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The development of grasping is an important milestone that infants encounter during the first months of life. Novel approaches for measuring infants' manual actions are based on sensorized platform usable in natural settings, such as instrumented wireless toys that could be exploited for diagnosis and rehabilitation purposes. A new sensorized wireless toy has been designed and developed with embedded pressure sensors and audio-visual feedback. The fulfillment of clinical specifications has been proved through mechanical and electrical characterization. Infants showed a good grade of acceptance to such kind of tools, as confirmed by the results of preliminary tests that involved nine healthy infants: the dimensions fulfill infants' anthropometrics, the device is robust and safe, the acquired signals are in the expected range and the wireless communication is stable. Although achieved only through preliminary tests, such results confirm the hypothesis that this typology of instrumented toys could be useful for quantitative monitoring and measuring infants' motor development and ready to be evaluated for assessing motor skills through appropriate clinical trials.

Animals exploit soft structures to move effectively in complex natural environments. These capabilities have inspired robotic engineers to incorporate soft technologies into their designs. The goal is to endow robots with new, bioinspired capabilities that permit adaptive, flexible interactions with unpredictable environments. Here, we review emerging soft-bodied robotic systems, and in particular recent developments inspired by soft-bodied animals. Incorporating soft technologies can potentially reduce the mechanical and algorithmic complexity involved in robot design. Incorporating soft technologies will also expedite the evolution of robots that can safely interact with humans and natural environments. Finally, soft robotics technology can be combined with tissue engineering to create hybrid systems for medical applications., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Nowadays, respiratory syndrome represents the most common neonatal pathology. Nevertheless, being respiratory assistance in newborns a great challenge for neonatologists and nurses, use of simulation-based training is quickly becoming a valid meaning of clinical education for an optimal therapy outcome. Commercially available simulators, are, however, not able to represent complex breathing patterns and to evaluate specific alterations. The purpose of this work has been to develop a smart, lightweight, compliant system with variable rigidity able to replicate the anatomical behavior of the neonatal lung, with the final aim to integrate such system into an innovative mechatronic simulator device. A smart material based-system has been proposed and validated: Dielectric Electro Active Polymers (DEAP), coupled to a purposely shaped silicone camera, has been investigated as active element for a compliance change simulator able to replicate both physiological and pathological lung properties. Two different tests have been performed by using a bi-components camera (silicone shape coupled to PolyPower film) both as an isolated system and connected to an infant ventilator. By means of a pressure sensor held on the silicon structure, pressure values have been collected and compared for active and passive PolyPower working configuration. The obtained results confirm a slight pressure decrease in active configuration, that is in agreement with the film stiffness reduction under activation and demonstrates the real potentiality of DEAP for active volume changing of the proposed system.

Octopuses are molluscs that belong to the group Cephalopoda. They lack joints and rigid links, and as a result, their arms possess virtually limitless freedom of movement. These flexible appendages exhibit peculiar biomechanical features such as stiffness control, compliance, and high flexibility and dexterity. Studying the capabilities of the octopus arm is a complex task that presents a challenge for both biologists and roboticists, the latter of whom draw inspiration from the octopus in designing novel technologies within soft robotics. With this idea in mind, in this study, we used new, purposively developed methods of analysing the octopus arm in vivo to create new biologically inspired design concepts. Our measurements showed that the octopus arm can elongate by 70% in tandem with a 23% diameter reduction and exhibits an average pulling force of 40 N. The arm also exhibited a 20% mean shortening at a rate of 17.1 mm s(-1) and a longitudinal stiffening rate as high as 2 N (mm s)(-1). Using histology and ultrasounds, we investigated the functional morphology of the internal tissues, including the sinusoidal arrangement of the nerve cord and the local insertion points of the longitudinal and transverse muscle fibres. The resulting information was used to create novel design principles and specifications that can in turn be used in developing a new soft robotic arm.

Soft robotics is a current focus in robotics research because of the expected capability of soft robots to better interact with real-world environments. As a point of inspiration in the development of innovative technologies in soft robotics, octopuses are particularly interesting 'animal models'. Octopus arms have unique biomechanical capabilities that combine significant pliability with the ability to exert a great deal of force, because they lack rigid structures but can change and control their degree of stiffness. The octopus arm motor capability is a result of the peculiar arrangement of its muscles and the properties of its tissues. These special abilities have been investigated by the authors in a specific study dedicated to identifying the key principles underlying these biological functions and deriving engineering requirements for robotics solutions. This paper, which is the second in a two-part series, presents how the identified requirements can be used to create innovative technological solutions, such as soft materials, mechanisms and actuators. Experiments indicate the ability of these proposed solutions to ensure the same performance as in the biological model in terms of compliance, elongation and force. These results represent useful and relevant components of innovative soft-robotic systems and suggest their potential use to create a new generation of highly dexterous, soft-bodied robots.

Control and modelling of continuum robots are challenging tasks for robotic researchers. Most works on modelling are limited to piecewise constant curvature. In many cases they neglect to model the actuators or avoid a continuum approach. In particular, in the latter case this leads to a complex model hardly implemented. In this work, a geometrically exact steady-state model of a tendon-driven manipulator inspired by the octopus arm is presented. It takes a continuum approach, fast enough to be implemented in the control law, and includes a model of the actuation system. The model was experimentally validated and the results are reported. In conclusion, the model presented can be used as a tool for mechanical design of continuum tendon-driven manipulators, for planning control strategies or as internal model in an embedded system.

Learning to grasp an object is an important milestone in neurological development during infancy. Several studies report development of reaching in infants but less attention is devoted to reaching with successful grasping and to development of grip force. This study investigates, in the first weeks of life, the development of palmar grasp both for assessment of unimanual/bimanual grasping actions in centrally and laterally placed objects and for measurement of exerted power grip force. We longitudinally examined ten infants from 18 weeks to 41 weeks, at 2-weeks intervals, with a toy placed in three positions (body midline, ipsilateral and contralateral shoulder). Our main aim was to study this development through an ecological approach. This was possible thanks to the use of the "biomechatronic gym", a new platform purposively developed for measuring reaching and grasping forces. These longitudinal trials showed a good level of acceptance and involvement by infants of the entire system. The results demonstrated a significant increase in unimanual power grip force between the 18th and 30th week followed by a flat period until the 41st week; we also ascertained an early tendency to play bimanually with centrally and laterally placed objects with a subsequent increase in all ages of unimanual successful power grasping both for central task and midline crossing. These developmental changes may be, in part, related to organism constraints such as maturation of the corticospinal tract., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Octopus arms are extremely dexterous structures. The special arrangements of the muscle fibers and nerve cord allow a rich variety of complex and fine movements under neural control. Historically, the arm structure has been investigated using traditional comparative morphological ex vivo analysis. Here, we employed ultrasound imaging, for the first time, to explore in vivo the arms of the cephalopod mollusc Octopus vulgaris. Sonographic examination (linear transducer, 18 MHz) was carried out in anesthetized animals along the three anatomical planes: transverse, sagittal and horizontal. Images of the arm were comparable to the corresponding histological sections. We were able, in a non-invasive way, to measure the dimensions of the arm and its internal structures such as muscle bundles and neural components. In addition, we evaluated echo intensity signals as an expression of the difference in the muscular organization of the tissues examined (i.e. transverse versus longitudinal muscles), finding different reflectivity based on different arrangements of fibers and their intimate relationship with other tissues. In contrast to classical preparative procedures, ultrasound imaging can provide rapid, destruction-free access to morphological data from numerous specimens, thus extending the range of techniques available for comparative studies of invertebrate morphology.

Soft robotics is a challenging and promising branch of robotics. It can drive significant improvements across various fields of traditional robotics, and contribute solutions to basic problems such as locomotion and manipulation in unstructured environments. A challenging task for soft robotics is to build and control soft robots able to exert effective forces. In recent years, biology has inspired several solutions to such complex problems. This study aims at investigating the smart solution that the Octopus vulgaris adopts to perform a crawling movement, with the same limbs used for grasping and manipulation. An ad hoc robot was designed and built taking as a reference a biological hypothesis on crawling. A silicone arm with cables embedded to replicate the functionality of the arm muscles of the octopus was built. This novel arm is capable of pushing-based locomotion and object grasping, mimicking the movements that octopuses adopt when crawling. The results support the biological observations and clearly show a suitable way to build a more complex soft robot that, with minimum control, can perform diverse tasks.

We designed an fMRI experiment comparing perception of human faces and robotic faces producing emotional expressions. The purpose of our experiment was to investigate engagement of different parts of the social brain by viewing these animate and inanimate agents. Both human and robotic face expressions evoked activity in face-responsive regions in the fusiform gyrus and STS and in the putative human mirror neuron system. These results suggest that these areas mediate perception of agency, independently of whether the agents are living or not. By contrast, the human faces evoked stronger activity than did robotic faces in the medial pFC and the anterior temporal cortex--areas associated with the representation of others' mental states (theory of mind), whereas robotic faces evoked stronger activity in areas associated with perception of objects and mechanical movements. Our data demonstrate that the representation of the distinction between animate and inanimate agents involves areas that participate in attribution of mental stance.

Currently the study of infants grasping development is purely clinical, based on functional scales or on the observation of the infant while playing; no quantitative variables are measured or known for diagnosis of eventually disturbed development. The aim of this work is to show the results of a longitudinal study achieved by using a "baby gym" composed by a set of instrumented toys, as a tool to measure and stimulate grasping actions, in infants from 4 to 9 months of life. The study has been carried out with 7 healthy infants and it was observed, during infants development, an increase of precision grasp and a reduction of power grasp with age. Moreover the forces applied for performing both precision and power grasp increase with age. The proposed devices represent a valid tool for continuous and quantitative measuring infants manual function and motor development, without being distressful for the infant and consequently it could be suitable for early intervention training during the first year of life. The same system, in fact, could be used with infants at high risk for developmental motor disorder in order to evaluate any potential difference from control healthy infants.

The aim of this study was to understand and measure the lower limbs muscular activation patterns both in healthy and spinal cord injured (SCI) subjects during robot-assisted locomotor exercise. Electromyographic (EMG) activity of four leg's muscles (rectus and biceps femoris, tibialis anterioris and gastrocnemius) was recorded and analyzed at two different percentages of body weight support, three stepping velocities and three different modalities. SCI subjects were recorded also after four weeks training to evaluate the effectiveness of lower limb robot-assisted rehabilitative treatment. A multi-factor ANOVA on the integrated muscle activity (IEMG) parameters both in healthy and SCI subjects was performed. Higher muscular activities both in healthy subjects and SCI patients were found during the exercises using the "DGO active" modality and higher stepping velocities. A significant increased bilateral muscular activity was observed in each SCI subject after the rehabilitation treatment. The method proposed to analyze EMG data provides a quantitative description of the lower limb muscular recruitment and can contribute to identify the optimal rehabilitation treatment's conditions., (© 2011 IEEE)

Our vision of plants is changing dramatically: from insensitive and static objects to complex living beings able to sense the environment and to use the information collected to adapt their behaviour. At all times humans imitate ideas and concepts from nature to resolve technological problems. Solutions coming from plants have the potential to face challenges and difficulties of modern engineering design. Characteristic concepts of the plant world such as reiteration, modularity and swarm behaviour could be of great help resolving technological problems. On the other hand a biorobotic approach would facilitate the resolution of many biological problems. In this paper, the concept of a plant-inspired robot is proposed for the investigation of both biological and technological issues.

Anticipation of sensory consequences of actions is critical for the predictive control of movement that explains most of our sensory-motor behaviors. Plenty of neuroscientific studies in humans suggest evidence of anticipatory mechanisms based on internal models. Several robotic implementations of predictive behaviors have been inspired on those biological mechanisms in order to achieve adaptive agents. This paper provides an overview of such neuroscientific and robotic evidences; a high-level architecture of sensory-motor coordination based on anticipatory visual perception and internal models is then introduced; and finally, the paper concludes by discussing the relevance of the proposed architecture within the context of current research in humanoid robotics.

The study and measurement of grasping actions and forces in humans is important in a variety of contexts. In infants, it can give insights on the typical and atypical motor development, while it poses functional and operative requirements that are not fully matched by current sensing technology. Novel approaches for measuring infants' grasping actions are based on sensorized platform usable in natural settings. A new set of instrumented toys has been designed for the assessment/stimulation of upper limbs of infants between 4 and 9 months. A purposive biomechatronic gym has been developed by integrating pressure and force sensors and visual/auditory stimulations to the usual gym structure and hanging toys (cow, flower and ring puppets), so that the infants' actions on the gym can be monitored, measured and stimulated. With the developed system, a longitudinal clinical validation has been carried out with seven healthy infants. From data analysis it is possible to identify a trend in manual forces development and this result confirms the usefulness of the system proposed as a clinical tool for monitoring infants' grasping development.

This paper reports the rationale and design of a robotic arm, as inspired by an octopus arm. The octopus arm shows peculiar features, such as the ability to bend in all directions, to produce fast elongations, and to vary its stiffness. The octopus achieves these unique motor skills, thanks to its peculiar muscular structure, named muscular hydrostat. Different muscles arranged on orthogonal planes generate an antagonistic action on each other in the muscular hydrostat, which does not change its volume during muscle contractions, and allow bending and elongation of the arm and stiffness variation. By drawing inspiration from natural skills of octopus, and by analysing the geometry and mechanics of the muscular structure of its arm, we propose the design of a robot arm consisting of an artificial muscular hydrostat structure, which is completely soft and compliant, but also able to stiffen. In this paper, we discuss the design criteria of the robotic arm and how this design and the special arrangement of its muscular structure may bring the building of a robotic arm into being, by showing the results obtained by mathematical models and prototypical mock-ups.

The capability of grasping and lifting an object in a suitable, stable and controlled way is an outstanding feature for a robot, and thus far, one of the major problems to be solved in robotics. No robotic tools able to perform an advanced control of the grasp as, for instance, the human hand does, have been demonstrated to date. Due to its capital importance in science and in many applications, namely from biomedics to manufacturing, the issue has been matter of deep scientific investigations in both the field of neurophysiology and robotics. While the former is contributing with a profound understanding of the dynamics of real-time control of the slippage and grasp force in the human hand, the latter tries more and more to reproduce, or take inspiration by, the nature's approach, by means of hardware and software technology. On this regard, one of the major constraints robotics has to overcome is the real-time processing of a large amounts of data generated by the tactile sensors while grasping, which poses serious problems to the available computational power. In this paper a bio-inspired approach to tactile data processing has been followed in order to design and test a hardware-software robotic architecture that works on the parallel processing of a large amount of tactile sensing signals. The working principle of the architecture bases on the cellular nonlinear/neural network (CNN) paradigm, while using both hand shape and spatial-temporal features obtained from an array of microfabricated force sensors, in order to control the sensory-motor coordination of the robotic system. Prototypical grasping tasks were selected to measure the system performances applied to a computer-interfaced robotic hand. Successful grasps of several objects, completely unknown to the robot, e.g. soft and deformable objects like plastic bottles, soft balls, and Japanese tofu, have been demonstrated.

This paper presents the design and development of a novel biomimetic quadruped robot for behavior studies of rats and mice. Many studies have been performed using these animals for the purpose of understanding human mind in psychology, pharmacology and brain science. In these fields, several experiments on social interactions have been performed using rats as basic studies of mental disorders or social learning. However, some researchers mention that the experiments on social interactions using animals are poorly-reproducible. Therefore, we consider that reproducibility of these experiments can be improved by using a robotic agent that interacts with an animal subject. Thus, we developed a small quadruped robot WR-2 (Waseda Rat No. 2) that behaves like a real rat. Proportion and DOF arrangement of WR-2 are designed based on those of a mature rat. This robot has four 3-DOF legs, a 2-DOF waist and a 1-DOF neck. A microcontroller and a wireless communication module are implemented on it. A battery is also implemented. Thus, it can walk, rear by limbs and groom its body.

This work illustrates new tools and methods for an in vivo and direct, but non-invasive, measurement of an octopus arm mechanical properties. The active elongation (longitudinal stretch) and the pulling force capability are measured on a specimen of Octopus vulgaris in order to quantitatively characterize the parameters describing the arm mechanics, for biomimetic design purposes. The novel approach consists of observing and measuring a living octopus with minimally invasive methods, which allow the animal to move with its complete ability. All tools are conceived in order to create a collaborative interaction with the animal for the acquisition of active measures. The data analysis is executed taking into account the presence of an intrinsic error due to the mobility of the subject and the aquatic environment. Using a system of two synchronized high-speed high-resolution cameras and purpose-made instruments, the maximum elongation of an arm and its rest length (when all muscles fibres are relaxed during propulsion movement) are measured and compared to define the longitudinal stretch, with the impressive average result of 194%. With a similar setup integrated with a force sensor, the pulling force capability is measured as a function of grasp point position along the arm. The measured parameters are used as real specifications for the design of an octopus-like arm with a biomimetic approach.

In this work, a novel technological approach to the early diagnosis of neuro-developmental disorders is presented. Disorders such as Autism are typically diagnosed after language development, i.e. after the 2-3 years of age. In this paper, three different typologies of instruments are presented which are designed to assess infants behavior in different perceptual and motor domains. The first is an instrumented toy embedding kinematic and force sensors for studying grasping and manipulation in infants as young as 6 months old. The second is a wearable device for sensing the kinematics of the upper and lower limbs of infants, designed to assess spontaneous movements in premature babies. The third is a multimodal audio-visuo-vestibular cap which was designed to assess infants orienting behaviors in social situations in response to audio and visual stimuli.

This paper presents a biomechanical model of the sensorial cells in otolithic organs and a design of a 3D device that imitates the biological system. Starting from anatomical and physiological data, mechanical and structural parameters have been identified and a mechanical model has been formulated, by considering the cilia and kinocilium as a interconnected structure. The mechanical model was used to simulate the behavior of the system under known conditions. Furthermore, the behavior of a proximal link to the kinocilium were investigated for a better comprehension regarding the polymeric materials that could be used to model and manufacture the biological organs. The results obtained from the models were used to design a biomimetic organ.

The present paper aims at understanding the biomechanics of an octopus tentacle as preliminary work for designing and developing a new robotic octopus tentacle. The biomechanical characterization of the biological material has been carried out on samples of Octopus vulgaris tentacles with engineering methods and tools, i.e. by biomechanical measurements of the tentacle elasticity and tension-compression stress/stretch curves. Another part of the activities has been devoted to the study of materials that can reproduce the viscoelastic behavior of the tentacle. The work presented here is part of the ongoing study and analysis on new design principles for actuation, sensing, and manipulation control, for robots with increased performance, in terms of dexterity, control, flexibility, applicability.

This paper presents a biomechanical model of the semicircular canals of the human vestibular system and the design of a 3D biomimetic structure that mimics the biological system. Starting from anatomical and physiological data, mechanical and structural parameters have been identified and a mathematical model has been formulated, by considering the semicircular organ as a canal filled by a liquid. The mathematical and mechanical models were used to simulate the behavior of the semicircular canals under known conditions of angular velocity and acceleration along three axes. Furthermore, the membrane inside the semicircular canals was simulated to understand what the mechanical properties of the membrane are and if polymeric materials can reproduce the mechanical characteristics of the biological organ. The results obtained from the model allow to design a biomimetic organ, as a part of a biomimetic vestibular system, by following this biomechatronic approach.