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Self-quantification, with the promise of motivating consumers to engage in health behaviors through measuring their performance, is a popular trend amongst consumers. Despite the economic impact of self-tracking technologies, consumers' experiences with self-tracking devices and corresponding consequences for firms remain understudied. Six studies examine how the popular marketing tactic of anthropomorphization influences (a) consumers' favorability towards wearable tracking devices, (b) their health motivation, and (c) their health behavior (number of steps taken) over time. The authors uncover a novel dynamic effect of anthropomorphism, such that with use, the initially positive evaluations of anthropomorphized (vs. non-anthropomorphized) devices decrease, and (contrary to prior literature), anthropomorphized devices are not favored. Importantly, health motivation and health behaviors are also reduced over time with the use of an anthropomorphized (vs. non-anthropomorphized) wearable device. This decrease occurs because anthropomorphized devices reduce the wearers' perceived autonomy, which in turn, reduces their health motivation and health behavior. However, customizing the anthropomorphized device (by setting a customized goal or by monitoring a greater number of health-related indicators) can mitigate its negative effects. These findings provide novel insights to marketing scholars and managers, by suggesting that anthropomorphism can be a successful short-term selling strategy, but over time, it can have unintended consequences for both firms and consumers., Author(s): Lane Peterson Fronczek [sup.1] , Martin Mende [sup.2] , Maura L. Scott [sup.2] , Gergana Y. Nenkov [sup.3] , Anders Gustafsson [sup.4] [sup.5] Author Affiliations: (1) grid.256304.6, 0000 0004 [...]

With efficiencies derived from evolution, growth and learning, humans are very well-tuned for locomotion (1). Metabolic energy used during walking can be partly replaced by power input from an exoskeleton (2), but is it possible to reduce metabolic rate without providing an additional energy source? This would require an improvement in the efficiency of the human-machine system as a whole, and would be remarkable given the apparent optimality of human gait. Here we show that the metabolic rate of human walking can be reduced by an unpowered ankle exoskeleton. We built a lightweight elastic device that acts in parallel with the user's calf muscles, off-loading muscle force and thereby reducing the metabolic energy consumed in contractions. The device uses a mechanical clutch to hold a spring as it is stretched and relaxed by ankle movements when the foot is on the ground, helping to fulfil one function of the calf muscles and Achilles tendon. Unlike muscles, however, the clutch sustains force passively. The exoskeleton consumes no chemical or electrical energy and delivers no net positive mechanical work, yet reduces the metabolic cost of walking by 7.2 [+ or -] 2.6% for healthy human users under natural conditions, comparable to savings with powered devices. Improving upon walking economy in this way is analogous to altering the structure of the body such that it is more energy-effective at walking. While strong natural pressures have already shaped human locomotion, improvements in efficiency are still possible. Much remains to be learned about this seemingly simple behaviour., Humans are skilled walkers. Over generations, our bodies have evolved muscular (1), skeletal (3) and neural (4) systems well-suited to locomotion. We learn and embed walking coordination strategies over our [...]

Should we give moral standing to machines? In this paper, I explore the implications of a relational approach to moral standing for thinking about machines, in particular autonomous, intelligent robots. I show how my version of this approach, which focuses on moral relations and on the conditions of possibility of moral status ascription, provides a way to take critical distance from what I call the 'standard' approach to thinking about moral status and moral standing, which is based on properties. It does not only overcome epistemological problems with the standard approach, but can also explain how we think about, experience, and act towards machines--including the gap that sometimes occurs between reasoning and experience. I also articulate the non-Cartesian orientation of my 'relational' research program and specify the way it contributes to a different paradigm in thinking about moral standing and moral knowledge. Keywords Moral standing * Moral status * Moral relations * Moral knowledge * Robots * Machines * Descartes * Levinas: modernity * Moral change * Phenomenology, 1 Introduction In fields such as the military and space exploration, but also in health care and households, humans are increasingly confronted with robots. Humans are assisted by robots and [...]

One of the enduring concerns of moral philosophy is deciding who or what is deserving of ethical consideration. This special issue of Philosophy and Technology investigates whether and to what extent machines, of various designs and configurations, can or should be considered moral subjects, defined here as either a moral agent, a moral patient, or both. The articles that comprise the issue were competitively selected from papers initially prepared for and presented at a symposium on this subject matter convened during the AISB/IACAP 2012 World Congress, held in at the University of Birmingham in Birmingham, UK. Keywords Artificial intelligence * Ethics * Moral agency * Moral patiency * Roboethics, Moral philosophy, although historically defined in different ways by different intellectual traditions, is essentially about intersubjectivity. That is, it concerns actions between and involving at least two entities. 'When reduced [...]

When it comes to the question of what kind of moral claim an intelligent or autonomous machine might have, one way to answer this is by way of comparison with humans: Is there a fundamental difference between humans and other entities? If so, on what basis, and what are the implications for science and ethics? This question is inherently imprecise, however, because it presupposes that we can readily determine what it means for two types of entities to be sufficiently different--what I will refer to as being 'discontinuous'. In this paper, I will sketch a formal characterization of what it means for types of entities to be unique with regard to each other. This expands upon Bruce Mazlish's initial formulation of what he terms a continuity between humans and machines, Alan Turing's epistemological approach to the question of machine intelligence, and Sigmund Freud's notion of scientific revolutions dealing blows to the self-esteem of mankind. I will discuss on what basis we should regard entities as (dis-)continuous, the corresponding moral and scientific implications, as well as an important difference between what I term downgrading and upgrading continuities--a dramatic difference in how two previously discontinuous types of entities might become continuous. All of this will be phrased in terms of which scientific levels of explanation we need to presuppose, in principle or in practice, when we seek to explain a given type of entity. The ultimate purpose is to provide a framework that defines which questions we need to ask if we argue that two types of entities ought (not) to be explained (hence treated) in the same manner, as well as what it takes to reconsider scientific and ethical hierarchies imposed on the natural and artificial world. Keywords Continuity * Moral status * Levels of explanation * Artificial intelligence * Turing * Scientific revolutions, 1 Introduction The uniqueness and corresponding moral status of humans compared to other types of entities has been a central philosophical topic since ancient Greece, and our implicit or explicit [...]

In order to determine whether current (or future) machines have a welfare that we as agents ought to take into account in our moral deliberations, we must determine which capacities give rise to interests and whether current machines have those capacities. After developing an account of moral patiency, I argue that current machines should be treated as mere machines. That is, current machines should be treated as if they lack those capacities that would give rise to psychological interests. Therefore, they are moral patients only if they have non-psychological interests. I then provide an account of what I call teleo interests that constitute the most plausible type of nonpsychological interest that a being might have. I then argue that even if current machines have teleo interests, they are such that agents need not concern themselves with these interests. Therefore, for all intents and purposes, current machines are not moral patients. Keywords AI ethics * Moral status * Machine * Interests * Moral considerability, I Introduction On any reasonable account of who or what is a moral patient--i.e., who or what has a welfare that we must consider in our moral deliberations--once we create [...]

This essay responds to the machine question in the affirmative, arguing that artifacts, like robots, AI, and other autonomous systems, can no longer be legitimately excluded from moral consideration. The demonstration of this thesis proceeds in four parts or movements. The first and second parts approach the subject by investigating the two constitutive components of the ethical relationship--moral agency and patiency. In the process, they each demonstrate failure. This occurs not because the machine is somehow unable to achieve what is considered necessary and sufficient to be a moral agent or patient but because the characterization of agency and patiency already fail to accommodate others. The third and fourth parts respond to this problem by considering two recent alternatives--the all-encompassing ontocentric approach of Luciano Floridi's information ethics and Emmanuel Levinas's eccentric ethics of otherness. Both alternatives, despite considerable promise to reconfigure the scope of moral thinking by addressing previously excluded others, like the machine, also fail but for other reasons. Consequently, the essay concludes not by accommodating the alterity of the machine to the requirements of moral philosophy but by questioning the systemic limitations of moral reasoning, requiring not just an extension of rights to machines, but a thorough examination of the way moral standing has been configured in the first place. Keywords Artificial intelligence . Ethics . Machine ethics . Animal ethics . Information ethics, 1 Introduction One of the enduring concerns of moral philosophy is determining who or what is deserving of ethical consideration. Although initially limited to 'other men,' the practice of ethics [...]

Brain-computer interface (BCI) neurotechnology has the potential to reduce disability associated with paralysis by translating neural activity into control of assistive devices.sup.1-9. Surveys of potential end-users have identified key BCI system features.sup.10-14, including high accuracy, minimal daily setup, rapid response times, and multifunctionality. These performance characteristics are primarily influenced by the BCI's neural decoding algorithm.sup.1,15, which is trained to associate neural activation patterns with intended user actions. Here, we introduce a new deep neural network.sup.16 decoding framework for BCI systems enabling discrete movements that addresses these four key performance characteristics. Using intracortical data from a participant with tetraplegia, we provide offline results demonstrating that our decoder is highly accurate, sustains this performance beyond a year without explicit daily retraining by combining it with an unsupervised updating procedure.sup.3,17-20, responds faster than competing methods.sup.8, and can increase functionality with minimal retraining by using a technique known as transfer learning.sup.21. We then show that our participant can use the decoder in real-time to reanimate his paralyzed forearm with functional electrical stimulation (FES), enabling accurate manipulation of three objects from the grasp and release test (GRT).sup.22. These results demonstrate that deep neural network decoders can advance the clinical translation of BCI technology. Intracortical activity data recorded over 2 years in a tetraplegic patient is used to develop an artificial intelligence algorithm that achieves fast, accurate, and stable movement decoding to reenable real-time control of the paralyzed forearm., Author(s): Michael A. Schwemmer [sup.1] , Nicholas D. Skomrock [sup.1] , Per B. Sederberg [sup.2] , Jordyn E. Ting [sup.3] , Gaurav Sharma [sup.3] , Marcia A. Bockbrader [sup.4] [sup.5] [...]

WALKING SEEMS SO simple: Just put one foot in front of the other. Yet every step you take is a precarious act. When you walk, your body's center of mass [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.apergo.2010.03.005 Byline: Alan H.S. Chan, Ken W.L. Chan Abstract: This study investigated the performance of 24 participants in eight different three-dimensional spatial stimulus-response (S-R) mapping conditions. The stimulus visual signals were positioned at the corners of an imaginary cube, and responses were made by hands and feet. There was a significant interaction of visual signal position and response device position which demonstrated the existence of a strong spatial S-R compatibility effect in the task. Relatively faster reaction times and lower error percentages were obtained for the compatible S-R conditions. The spatial compatibility effect in the up-down dimension was the strongest, and the effect in the left-right dimension was stronger than the effect in the front-rear dimension. The findings of this study could be translated into practical and useful ergonomics recommendations for designing visual displays and control devices in three-dimensional space for improving overall human-machine system performance. Author Affiliation: Department of Manufacturing Engineering, and Engineering Management, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong Article History: Received 10 December 2008; Accepted 4 March 2010

Problem statement: Communication and control are two main components in any Mechatronics system. They can be designed either by centralized or decentralized approach. Both approaches can be chosen based on application designed and specific requirements of the designer. In this study, decentralized or normally called distributed approach was selected to solved communication and control of a human adaptive mechanical system namely Intelligent Chair Tools (ICT). The ICT seating system is powered by thirty six intelligent pneumatic actuators to facilitate investigation of chair shapes from spring and damping effect of seating and backrest surface. Three studies are proposed from the sitting experiments namely chair shapes, chair spring and chair damping properties. Approach: PSoC microcontroller was selected based on its features of having configurable analog and digital blocks. Its flexible modules and programmable peripherals ease designer in designing the communication and control of ICT in improved and faster way. Three protocols of USB, SPI and [I.sup.2]C were used for the communication system of ICT using PSoC. Flow charts of each communication protocols algorithms were discussed. On the other hand, the control system used PSoC's ADC and counter modules to read inputs of pressure and encoder respectively. PWM module is used to control the valve and data communication was achieved using [I.sup.2]C module. Block diagram of unified control was discussed for further understandings of the control algorithms. Results: The PSoC specification, development design and experimental evaluation of ICT system are presented and discussed. Three studies of chair shapes, chair spring property and chair damping property from sitting experiment were shown. Conclusion/Recommendations: The PSoC microcontroller selection was discussed and application of its distributed communication and control was successfully applied to ICT. This distributed approach can be applied to other application suitable for local control approach for easy debugging, more modular design and intelligence in deciding output based on feedback inputs. Key words: Distributed communication and control, PSoC, human machine interaction, ergonomics, INTRODUCTION Programmable System on Chip (PSoC) represents a whole new concept in microcontroller development. The mixed signal arrays of Cypress integrate an 8 bit microcontroller with analogue and digital components [...]

Service robots used in human environments must be designed to avoid collisions with humans. A safe robot arm can be designed using active or passive compliance methods. A passive compliance system composed of purely mechanical elements often provides faster and more reliable responses for dynamic collision than an active one involving sensors and actuators. Because positioning accuracy and collision safety are equally important, a robot arm should have very low stiffness when subjected to a collision force that could cause human injury but should otherwise maintain very high stiffness. A novel safe joint mechanism (SJM) consisting of linear springs and a double-slider mechanism is proposed to address these requirements. The SJM has variable stiffness that can be achieved with only passive mechanical elements. Analyses and experiments on static and dynamic collisions show high stiffness against an external torque less than a predetermined threshold value and an abrupt drop in stiffness when the external torque exceeds this threshold. The SJM enables the robotic manipulator to guarantee positioning accuracy and collision safety and it is simple to install between an actuator and a robot link without a significant change in the robot's design. [DOI: 10.1115/1.4001666] Keywords: nonlinear stiffness, passive compliance, physical human-robot interaction, safety mechanism

Information retrieval research has demonstrated that system performance does not always correlate positively with user performance, and that users often assign positive evaluation scores to search systems even when they are unable to complete tasks successfully. This research investigated the relationship between objective measures of system performance and users' perceptions of that performance. In this study, subjects evaluated the performance of four search systems whose search results were manipulated systematically to produce different orderings and numbers of relevant documents. Three laboratory studies were conducted with a total of eighty-one subjects. The first two studies investigated the effect of the order of five relevant and five nonrelevant documents in a search results list containing ten results on subjects' evaluations. The third study investigated the effect of varying the number of relevant documents in a search results list containing ten results on subjects' evaluations. Results demonstrate linear relationships between subjects' evaluations and the position of relevant documents in a search results list and the total number of relevant documents retrieved. Of the two, number of relevant documents retrieved was a stronger predictor of subjects' evaluation ratings and resulted in subjects using a greater range of evaluation scores. Categories and Subject Descriptors: H.1.2. [Models and Principles]: User/Machine Systems-Human factors General Terms: Human Factors, Performance Additional Key Words and Phrases: Search performance, satisfaction, user evaluation of performance, precision, presentation of search results, ranking ACM Reference Format: Kelly, D., Fu, X., and Shah, C. 2010. Effects of position and number of relevant documents retrieved on users' evaluations of system performance. ACM Trans. Inf. Syst. 28, 2, Article 9 (May 2010), 29 pages. DOI 10.1145/1740592.1740597. http://doi.acm.org/10.1145/1740592.1740597

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.apergo.2009.04.011 Byline: Andrea Haarmann, Wolfram Boucsein, Florian Schaefer Abstract: Adaptive automation increases the operator's workload in case of hypovigilance and takes over more responsibility if workload becomes too high. Two consecutive studies were conducted to construct a biocybernetic adaptive system for a professional flight simulator, based on autonomic measures. Workload was varied through different stages of turbulences. In a first study with 18 participants, electrodermal responses of experimental subjects oscillated very close to the individual set point, demonstrating that workload level was adjusted as a result of adaptive control, which was not the case in yoked control subjects without adaptive automation. Combining electrodermal responses with heart rate variability in a second study with 48 participants further enhanced the adaptive power which was seen in even smaller set point deviations for the experimental compared to the yoked control group. We conclude that the level of arousal can be adjusted to avoid hypovigilance by combining autonomic measures in a closed loop. Author Affiliation: Physiological Psychology, University of Wuppertal, Max-Horkheimer-Str. 20, D-42119 Wuppertal, Germany Article History: Received 28 March 2008; Accepted 30 April 2009 Article Note: (footnote) [star] The rights of all subjects were protected and informed consent was obtained.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.apergo.2009.04.008 Byline: G. Robert J. Hockey, Peter Nickel, Adam C. Roberts, Michael H. Roberts Abstract: Complex systems are vulnerable to unpredictable breakdowns in operator performance. Although primary task goals are typically protected by compensatory effort, such protection may break down under fatigue and high strain. Detection of strain states would enable prediction of increased operational risk through adaptive automation, triggering a switch of control from human to computer. A simulated process control task was used to identify markers of strain under a cyclic loading procedure, which forced performance breakdown through stepwise changes in control load. Four trained participants provided data on control performance and a range of candidate psychophysiological markers of strain (two EEG power ratios and HRV). Within-individual analyses showed the strongest sensitivity for 'task load index' (TLI), an EEG measure based on executive control activity in frontal brain areas, though all measures were sensitive for some participants. The implications of such findings for the development of a closed loop system for adaptive automation are discussed. Author Affiliation: Department of Psychology, University of Sheffield, Sheffield S10 2TP, UK Article History: Received 30 January 2008; Accepted 21 April 2009

Everyone has probably experienced the phenomenon where their footsteps unconsciously synchronize with their partner while walking together. This interpersonal synchronization of body motion has been widely observed and is significant in the context of social psychology. However, the mechanism of this embodied cooperation still remains obscure and has not been substantially developed as an engineering application. In this study, by assuming "mutual entrainment" as an interpersonal synchronization mechanism, we establish a new cooperative walking system between a walking human and a walking robot (an agent as a virtual robot). In this system, rhythmic sounds corresponding to the timing of footsteps are exchanged between them on the basis of our previous studies. As a result, it was demonstrated that the two walking rhythms adapt mutually after the start of interaction, and stable synchronization is generated automatically. This global entrained state exhibits dynamic stability with small fluctuation in the walking period. Applying this method to walking support for Parkinson's disease and hemiplegia patients, its effectiveness in stabilizing the walking of the patient was shown. These results indicate the importance of interpersonal mutual entrainment of rhythmic motion for walking support, and new human-robot interaction technologies are expected as an extension of this framework. Index Terms--Human-robot interaction, mutual entrainment, walking support, Walk-Mate.

In a human--robot interface, the prediction of motion, which is based on context information of a task, has the potential to improve the robustness and reliability of motion classification to control prosthetic devices or human-assisting manipulators. This paper proposes a task model using a Bayesian network (BN) for motion prediction. Given information of the previous motion, this task model is able to predict occurrence probabilities of the motions concerned in the task. Furthermore, a hybrid motion classification framework has been developed based on the BN motion prediction. Besides the motion prediction, electromyogram (EMG) signals are simultaneously classified by a probabilistic neural network (NN). Then, the motion occurrence probabilities are combined with the NN classifier's outputs to generate motion commands for control. With the proposed motion classification framework, it is expected that classification performance can be enhanced so that motion commands can be more robust and reliable. Experiments have been conducted with four subjects to demonstrate the feasibility of the proposed methods. In these experiments, forearm motions are classified with EMG signals considering a cooking task. Finally, robot manipulation experiments were carried out to verify the proposed human interface system with a task of taking meal. The experimental results indicate that the proposed methods improved the robustness and stability of motion classification. Index Terms--Bayesian network (BN), electromyogram (EMG) signal, human--robot interfaces, motion classification, motion prediction.

The Sogang University biomedical assistive robot (SUBAR), which is an advanced version of the exoskeleton for patients and the old by Songang (EXPOS) is a wearable robot developed to assist physically impaired people. It provides a person with assistive forces controlled by human intentions. If a standard geared dc motor is applied, however, the control efforts will be used mainly to overcome the resistive forces caused by the friction, the damping, and the inertia in actuators. In this paper, such undesired properties are rejected by applying a flexible transmission. With the proposed method, it is intended that an actuator exhibits zero impedance without friction while generating the desired torques precisely. Since the actuation system of SUBAR has a large model variation due to human--robot interaction, a control algorithm for the flexible transmission is designed based on a robust control method. In this paper, the mechanical design of SUBAR, including the flexible transmission and its associated control algorithm, are presented. They are also verified by experiments. Index Terms--Exoskeleton, force-mode actuation, human-robot interaction, mechanical impedance.

In this paper, we report on the findings of a human-robot interaction study that aims at developing a communication language for transferring grasping skills from a nontechnical user to a robot. Participants with different backgrounds and education levels were asked to command a five-degree-of-freedom human-scale robot arm to grasp five small everyday objects. They were allowed to use either commands from an existing command set or develop their own equivalent natural language instructions. The study revealed several important findings. First, individual participants were more inclined to use simple, familiar commands than more powerful ones. In most cases, once a set of instructions was found to accomplish the grasping task, few participants deviated from that set. In addition, we also found that the participant's background does appear to play a role during the interaction process. Overall, participants with less technical backgrounds require more time and more commands on average to complete a grasping task as compared to participants with more technical backgrounds. Index Terms--Grasping, human-robot interaction, natural language instruction, skill transfer, user-adaptive robotics.

Human-interactive robots, such as those used for nursing, which share humans' environments and interact with them, should be covered with soft areal tactile sensors for safety and dexterous manipulation. We report the successful development of the tactile sensor system of our human-interactive robot named RI-MAN, which can lift up a dummy human. Index Terms--Human-interactive robots, tactile sensors, tactile systems.

An annotated data set is presented meant to help researchers in developing, evaluating, and comparing various approaches in robotics for building space representations appropriate for communicating with humans. The data consist of omnidirectional images, laser range scans, sonar readings, and robot odometry. A set of base-level human spatial concepts is used to annotate the data. Index Terms--Human-robot interaction, map building, robot space representation.

Byline: Ravi Vaidyanathan (University of Southampton, Southampton, UK Naval Postgraduate School, Monterey, CA, USA Case Western Reserve University, OH, USA rvaidyan@nps.edu); Monique P. Fargues (Naval Postgraduate School, Monterey, CA, USA); [...]

When humans learn a new motor skill from a teacher, they learn using multiple channels. They receive high level information aurally about the skill, visual information about how another performs the skill, and at times, tactile information from the teacher's physical guidance. This research proposes a novel approach where the student receives real-time tactile feedback, simultaneously over all joints, delivered through a wearable robotic system. This tactile feedback can supplement the visual or auditory feedback from the teacher. Our results using a 5-DOF robotic suit show a 27% improvement in accuracy while performing the target motion, and an accelerated learning rate of up to 23%. We report both of these results with high statistical significance (p [less than or equal to] 0.01). This research is intended for use in a diverse set of applications including sports training, motor rehabilitation after neurological damage, dance, postural retraining for health, and many others. We call this system tactile interaction for kinesthetic learning (TIKL). Index Terms--Human factors, intelligent tutoring systems, man-machine systems, robot tactile systems.

In this paper, we describe our own stance on a research area called 'Humatronics,' which aims at establishing a (more) symmetric interaction relationship between humans and computer systems. In particular, we will advocate a novel approach to understanding humans that is based on largely involuntary and unconscious physiological information and gaze behavior rather than purposeful and conscious actions or behaviors. 'Understanding humans' here refers to users' states related to emotion and affect, attention and interest, and possibly even to their intentions. A key feature of our approach is that it provides insight into a person's cognitive-motivational state without relying on cognitive judgements, such as answers to dedicated queries. Lifelike interface agents are endowed with synthetic bodies and faces and can be considered as prime candidates for outbalancing the asymmetric relationship in current human--computer interaction. As example applications, we will report on two recent studies that utilized lifelike agents as presenters or interaction partners of users. The resulting interactions can be conceived c as implementing initial steps toward symmetric multimodality in user interfaces. Index Terms--User interface human factors.

Computer-generated anthropomorphic characters are a growing type of communicator that is deployed in digital communication environments. An essential theoretical question is how people identify humanlike but clearly artificial, hence humanoid, entities in comparison to natural human ones. This identity categorization inquiry was approached under the framework of consistency and tested through examining inconsistency effects from mismatching categories. Study 1 (N = 80), incorporating a self-disclosure task, tested participants' responses to a talking-face agent, which varied in four combinations of human versus humanoid faces and voices. In line with the literature on inconsistency, the pairing of a human face with a humanoid voice or a humanoid face with a human voice led to longer processing rime in making judgment of the agent and less trust than the pairing of a face and a voice from either the human or the humanoid category. Female users particularly showed negative attitudes toward inconsistently paired talking faces. Study 2 (N = 80), using a task that stressed comprehension demand, replicated the inconsistency effects on judging rime and females' negative attitudes but not for comprehension-related outcomes. Voice clarity overshadowed the consistency concern for comprehension-related responses. The overall inconsistency effects suggest that people treat humanoid entities in a different category from natural human ones. doi:10.1111/j.1468-2958.2007.00295.x

Visual interpretation of gestures can be useful in accomplishing natural human-robot interaction (HRI). Previous HRI research focused on issues such as hand gestures, sign language, and command gesture recognition. Automatic recognition of whole-body gestures is required in order for HRI to operate naturally. This presents a challenging problem, because describing and modeling meaningful gesture patterns from whole-body gestures is a complex task. This paper presents a new method for recognition of whole-body key gestures in HRI. A human subject is first described by a set of features, encoding the angular relationship between a dozen body parts in 3-D. A feature vector is then mapped to a codeword of hidden Markov models. In order to spot key gestures accurately, a sophisticated method of designing a transition gesture model is proposed. To reduce the states of the transition gesture model, model reduction which merges similar states based on data-dependent statistics and relative entropy is used. The experimental results demonstrate that the proposed method can be efficient and effective in HRI, for automatic recognition of whole-body key gestures from motion sequences. Index Terms--Gesture spotting, hidden Markov model (HMM), human-robot interaction (HRI), mobile robot, transition gesture model, whole-body gesture recognition.

This paper describes a spatial-motion-constraints-generation approach for a human-machine collaborative surgical-assistant system from registered computer tomography models. We extend constrained optimization formulation incorporating task goals, anatomy-based constraints, "no fly zones" etc. We use a fast potential-collision-constraint-detection method based on a 3-D surface model and covariance tree data structure. These boundary constraints, along with task behaviors and joint limits, serve as constraint conditions for constrained robot control. We are able to follow a complex path inside a human skull, phantom represented by a surface model composed of 99 000 vertices and 182 000 triangles in real time. Our approach enables real-time task-based control of a surgical robot in a precise interactive minimally invasive surgery task. We illustrate our approach based on two example tasks which are analogous to the procedures in endoscopic sinus surgery, and analyze the user's performance on both teleoperation and cooperative control for one of the example tasks. The experimental results show that a robotic assistant employing our approach on spatial motion constraints can assist the user in skilled manipulation tasks, while maintaining desired properties. Our approach is equally applicable to teleoperative and cooperative controlled robots. Index Terms--Anatomy-based constraint, optimization robot control, surgical robot assistant, virtual fixtures (VFs).