Conveying emotions via touch (i.e., affective touch) is a crucial part of social interaction and bonding. Socially assistive robots have widely used affective touch. However, drones being aerial robots, touch has only been explored as input for control, navigation, or command. Thus, this work investigates the potential of affective touch using a perched socially assistive drone. We address two critical topics: (1) using affective touch as a modality with drones and (2) implementing effective touch gestures for emotional communication with drones. In an user study (N = 30), we explored participants’ preferences for interaction modalities and mapped touch gestures to emotions. Results show that touch was the most preferred modality. Afterward, participants selected touch gestures to convey 16 emotions to a drone. We determined which gesture best fits each emotion. Our work highlights the relevance of affective haptics and sheds light on the nature of touch gestures’ emotional conveyance in Human-Drone Interaction.

We investigated variable autonomy in a teleoperated robot navigation task within a simulated office environment, focusing on who controls the shift between levels of automation (LoA). Two switch control modes—human-initiated (HI) and robot-initiated (RI)—were examined. The study assessed whether these modes influence operators’ cognitive workload, situational awareness (SA), and task performance. The task involved two LoA conditions: teleoperation (low LoA) and remote monitoring (high LoA), while participants simultaneously performed a secondary task. Task performance was measured through completion time, collision rates, time spent in low LoA, and secondary task performance. Operator-related measures included workload National Aeronautics and Space Administration Task Load Index (NASA-TLX), trust, ease of use, and perceived SA. The results revealed a clear tradeoff between operational efficiency and situational awareness. The RI mode improved task efficiency and reduced workload but compromised SA, whereas HI mode enhanced SA at the cost of efficiency. These findings highlight the inherent tension between automation-driven performance gains and operator’s cognitive engagement. The study contributes to the understanding of variable autonomy in human–robot collaboration (HRC) and underscores the need to evaluate both operator experience and task performance when designing teleoperation systems for habituated environments.

Socially assistive robots (SARs) are becoming more prevalent in everyday life, emphasizing the need to make them socially acceptable and aligned with users’ expectations. Robots’ appearance impacts users’ behaviors and attitudes toward them. Therefore, product designers choose visual qualities to give the robot a character and to imply its functionality and personality. In this work, we sought to investigate the effect of cultural differences on Israeli and German designers’ perceptions of SARs’ roles and appearance in four different contexts: a service robot for an assisted living/retirement residence facility, a medical assistant robot for a hospital environment, a COVID-19 officer robot, and a personal assistant robot for domestic use. The key insight is that although Israeli and German designers share similar perceptions of visual qualities for most of the robotics roles, we found differences in the perception of the COVID-19 officer robot’s role and, by that, its most suitable visual design. This work indicates that context and culture play a role in users’ perceptions and expectations; therefore, they should be taken into account when designing new SARs for diverse contexts.

Socially assistive robots (SARs) aim to provide assistance through social interaction. Previous studies contributed to understanding users’ perceptions and preferences regarding existing commercially available SARs. Yet very few studies regarding SARs’ appearance used designated SAR designs, and even fewer evaluated isolated visual qualities (VQs). In this work, we aim to assess the effect of isolated VQs systematically. To achieve this, we first conducted market survey and deconstructed the VQs attributed to SARs. Then, a reconstruction of body structure, outline, and color scheme was done, resulting in the creation of 30 new SAR models that differ in their VQs, allowing us to isolate one character at a time. We used these new designs to evaluate users’ preferences and perceptions in two empirical studies. Our empirical findings link VQs with perceptions of SAR characteristics. These can lead to forming guidelines for the industrial design processes of new SARs to match user expectations.

This study examines whether allowing a certain level of user customization of a socially assistive robot (SAR) affects users' perception of the robot and improves acceptance. Two hundred thirty-nine respondents participated in an online study of a telepresence-assistive robot. We formed three groups of respondents who differed in their ability to manipulate the SAR design. Results suggested that allowing mass customization positively affects users' acceptance of the SAR, perceived enjoyment, intention for future use, and perceived robot usefulness.

Digitization in the battlefield enables bi-directional graphic communication, i.e., sharing pictures or video feeds derived from unmanned systems, among distributed elements. Introducing robotic technologies at the battalion level is aimed to support shorter OODA (observe-orient-decide-act) cycles and more agility. Our focus is on developing bi-directional graphic communication tools for observer-executer teams as alternative ways to communicate. Following the Design Science Research methodology, four closely related consecutive studies with subject matter experts (SMEs) demonstrate how we first learn about phenomena and then use the knowledge to design interaction tools for communication. We first study the human-human observer-executer teams. Then, as the design of the interaction tools evolves, we transfer design principles into communication tools between an executer and the unmanned system (Wizard of Oz study). Our work highlights the potential of implementing and using bi-directional graphic communication to enhance battlefield understanding in addition to verbal communication (speech or chat). We demonstrate the necessity of user-centered development and evaluation for design and application. Further, we emphasize the role of the unmanned system operator (observer) and raise questions regarding how to further progress in teaming with intelligent unmanned systems.

Drivers of partially automated vehicles are relieved from parts of the driving tasks allocated to the automated driver. This reduction in driving demands encourages them to engage with nondriving related tasks, which may impair awareness of the road environment once a takeover request (TOR) is initiated. This article examined the four suggested strategies drivers that take to regain control following a TOR, from the perspective of interruption management principles. Thirty students participated in a simulated study of two drives, where we manipulated TOR alerts, time to regain control, and potential road hazards. We hypothesized that all four interruption management strategies will be observed. Our hypothesis was confirmed. Four strategies were identified. Most drivers chose strategy 2 toaccept and initiate the takeover immediatelyafter the TOR started. The second frequent strategy was toreject the TOR but look at the road. Drivers’ strategy choices changed following alert type and the chronological drive order. With simulated driving experience (i.e., second drive), drivers postponed taking control, adapting to the time budget. Yet, inaccurate understanding of the situation or over-trust affected the chosen strategy. We conclude that interruption management principles are beneficial for studying how drivers respond to TORs and evaluating options to improve TOR performance.

Caregivers in eldercare can benefit from telepresence robots that allow them to perform a variety of tasks remotely. In order for such robots to be operated effectively and efficiently by non-technical users, it is important to examine if and how the robotic system’s level of automation (LOA) impacts their performance. The objective of this work was to develop suitable LOA modes for a mobile robotic telepresence (MRP) system for eldercare and assess their influence on users’ performance, workload, awareness of the environment, and usability at two different levels of task complexity. For this purpose, two LOA modes were implemented on the MRP platform: assisted teleoperation (low LOA mode) and autonomous navigation (high LOA mode). The system was evaluated in a user study with 20 participants, who, in the role of the caregiver, navigated the robot through a home-like environment to perform control and perception tasks. Results revealed that performance improved in the high LOA when task complexity was low. However, when task complexity increased, lower LOA improved performance. This opposite trend was also observed in the results for workload and situation awareness. We discuss the results in terms of the LOAs’ impact on users’ attitude towards automation and implications on usability.

A socially assistive robot (SAR) can support children in developmental and well-being aspects. Children's tendency to anthropomorphize and pretend play contributes to their ability to engage with robots and establish relationships. The robot's visual aesthetics influences users' initial judgments and is essential for creating first impressions, trust, and desirability. SAR's visual appearance may lead the child to desired assumptions about its capabilities. Beyond aesthetics per se, designers must address the robots' visual qualities necessary to affect users' perceptions and expectations. This paper proposes and demonstrates a methodology for evaluating children's perception of visual qualities in SARs, aiming to pave the way for new design tools to support robotic designers and developers. Design tools can improve the SAR design process by forming means for designers and roboticists to consider and create a user experience for specific contexts, tasks, or use-case scenarios relevant to particular SARs. By this, to form the design of more use-oriented, acceptable, trustworthy, and desirable robots.

It is important to encourage older adults to remain active when interacting with assistive robots. This study proposes a schematic model for integrating levels of automation (LOAs) and transparency (LoTs) in assistive robots to match the preferences and expectations of older adults. Metrics to evaluate LOA and LoT design combinations are defined. We develop two distinctive test cases to examine interaction design considerations for robots working for this population in everyday tasks: a person-following task with a mobile robot and a table-setting task with a robot manipulator. Evaluations in user studies with older adults reveal that LOA and LoT combinations influence interaction elements. Low LOA and high LoT encouraged activity engagement while receiving adequate information regarding the robot's behavior. The variety of objective and subjective metrics is essential to provide a holistic framework for evaluating the interaction.

Real-time continuous workload assessment is important for researchers and developers of tools that aim to reduce human operators' cognitive workload, especially in dynamic environments, as the military environment, where task demands and workload change rapidly. Most workload measurement techniques provide a single retrospective value or require expensive high-end sensing equipment. This study aimed to introduce an affordable continuous machine learning (ML) based workload assessment tool, that can provide real-time workload scores. Using experienced military unmanned aerial vehicle (UAV) operators in a simulated operational setting, muscle behavior represented by their interaction with a joystick was modeled to predict Subjective Workload Assessment Technique (SWAT) scores. Data were obtained from six professional participants. Four machine learning (ML) modeling methodologies were tested on each participant's data. It has been shown that after running an ML setup phase for each participant, an already in use available tool as the UAV joystick controller can be used to predict SWAT scores at any given time. By implementing the approach presented in this study, researchers can more accurately evaluate various aspects of the human operator's cognitive workload, and developers can evaluate the progression of their solutions on operators' cognitive workload over time.

A detailed understanding of operator individual differences can serve as a foundation for developing a critical window on effective, adaptable, user-centered automation, and even for more autonomous systems. Adaptable automation that functions according to such principles and parameters has many potential benefits in increasing operator trust and acceptance of the automated system. Our current study provides an assessment of the way that individual differences in attentional control (AC) affect the preference for a selection of a desired level of automation (LOA). Participants who scored low or high on AC were either allowed to choose among four possible LOAs or restricted to a predetermined LOA. These manipulations were engaged while the operator was performing visual and auditory target detection tasks. The AC level was found to be inversely proportional to the LOA preference. Operators also performed better when they were preassigned to a fixed LOA rather than given a choice. Individual differences can thus be shown to affect the performance with the automated systems and should be considered in associated design processes. When deciding whether to give the operator control over LOA in a complex system, engineers should consider that the amount of control that operators may want does not necessarily reflect their actual needs.

Robots designed to support people in different tasks at home and in public areas need to be able to recognize user intentions and operate accordingly. To date, research has focused on developing the technological capabilities of the robot and the mechanism of recognition. Little is known about navigational commands that could be intuitively communicated by people in order to control a robot's movement. A two-part exploratory study was conducted to evaluate how people naturally guide the motion of a robot and whether an existing gesture vocabulary used for human-human communication can be applied to human-robot interaction. Fourteen participants were first asked to demonstrate ten different navigational commands while interacting with a Pioneer robot using a WoZ technique. In the second part of the study participants were asked to identify eight predefined commands from the U.S. Army vocabulary. The results of this study could serve as a baseline for future development of command vocabulary promoting a more natural and intuitive human-robot interaction style.

Body language of robot arms, have rarely been explored as a medium of conveying robot intentions. An explorative study was done focusing on two questions: one, if robot arm postures can convey robot intentions, and two, if participants coming in contact with this robot arm for the first time can associate any meaning to the postures without watching the robot in action, or working with it. Thirty five participants took part in this exploratory study. Results show significant effect of the design of postures on the interpretation of its meaning. Postures designed in tempered form of human/animal-like body language could successfully convey the desired intention to a significant number of people in the following categories: ‘Robot giving object in a friendly manner’; ‘Robot is saying Hi!’, ‘Robot has been told not to disturb’. Developers may predefine such postures in a robot to enhance its acceptability.

Robots that operate alongside people need to be able to move in socially acceptable ways. As a step toward this goal, we study how and under which circumstances the angle at which a robot follows a person may affect the human experience and robot tracking performance. In this paper, we aimed to assess three following angles (0° angle, 30° angle, and 60° angle) under two conditions: when the robot was carrying a valuable personal item or not. Objective and subjective indicators of the quality of following and participants' perceptions and preferences were collected. Results indicated that the personal item manipulation increased awareness to the quality of the following and the following angles. Without the manipulation, participants were indifferent to the behavior of the robot. Our following algorithm was successful for tracking at a 0° and 30° angle, yet it must be improved for wider angles. Further research is required to obtain better understanding of following angle preferences for varying environment and task conditions.

Tactical collision avoidance systems (TCAS) aim to promote aerospace safety by improving the situational awareness of helicopter pilots and reducing the likelihood of collisions. TCAS stimuli must be noticeable even with the multitude of visual and auditory stimuli the pilot must process during flight. To improve the salience of TCAS, a tactile on-thigh display component was added to the design. In a simulated task, participants were asked to conduct a flight mission, while searching for specific visual landmarks along the flight path and to respond to abrupt directional visual and/or tactile alerting cues. The addition of the tactile cues improved response accuracy and shortened response time to the warning. In addition, although it did not interfere with the ability to maintain flight control, participant recollection of the landmark targets they had identified was least successful in the presence of the tactile modality. Implications for design are discussed.

This study evaluated aesthetics and usability of in-vehicle electronic navigation maps. Experiment 1 examined map displays that varied in the amount of information presented, abstraction level, graphic/colour style and the existence of landmarks in both urban and rural environments using objective and subjective measures. Twenty participants performed navigation/localisation tasks using various map configurations while driving a driving simulator and completed usability and aesthetic questionnaires. The minimal detail map produced better performances and higher usability and aesthetic ratings when using maps with no landmarks. Adding information in the form of landmarks was found advantageous compared to additional textual information. Abstractions were most advantageous when combined with minimal amount of detail. Moderate abstractions were sufficient for obtaining the desired benefits when more details were present. The graphic/colour style affected subjective perceptions. Overall, high correlations were found for the perceived aesthetics and usability scales, however, low correlations were found between actual usability (i.e. performance) and perceived usability pointing to the importance of using both objective and subjective usability measures. Experiment 2 examined how maps varying in their aesthetic level (aesthetic versus non-aesthetic), different colour arrangements, and 2D versus 3D landmarks affect subjective and objective measures. Participants distinguished between usability and aesthetic perceptions and usability perceptions were less affected by aesthetics when the aesthetic level of the maps was low. Colour arrangement did not affect the measures examined. Both 2D and 3D landmarks were found to be aesthetic and usable. We conclude this article with guidelines for designing in-vehicle navigation map displays.

In two experiments participants had to detect changes in periodic sinusoidal functions, displayed in either graphic or tabular displays. Graphs had a major advantage over tables when the task required considering configurations of data. Both displays led to similar results when task performance could rely on inspecting individual data points. With graphs almost all participants reported using the optimal method for detecting changes in the function, i.e., they used the method requiring the least effort to perform the task. With tables only about half used the optimal detection method, and these participants showed transfer of learning of detection methods between tasks. Experience in using a detection method led to improved performance if the new task relied on the same method of detection. These findings demonstrate the need to consider task performance methods when determining the relative value of different displays. The set of tasks for which a display is used is likely to affect performance and needs to be analysed as a whole, since methods employed for one task can affect task performance in other tasks.

Three experiments examined the use of vibrotactile cues to guide an operator toward a target. Vibrotactile stimulation on the hand can provide spatially stabilizing cues for feedback of subtle changes in position. When such feedback is present, a deviation from the point of origin results in tactile stimulation indicating the direction and magnitude of the positional error. Likewise, spatial deviation from a desired position displayed tactually can provide robust position guidance and stabilization sufficient to improve the acquisition time and accuracy of fine cursor control. A major advantage of this mode of information representation is that it can be present at the same time as visual cues with minimal cross-modal interference. Our findings suggest that performance is actually enhanced when both tactile and visual cues are present. Although previous studies have suggested that various forms of tactile feedback can provide position guidance and stabilization, to our knowledge, this work is the first that details the effect of tactile feedback on target acquisition directly.