual Reality (VR) systems, realistically visualizing avatars and objects can hinder user performance and experience by complicating the task or distracting the user from the environment due to possible occlusions. Users might feel the urge to go through biomechanical changes, such as re-positioning the head to visualize the interaction area. In this paper, we investigate the effect of hand avatar and object visibility in navigational tasks using a VR headset. We performed two user studies where participants grasped a small, cylindrical object and navigated it through the virtual obstacles performing rotational or translational movements. We used three different visibility conditions for the hand avatar (opaque, transparent, and invisible) and two conditions for the object (opaque and transparent). Our results indicate that participants performed faster and with fewer collisions using the invisible and transparent hands compared to the opaque hand and fewer collisions with the opaque object compared to the transparent one. Furthermore, participants preferred to use the combination of the transparent hand avatar with the opaque object. The findings of this study might be useful to researchers and developers in deciding the visibility/transparency conditions of hand avatars and virtual objects for tasks that require precise navigational activities.Conference Object The Impact of Haptic Feedback During Sudden, Rapid Virtual Interactions(Ieee, 2023) Batmaz, Anıl Ufuk; Saraç Stroppa, Mine; Batmaz, Anil U.; Leonardis, Daniele; Sarac, MineHaptic feedback is known to improve the realism and the performance of virtual tasks during manipulation or teleoperation tasks. However, these benefits might depend on the nature of virtual tasks or the intensity of haptic rendering. In this paper, we focused on the impact of the presence and the intensity of the haptic stimulus during sudden, rapid virtual interactions through a variation of an ISO 9241:411 - task instead of calm, exploration-based interactions. We conducted a user study where the haptic stimulus is rendered through a realistic 1-DoF fingertip haptic device with different intensity levels (full-strength, half-strength, and no-strength) as they are asked to choose highlighted targets on a 6-by-5 grid as fast and correctly as possible. Our results show that haptic feedback did not significantly affect user performance regarding time, throughput, or the nature of the selection behavior. However, participants made significantly more errors when haptic feedback was present in half-strength compared to full-strength and no-strength conditions. In the post-experiment questionnaire, participants reported having favored haptic feedback in full strength in terms of perceived realism, enjoyment, and immersion.Conference Object Eye-Hand Coordination Training: a Systematic Comparison of 2d, Vr, and Ar Display Technologies and Task Instructions(Ieee Computer Soc, 2024) Aliza, Aliza; Batmaz, Anıl Ufuk; Zaugg, Irene; Saraç Stroppa, Mine; Celik, Elif; Stuerzlinger, Wolfgang; Ortega, Francisco Raul; Batmaz, Anil Ufuk; Sarac, MinePrevious studies on Eye-Hand Coordination Training (EHCT) focused on the comparison of user motor performance across different hardware with cross-sectional studies. In this paper, we compare user motor performance with an EHCT setup in Augmented Reality (AR), Virtual Reality (VR), and on a 2D touchscreen display in a longitudinal study. Through a ten-day user study, we thoroughly analyzed the motor performance of twenty participants with five task instructions focusing on speed, error rate, accuracy, precision, and none. As a novel evaluation criterion, we also analyzed the participants' performance in terms of effective throughput. The results showed that each task instruction has a different effect on one or more psychomotor characteristics of the trainee, which highlights the importance of personalized training programs. Regarding different display technologies, the majority of participants could see more improvement in VR than in 2D or AR. We also identified that effective throughput is a good candidate for monitoring overall motor performance progress in EHCT systems.Conference Object Subtask-Based Virtual Hand Visualization Method for Enhanced User Accuracy in Virtual Reality Environments(Ieee Computer Soc, 2024) Voisard, Laurent; Batmaz, Anıl Ufuk; Hatira, Amal; Saraç Stroppa, Mine; Bashar, Mohammad Raihanul; Gemici, Mucahit; Sarac, Mine; Kersten-Oertel, Marta; Batmaz, Anil UfukIn the virtual hand interaction techniques, the opacity of the virtual hand avatar can potentially obstruct users' visual feedback, leading to detrimental effects on accuracy and cognitive load. Given that the cognitive load is related to gaze movements, our study focuses on analyzing the gaze movements of participants across opaque, transparent, and invisible hand visualizations in order to create a new interaction technique. For our experimental setup, we used a Purdue Pegboard Test with reaching, grasping, transporting, and inserting subtasks. We examined how long and where participants concentrated on these subtasks and, using the findings, introduced a new virtual hand visualization method to increase accuracy. We hope that our results can be used in future virtual reality applications where users have to interact with virtual objects accurately.Article Hand Dominance and Congruence for Wrist-Worn Haptics Using Custom Voice-Coil Actuation(Ieee-inst Electrical Electronics Engineers inc, 2024) Saraç Stroppa, Mine; Sen, Umit; Ercan, Samet Mert; Sarac, MineDuring virtual interactions, rendering haptic feedback on a remote location (like the wrist) instead of the fingertips frees users' hands from mechanical devices. This allows for real interactions while still providing information about the mechanical properties of virtual objects. In this letter, we investigate the impact of using the dominant or non-dominant hand for virtual interactions and the best mapping between the active hand and the wrist receiving the haptic feedback, which can be defined as hand-wrist congruence through a user experiment based on a stiffness discrimination task. To render force feedback, we present CoWrHap - a novel wrist-worn haptic device with custom-made voice coil actuation. Our results show that participants performed the tasks (i) better with non-congruent mapping but reported better experiences with congruent mapping, and (ii) with no statistical difference in terms of hand dominance but with better user experience (enjoyment, pleasantness, etc.) using their dominant hands.Conference Object Re-Investigating the Effect of the Vergence-Accommodation Conflict on 3d Pointing(Assoc Computing Machinery, 2023) Batmaz, Anil Ufuk; Batmaz, Anıl Ufuk; Turkmen, Rumeysa; Saraç Stroppa, Mine; Sarac, Mine; Machuca, Mayra Donaji Barrera; Stuerzlinger, WolfgangThe vergence-accommodation conflict (VAC) limits user performance in current Virtual Reality (VR) systems. In this paper, we investigate the effects of the VAC in a single-focal VR system using three experimental conditions: with no VAC, with a constant VAC, and with a varying VAC. Previous work in this area had yielded conflicting results, so we decided to re-investigate this issue. Eighteen participants performed an ISO 9241:411 task in a study that closely replicates previous work, except that the angle of the task space was rotated 20 degrees downward, to make the task less fatiguing to perform, which addresses a potential confound in previous work. We found that the varying VAC condition had worse performance than the other conditions, which indicates that the contrasting results in previous work were very likely due to biomechanical factors. We hope that our work contributes to the understanding of the influence of the VAC in VR systems and potential strategies for improving user experience and performance in immersive virtual environments.Conference Object Effects of Opaque, Transparent and Invisible Hand Visualization Styles on Motor Dexterity in a Virtual Reality Based Purdue Pegboard Test(Ieee Computer Soc, 2023) Voisard, Laurent; Batmaz, Anıl Ufuk; Hatira, Amal; Saraç Stroppa, Mine; Sarac, Mine; Kersten-Oertel, Marta; Batmaz, Anil UfukThe virtual hand interaction technique is one of the most common interaction techniques used in virtual reality (VR) systems. A VR application can be designed with different hand visualization styles, which might impact motor dexterity. In this paper, we aim to investigate the effects of three different hand visualization styles transparent, opaque, and invisible - on participants' performance through a VR-based Purdue Pegboard Test (PPT). A total of 24 participants were recruited and instructed to place pegs on the board as quickly and accurately as possible. The results indicated that using the invisible hand visualization significantly increased the number of task repetitions completed compared to the opaque hand visualization. However, no significant difference was observed in participants' preference for the hand visualization styles. These findings suggest that an invisible hand visualization may enhance performance in the VR-based PPT, potentially indicating the advantages of a less obstructive hand visualization style. We hope our results can guide developers, researchers, and practitioners when designing novel virtual hand interaction techniques.Conference Object Haptic Feedback Relocation From the Fingertips To the Wrist for Two-Finger Manipulation in Virtual Reality(IEEE, 2022) Palmer, Jasmin E.; Saraç Stroppa, Mine; Sarac, Mine; Garza, Aaron A.; Okamura, Allison M.Relocation of haptic feedback from the fingertips to the wrist has been considered as a way to enable haptic interaction with mixed reality virtual environments while leaving the fingers free for other tasks. We present a pair of wrist-worn tactile haptic devices and a virtual environment to study how various mappings between fingers and tactors affect task performance. The haptic feedback rendered to the wrist reflects the interaction forces occurring between a virtual object and virtual avatars controlled by the index finger and thumb. We performed a user study comparing four different finger-totactor haptic feedback mappings and one no-feedback condition as a control. We evaluated users' ability to perform a simple pick-and-place task via the metrics of task completion time, path length of the fingers and virtual cube, and magnitudes of normal and shear forces at the fingertips. We found that multiple mappings were effective, and there was a greater impact when visual cues were limited. We discuss the limitations of our approach and describe next steps toward multi-degreeof-freedom haptic rendering for wrist-worn devices to improve task performance in virtual environments.Article Touch To Learn: a Review of Haptic Technology's Impact on Skill Development and Enhancing Learning Abilities for Children(Wiley, 2024) Hatira, Amal; Saraç Stroppa, Mine; Sarac, MineEarly childhood education is critical in shaping children's intellectual and motor skills as it provides a solid foundation for cognitive, social, and emotional development, which highly depends on spatial thinking. Haptic feedback can be effectively used for educational and training purposes, particularly in fields such as physics, math, and arts, offering a more interactive learning media and supporting kinesthetic learners by its nature. Herein, different ways of implementing haptic feedback on different educational scenarios from the perspective of technological development and their impact on children's learned skills and outcomes (e.g., their motivation, their analytical or spatial thinking abilities, or fine motor skills) will be examined. This article provides an overview of how haptic feedback has been implemented in different learning scenarios for children. Particularly, it is indicated that haptics can potentially improve early childhood learning outcomes and spatial reasoning skills as it can increase children's interest, participation, performance in educational activities, and analytical ability. The major drawbacks of the current studies, such as variance in participants' learning challenges and small sample numbers are also highlighted. Haptic feedback can be used for educationand training , offering a more interactive learning media and supporting kinesthetic learners by its nature. Herein, we provide an overview of how haptic feedback has been implemented in different learning scenarios for children from the perspective of technological development and their impact on learned skills, achieved motivation, thinking abilities, or fine motor skills.image (c) 2024 WILEY-VCH GmbHReview Optimizing Exoskeleton Design with Evolutionary Computation: An Intensive Survey(Mdpi, 2023) Stroppa, Fabıo; Saraç Stroppa, Mine; Yuksel, Huseyin Taner; Akbas, Baris; Sarac, MineExoskeleton devices are designed for applications such as rehabilitation, assistance, and haptics. Due to the nature of physical human-machine interaction, designing and operating these devices is quite challenging. Optimization methods lessen the severity of these challenges and help designers develop the device they need. In this paper, we present an extensive and systematic literature search on the optimization methods used for the mechanical design of exoskeletons. We completed the search in the IEEE, ACM, and MDPI databases between 2017 and 2023 using the keywords exoskeleton, design, and optimization. We categorized our findings in terms of which limb (i.e., hand, wrist, arm, or leg) and application (assistive, rehabilitation, or haptic) the exoskeleton was designed for, the optimization metrics (force transmission, workspace, size, and adjustability/calibration), and the optimization method (categorized as evolutionary computation or non-evolutionary computation methods). We discuss our observations with respect to how the optimization methods have been implemented based on our findings. We conclude our paper with suggestions for future research.
