Biological movement increases acceptance of humanoid robots as human partners in motor interaction

The automatic tendency to anthropomorphize our interaction partners and make use of experience acquired in earlier interaction scenarios leads to the suggestion that social interaction with humanoid robots is more pleasant and intuitive than that with industrial robots. An objective method applied to evaluate the quality of human–robot interaction is based on the phenomenon of motor interference (MI). It claims that a face-to-face observation of a different (incongruent) movement of another individual leads to a higher variance in one’s own movement trajectory. In social interaction, MI is a consequence of the tendency to imitate the movement of other individuals and goes along with mutual rapport, sense of togetherness, and sympathy. Although MI occurs while observing a human agent, it disappears in case of an industrial robot moving with piecewise constant velocity. Using a robot with human-like appearance, a recent study revealed that its movements led to MI, only if they were based on human prerecording (biological velocity), but not on constant (artificial) velocity profile. However, it remained unclear, which aspects of the human prerecorded movement triggered MI: biological velocity profile or variability in movement trajectory. To investigate this issue, we applied a quasi-biological minimum-jerk velocity profile (excluding variability in the movement trajectory as an influencing factor of MI) to motion of a humanoid robot, which was observed by subjects performing congruent or incongruent arm movements. The increase in variability in subjects’ movements occurred both for the observation of a human agent and for the robot performing incongruent movements, suggesting that an artificial human-like movement velocity profile is sufficient to facilitate the perception of humanoid robots as interaction partners.     

Teaching a humanoid robot to draw ‘Shapes’

The core cognitive ability to perceive and synthesize ‘shapes’ underlies all our basic interactions with the world, be it shaping one’s fingers to grasp a ball or shaping one’s body while imitating a dance. In this article, we describe our attempts to understand this multifaceted problem by creating a primitive shape perception/synthesis system for the baby humanoid iCub. We specifically deal with the scenario of iCub gradually learning to draw or scribble shapes of gradually increasing complexity, after observing a demonstration by a teacher, by using a series of self evaluations of its performance. Learning to imitate a demonstrated human movement (specifically, visually observed end-effector trajectories of a teacher) can be considered as a special case of the proposed computational machinery. This architecture is based on a loop of transformations that express the embodiment of the mechanism but, at the same time, are characterized by scale invariance and motor equivalence. The following transformations are integrated in the loop: (a) Characterizing in a compact, abstract way the ‘shape’ of a demonstrated trajectory using a finite set of critical points, derived using catastrophe theory: Abstract Visual Program (AVP); (b) Transforming the AVP into a Concrete Motor Goal (CMG) in iCub’s egocentric space; (c) Learning to synthesize a continuous virtual trajectory similar to the demonstrated shape using the discrete set of critical points defined in CMG; (d) Using the virtual trajectory as an attractor for iCub’s internal body model, implemented by the Passive Motion Paradigm which includes a forward and an inverse motor model; (e) Forming an Abstract Motor Program (AMP) by deriving the ‘shape’ of the self generated movement (forward model output) using the same technique employed for creating the AVP; (f) Comparing the AVP and AMP in order to generate an internal performance score and hence closing the learning loop. The resulting computational framework further combines three crucial streams of learning: (1) motor babbling (self exploration), (2) imitative action learning (social interaction) and (3) mental simulation, to give rise to sensorimotor knowledge that is endowed with seamless compositionality, generalization capability and body-effectors/task independence. The robustness of the computational architecture is demonstrated by means of several experimental trials of gradually increasing complexity using a state of the art humanoid platform.     

Perceive this as that – Analogies, artificial perception, and category theory

This paper formalizes and analyzes cognitive transitions between artificial perceptions that consist of an analogical or metaphorical transference of perception. The formalization is performed within a mathematical framework that has been used before to formalize other aspects of artificial perception and cognition. The mathematical infrastructure consists of a basic category of ‘artificial perceptions’. Each ‘perception’ consists of a set of ‘world elements’, a set of ‘connotations’, and a three valued (true, false, undefined) predicative connection between the two sets. ‘Perception morphisms’ describe structure preserving paths between perceptions. Quite a few artificial cognitive processes can be viewed and formalized as perception morphisms or as other categorical constructs. We show here how analogical transitions can be formalized in a similar way. A factorization of every analogical transition is shown to formalize metaphorical perceptions that are inspired by the analogy. It is further shown how structural aspects of ‘better’ analogies and metaphors can be captured and evaluated by the same categorical setting, as well as generalizations that emerge from analogies. The results of this study are then embedded in the existing mathematical formalization of other artificial cognitive processes within the same premises. A fallout of the rigorous unified mathematical theory is that structured analogies and metaphors share common formal aspects with other perceptually acute cognitive processes. This revised version was published online in June 2006 with corrections to the Cover Date.     

SymGeons: A Prototype Model of Visual Complexity with Implications For Visual Control Tasks

The way in which humans perceive and react to visual complexity is an important issue in many areas of research and application, particularly because simplification of complex matter can lead to better understanding of both human behaviour in visual control tasks as well as the visual environment itself. One area of interest is how people perceive their world in terms of complexity and how this can be modelled mathematically and/or computationally. A prototype model of complexity has been derived using subcomponents called ‘SymGeons’ (Symmetrical Geometric Icons) based on Biederman’s original Geon Model for human perception. The SymGeons are primitive shapes which constitute foreground objects. This paper outlines the derivation and ongoing development of the ‘SymGeon’ model and how it compares to human perception of visual complexity. The application of the model to understanding complex human-in-the-loop problems associated with visual remote control operations, e.g. control of remotely operated vehicles, is discussed.     

Apostrophe, witnessing and its essentially theatrical modes of address: Maria Derm?ut on Pattimura and Kara Walker on the New Orleans flooding

Apostrophe is best known as a punctuation mark (’) or as a key poetic figure (with a speaker addressing an imaginary or absent person or entity). In origin, however, it is a pivotal rhetorical figure that indicates a ‘breaking away’ or turning away of the speaker from one addressee to another, in a different mode. In this respect, apostrophe is essentially theatrical. To be sure, the turn away implies two different modes of address that may follow upon one another, as is hinted at by the two meanings of the verb ‘to witness’: being a witness and bearing witness. One cannot do both at the same time. My argument will be, however, that in order to make witnessing work ethically and responsibly, the two modes of address must take place simultaneously, in the coincidence of two modalities of presence: one actual and one virtual. Accordingly, I will distinguish between an address of attention and an address of expression. Whereas the witness is actually paying attention to that which she witnesses, she is virtually (and in the sense Deleuze intended, no less really) turning away in terms of expression. The two come together in what Kelly Oliver called the ‘inner witness’. The simultaneous operation of two modes of address suggests that Caroline Nevejan’s so-called YUTPA model would have to include two modalities of ‘you’. Such a dual modality has become all the more important, in the context of the society of the spectacle. One text will help me first to explore two modes of address through apostrophe. I will focus on a story by Dutch author Maria Derm?ut, written in the fifties of the twentieth century, reflecting on an uprising and the subsequent execution of its leader in the Dutch Indies in 1817. Secondly, I will move to American artist Kara Walker’s response, in the shape of an installation and a visual essay, to the flooding of New Orleans in 2005. The latter will serve to illustrate a historic shift in the theatrical nature and status of ‘presence’ in the two modes of address. Instead of thinking of the convergence of media, of which Jenkins speaks, we might think of media swallowing up one another. For instance, the theatrical structure of apostrophe is swallowed up, and in a sense perverted, by the model of the spectacle in modern media. This endangers the very possibility of witnessing in any ethical sense of the word.     

Adaptation of robot’s perception of fuzzy linguistic information by evaluating vocal cues for controlling a robot manipulator

This article proposes a method for adapting a robot’s perception of fuzzy linguistic information by evaluating vocal cues. The robot’s perception of fuzzy linguistic information such as “very little” depends on the environmental arrangements and the user’s expectations. Therefore, the robot’s perception of the corresponding environment is modified by acquiring the user’s perception through vocal cues. Fuzzy linguistic information related to primitive movements is evaluated by a behavior evaluation network (BEN). A vocal cue evaluation system (VCES) is used to evaluate the vocal cues for modifying the BEN. The user’s satisfactory level for the robot’s movements and the user’s willingness to change the robot’s perception are identified based on a series of vocal cues to improve the adaptation process. A situation of cooperative rearrangement of the user’s working space is used to illustrate the proposed system by a PA-10 robot manipulator.     

Vibration perception and excitatory direction for haptic devices

Vibration feedback is one of the most popular ways to communicate between human and haptic interfaces nowadays. In order to deliver a wider variety of information accurately and efficiently, significant design factors of the vibration need to be investigated and applied to haptic devices. In this study, the excitatory direction was examined as a design factor of the vibration in terms of sensitivity and emotion. We conducted two experiments. In the first experiment, the sensitivities of three excitatory directions—X (lateral), Y (fore-and-aft) and Z (vertical) axes were estimated by the absolute thresholds of the vibration perception with two frequency levels (150 and 280 Hz). Based on ten participants’ estimated absolute thresholds, we conclude that the vibration with X axis is less sensitive than Z axis at the frequency of 150 Hz, while the vibration with Y axis is less sensitive than Z axis at the frequency of 280 Hz. In the second experiment, the agreeability of 29 emotional expressions to the vibrations was measured by a 7-point scale with a total of 12 conditions (2 frequencies × 2 amplitudes (i.e., 50 × 10⁻³ and 500 × 10⁻³ g) × 3 excitatory directions). Based on 20 participants’ responses, it is concluded that at the frequency of 150 Hz and the amplitude of 50 × 10⁻³ g, the vibration is perceived as ‘light’, and as even ‘lighter’ if the vibration is with Y axis rather than with Z axis. Likewise, at the frequency of 150 Hz and the amplitude of 500 × 10⁻³ g, the vibration is perceived as ‘repulsive’, and as even ‘more repulsive’ if the vibration is with Y or Z axis rather than with X axis. Therefore, three excitatory directions can be selectively utilized to design the distinguishable vibration by its sensitivity and emotion.     

Minimum effort factor approach for sensor-based control of a four-joint 6-dof redundant manipulator

A sensor-driven control model and a minimum effort control algorithm in terms of time and energy expended during the execution of a movement strategy are described and validated for a multijointed cooperating robotic manipulator. Considering smooth, human-like (anthropomorphic) movements, using joint motion profiles achievable in real time as well as sensory information from all joints, and evaluating the total work expended by each manipulator joint during the execution of a movement strategy, a minimum effort motion trajectory is synthesized to precisely and efficiently position the robotic arm end-effector. This sensor-based approach significantly reduces the computational requirements for such cooperative motion. The minimum effort control algorithm generates several human-like arm movement strategies and selects the best strategy on the basis of expendable effort. The algorithm has an inherent basis to deal with obstacles in an efficient way. Detailed examples are described from the simulation studies. © 1994 John Wiley & Sons, Inc.     

A new set of sufficient conditions based on coupling parameters for synchronization of Hopfield like Chaotic Neural Networks

In this paper, we consider a Hopfield like Chaotic Neural Networks which have both self-coupling and non-invertible activation functions. We show that the interactions between neurons can be used as a means of chaos generation or suppression to neuron’s outputs when more adaptability or stability is required. Furthermore, a new set of sufficient conditions based on coupling weights is proposed so that the synchronization of all neuron’s outputs with each other is guaranteed, when all neuron’s have identical activation functions. Finally, the effectiveness of the proposed approach is evaluated by performing simulations on three illustrative examples.     

A comparison of hand and foot movement times

Three experiments are reported in which a comparison is made between the times for movement of the hand and the foot. Both ballistic and visually-controlled movements were studied. It was found that execution time for foot movements is generally about twice as long as that for the equivalent arm movement. The times for foot movements were described well by the Welford, Norris and Shock modification of Fitts' Law for visually-controlled movements and, for ballistic movements, by the square-root-of-amplitude equation found by Hoffmann for arm movements.     

A fast algorithm for computing moments of gray images based on NAM and extended shading approach

Computing moments on images is very important in the fields of image processing and pattern recognition. The non-symmetry and anti-packing model (NAM) is a general pattern representation model that has been developed to help design some efficient image representation methods. In this paper, inspired by the idea of computing moments based on the S-Tree coding (STC) representation and by using the NAM and extended shading (NAMES) approach, we propose a fast algorithm for computing lower order moments based on the NAMES representation, which takes O(N) time where N is the number of NAM blocks. By taking three idiomatic standard gray images ‘Lena’, ‘F16’, and ‘Peppers’ in the field of image processing as typical test objects, and by comparing our proposed algorithm with the conventional algorithm and the popular STC representation algorithm for computing the lower order moments, the theoretical and experimental results presented in this paper show that the average execution time improvement ratios of the proposed NAMES approach over the STC approach, and also the conventional approach are 26.63%, and 82.57% respectively while maintaining the image quality.     

Some Kind of Analogtivity: anti-simulation through design

This paper discusses and explores issues surrounding current approaches to the design of technological products and offers two critical design proposals for presentation and debate. Primarily driven by contemporary theoretical writings and thoughts on the subject of ‘technology’ and ‘simulation’, currently being offered by leading thinkers on these subjects and expressed as ‘technological objects’; they are the result of a critical investigation into the emerging design issues surrounding ‘interaction’ and ‘transparency’. By using ‘popular’ language of product design as a vehicle, they exist as ‘cultural offerings’ exploring an alternative future for technological products not necessarily governed by science and economics.     

Reactive direction control for a mobile robot: a locust-like control of?escape direction emerges when a?bilateral pair of model locust visual neurons are integrated

Locusts possess a bilateral pair of uniquely identifiable visual neurons that respond vigorously to the image of an approaching object. These neurons are called the lobula giant movement detectors (LGMDs). The locust LGMDs have been extensively studied and this has lead to the development of an LGMD model for use as an artificial collision detector in robotic applications. To date, robots have been equipped with only a single, central artificial LGMD sensor, and this triggers a non-directional stop or rotation when a potentially colliding object is detected. Clearly, for a robot to behave autonomously, it must react differently to stimuli approaching from different directions. In this study, we implement a bilateral pair of LGMD models in Khepera robots equipped with normal and panoramic cameras. We integrate the responses of these LGMD models using methodologies inspired by research on escape direction control in cockroaches. Using ‘randomised winner-take-all’ or ‘steering wheel’ algorithms for LGMD model integration, the Khepera robots could escape an approaching threat in real time and with a similar distribution of escape directions as real locusts. We also found that by optimising these algorithms, we could use them to integrate the left and right DCMD responses of real jumping locusts offline and reproduce the actual escape directions that the locusts took in a particular trial. Our results significantly advance the development of an artificial collision detection and evasion system based on the locust LGMD by allowing it reactive control over robot behaviour. The success of this approach may also indicate some important areas to be pursued in future biological research.     

A comparison of dispatching rules and genetic algorithms for job shop schedules of standard hydraulic cylinders

Hydraulic cylinders perform straight-line reciprocating movements, and they have been used widely in various forms in many different industries. In this paper, we select a sample of the various types of standard hydraulic cylinders. Each cylinder’s near-optimal processing time and the processing order of the cylinder’s parts are investigated using two different techniques. First, we study typical procedures, known as ‘Dispatching Rules’, which would be used in a job shop to resolve scheduling problems. Second, we investigate another kind of technique, called ‘Genetic Algorithms’. The goal of this paper, we show that efficient scheduling solutions are calculated by using dispatching rules and genetic algorithms for manufacturing standard hydraulic cylinders, and we propose that a way to use dispatching rules in association with genetic algorithms should be considered for resolving job shop scheduling problems.     

Antisedentary Beigeless Computing

Conclusion Four decades of sporadic invention and experimentation of and with non-traditional human-computer interface schemes have congealed (somewhat abruptly though not without a few clear-sighted antecedents) into a new field of information system design, here calledAntisedentary Beigeless Computing, that consciously rejects the traditional conception of isolated tete-a-tete between the human and the box-CRT-keyboardmouse. ABC systems instead favour the complementary directions away from this notion of an immobile info-shrine: more personal, intimate, and portable information access; and more diffuse, environmentally-integrated information access. Consideration of ABC projects to date seems to suggest that no single instance can alone express the full generality required of a ‘working’ information system, so that (on the one hand) system design must acknowledge that a complex set of trade-offs involving capabilities, universality, specificity, personalization, and generality is inescapable; while (on the other hand) an ideal, eventual ‘information environment’ will inevitably comprise the careful interweaving of some number of individual ABC systems. Taxonomies and classification schema can rarely hope to be found complete or flawless before the collection of items that they purport to describe have themselves reached the evolutionary stasis of ‘adulthood’ — that is, there is typically some threshold of development or growth beyond which few enough surprises lurk that an encompassing taxonomy can be constructed and observed to reliably encompass, in the longer term. The domain of ABC thought is still quite nascent, and so we would be foolish to assume that all its extremities of form and connotation are now visible, but to the extent that we can already see the outlines of a ‘field’ it is reasonable to make a first run at an analytic taxonomy. The ‘independent character axes’ approach presented here seems broad and loose enough to accommodate any number of additions to the basic stable of ABC systems. It is, further, a taxonomy amenable to significant revision as may be found necessary: axes can be added, deleted, reconstrued, etc. as time and consideration clarify our understanding of ABC. However, it should also be anticipated that the field will eventually coalesce around a much smaller number of better-defined ‘axes’ and thus permit taxonomic reversion to the more hierarchical (and finally more satisfying) ‘Linnean’ scheme we'd originally imagined establishing.     

Frame rate as a QoS parameter and its influence on speech perception

The preservation of QoS for multimedia traffic through a data network is a difficult problem. We focus our attention on video frame rate and study its influence on speech perception. When sound and picture are discrepant (e.g., acoustic ‘ba’ combined with visual ‘ga’), subjects perceive a different sound (such as ‘da’). This phenomenon is known as the McGurk effect. In this paper, the influence of degraded video frame rate on speech perception is studied. It is shown that, when frame rate decreases, correct hearing is improved for discrepant stimuli and is degraded for congruent (voice and picture are the same) stimuli. Furthermore, we studied the case where lip closure was always captured by the synchronization of sampling time and lip position. In this case, frame rate has little effect on mishearing for congruent stimuli. For discrepant stimuli, mishearing is decreased with degraded frame rate. These results indicate that the stiff motion of lips resulting from low frame rate cannot give enough labial information for speech perception. In addition, the effect of delaying the picture to correct for low frame rate was studied. The results, however, were not as definitive as expected, because of compound effects related to the synchronization of sound and picture. Finally, we inspected the still pictures of normal Japanese speech and determined a lower limit of frame rate from the view point of assisting hearing.     

From human-centred to human-context centred approach: looking back over ‘the hills’, what has been gained and lost?

The cornerstone of the human-centred tradition lies in two notions: socially useful production and human machine symbiosis. However, only the latter became in focus in the successive user-centred design approaches. The paper makes a critical ‘flash-back’ to various human centred design approaches since the 1970s. In addition, it explores the sustainability challenges facing the current situation and suggests that ‘human-centredness’ should be extended to ‘human-context centred’ approach in order to recognize the challenges of the sustainability. Finally, the paper discuss the possibilities to develop and use narrative and modelling simulation methods including both qualitative and quantitative tools in a combined approach to meet the challenges of sustainable development within such a human-context centred approach.     

Visual Acuity in Day for Night

In film production, it is sometimes not convenient or directly impossible to shoot some night scenes at night. The film budget, schedule or location may not allow it. In these cases, the scenes are shot at daytime, and the ‘night look’ is achieved by placing a blue filter in front of the lens and under-exposing the film. This technique, that the American film industry has used for many decades, is called ‘Day for Night’ (or ‘American Night’ in Europe.) But the images thus obtained don’t usually look realistic: they tend to be too bluish, and the objects’ brightness seems unnatural for night-light. In this article we introduce a digital Day for Night algorithm that achieves very realistic results. We use a set of very simple equations, based on real physical data and visual perception experimental data. To simulate the loss of visual acuity we introduce a novel diffusion Partial Differential Equation (PDE) which takes luminance into account and respects contrast, produces no ringing, is stable, very easy to implement and fast. The user only provides the original day image and the desired level of darkness of the result. The whole process from original day image to final night image is implemented in a few seconds, computations being mostly local.     

Decision Making and Management of Dynamic Risk

Managing dynamic environments often requires decision making under uncertainty and risk. Two types of uncertainty are involved: uncertainty about the state and the evolution of the situation, and ‘openness’ of the possible actions to face possible consequences. In an experimental study on risk management in dynamic situations, two contrasted ‘ecological’ scenarios – transposed from effective situations of emergency management – were compared in order to identify the impact of their ‘openness’ in the subjects’ strategies for decision making. The ‘Lost Child’ scenario presented qualitative and irreversible consequences (child’s death) and high uncertainty; it exerted high demands both in risk assessment (risk representation) and action elaboration and choice. A less open situation (‘Hydrocarbon Fire’) required a main choice between two contrasted actions, with quantitative computable consequences. The strategies of ‘experimental subjects’ (university students) and ‘operative subjects’ (professional fire-fighter officers) were compared in order to evaluate the ecological validity of experimental research in this field, from the point of view of the subjects themselves. The two scenarios appeared to be independent, so that quite different models of decision making have to be hypothesised, differing by the importance of assessing risk and defining possible actions on the one hand, and by the process of choice on the other. ‘Experimental’ subjects dramatically differed from ‘operative’ subjects when confronted with the same scenario, particularly for the less technical but more demanding scenario. It is hypothesised that three components might account for the effect of the situations and for the differences between and within groups of subjects: importance of situation assessment, spatial abilities, and global orientation of activity in managing dynamic risk.