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Inspired by common patterns of biological movement, a series of near-infrared (NIR) laser-driven bionic intelligent hydrogel actuators were successfully fabricated via the combination of infiltration method (entirety infiltration and locality infiltration), structure design and material characteristics. The controllable distribution of graphene oxide (GO) particles in a hydrogel matrix resulting from the infiltration method led to abundant bionic deformations with multiple degrees of freedom and flexibility. In addition to the highest response speed of 187.7°/s, the hydrogel actuators underwent accurate and repeatable static deformations and efficient and stabilized dynamic locomotion, demonstrated, for example, through the assembly of origami, the deformation of fingers and palm, the closing and blooming of a chrysanthemum and the crawling of an inchworm. This study opens a new path for practical bionic applications of NIR-triggered hydrogel actuators in self-assembly biosensor, targeted drug delivery and minimally invasive surgery.

Developing robotic manipulators capable of performing effective physical interaction tasks is a challenging topic. In this study, we design a soft robotic arm (SRA) with multiple degrees of freedom inspired by the flexible structures and the unique motion mechanism of the octopus arm. The SRA is fabricated with elastomeric materials, which consists of four series of integrated pneumatic chambers that play similar roles as the muscles in the octopus arm can achieve large bending in various directions with variable stiffness. This SRA displays specified movements via controlling pressure and selecting channels. Moreover, utilizing parallel control, the SRA demonstrates complicated three-dimensional motions. The force response and motion of the SRA are determined both experimentally and computationally. The applications of the present SRA include tightly coiling around the objects because of its large bending deformation (nearly $$360^{{\circ }})$$ , grasping multiple objects, and adjusting the grabbing mode in accordance with the shape of objects.

Origami, also known as paper folding, has shown its potential to construct 3D structures from designed crease patterns on a flat sheet. This paper proposes a method to design axisymmetric 3D origami with generic six-crease bases. Inspired by the conventional six-crease bases, i.e., waterbomb base or Yoshimura base, where six regular crease lines meet at an interior vertex, we generalize the generic base so that the lengths of the crease lines can be regular or irregular. This method is based on designing the crease patterns. First, we interactively generate a crease pattern consisting of such generic bases. Then, our method analytically calculates the 3D origami shape with an axisymmetric structure. We demonstrate various configurations, i.e., sets of input parameters, to explore the variations of the calculated 3D origami. The 3D origami can have multiple degrees of freedom, but by continually changing one parameter we present a motion that can axisymmetrically deploy or flatten the shape. The method for designing 3D origami has potential applications ranging from self-folding tessellations to deployable architectures.

Vibration vehicle models provide a great opportunity to integrate vehicle-based vibrations into a mechanical engineering vibrations course. This paper documents and discusses an approach to a multiple-degree-of-freedom (MDOF) in regards to pitch and bounce of the vehicle body with dampening and stiffness observed. The approach utilizes hand calculations, OCTAVE, and ANSYS to solve speed-bump induced vibration and to calculate vibrations modes. The problem involves a bicycle-model approach to a vehicle’s response when subject to a speed bump, or a sudden impulse load upon the forward-face of the model. These responses are captured and analyzed on pitch and bounce of the model at the center-of-gravity and the front/rear sides of the model. Graphical models capture responses of the loading conditions and the modal equations of the model providing a method of studying and understanding vibrational responses under provided stiffness. Using ANSYS as an approach of the model to capture damping response, further graphical models can be captured and used to describe motions of the vehicle model’s center-of-gravity, frontward and rearward wheel assembly, and the pitch (rotation) of the center-of-gravity to the introduced responses. A successful study with analysis of each graphical element and further dissemination of the results is concluded.

With the evolution of technology, it is now possible to build more flexible surgical instruments with multiple degrees of freedom that can be deployed in natural orifice translumenal endoscopic surgery, further reducing tissue damage, blood loss, and recovery time. However, the limits of flexible robots are mainly represented by the lack of accurate position feedback during the surgical procedure. The most critical problems of shape sensors are size and quantity limits, as well as sterilizability. This paper presents a novel helical configuration of single optic fiber with multiple fiber Bragg grating sensors to measure the shape of flexible robots. Detailed design of helix parameters, simulation and verification experiments were performed. We have shown the feasibility of helical configuration to reduce the effect of temperature, and detect the torsion and bending of the flexible shaft. The experimental results demonstrated the potential to provide a shape detection for flexible robot.

A multivariable approach of modeling and feedforward control of rate-independent hysteresis in multi-dof piezoelectric actuators is proposed in this paper. For that, the classical Prandtl–Ishlinskii (CPI) hysteresis model is extended into multivariable. Then, based on the inverse multiplicative structure and on the multivariable CPI model, a compensator is suggested. The proposed compensator does not require an extra-calculation: As soon as the model is identified, the compensator is obtained by structure. Furthermore, inversion of the model is avoided. Additionally to the hysteresis suppression, the multivariable compensator permits to reduce the cross-couplings between the axes which is not possible with standard techniques. The modeling and the inversion-free compensator are afterward applied to a two-degrees-of-freedom (2-dof) piezoactuator. The extensive investigated experimental tests demonstrate that the strong cross-couplings and the strong hysteresis in the two axes can be substantially reduced and linearized, respectively.

Humans perform a variety of feedback adjustments to maintain balance during walking. These include lateral footfall placement, and center of pressure adjustment under the stance foot, to stabilize lateral balance. A less appreciated possibility would be to steer for balance like a bicycle, whose front wheel may be turned toward the direction of a lean to capture the center of mass. Humans could potentially combine steering with other strategies to distribute balance adjustments across multiple degrees of freedom. We tested whether human balance can theoretically benefit from steering, and experimentally tested for evidence of steering for balance. We first developed a simple dynamic walking model, which shows that bipedal walking may indeed be stabilized through steering—externally rotating the foot about vertical toward the direction of lateral lean for each footfall—governed by linear feedback control. Moreover, least effort (mean-square control torque) is required if steering is combined with lateral foot placement. If humans use such control, footfall variability should show a statistical coupling between external rotation with lateral placement. We therefore examined the spontaneous fluctuations of hundreds of strides of normal overground walking in healthy adults (N = 26). We found significant coupling (P = 9·10−8), of 0.54 rad of external rotation per meter of lateral foot deviation. Successive footfalls showed a weaker, negative correlation with each other, similar to how a bicycle’s steering adjustment made for balance must be followed by gradual corrections to resume the original travel direction. Steering may be one of multiple strategies to stabilize balance during walking.

Restoration of intestinal continuity following total proctocolectomy is performed by constructing an ileal pouch-anal anastomosis (IPAA). Since the advent of this technique in 1978, the operation has evolved from hand-sewn to stapled anastomoses, from a two-stage to three-stage approach in the setting of immunosuppression, and from an open technique to a minimally invasive approach. While laparoscopy has become widely used for IPAA construction, a robotic approach may offer several advantages and may become more widely used in future years. The bony confines of a narrow pelvis make the angles of laparoscopy challenging, and the robot provides improved three-dimensional and high-definition visualization of the pelvis. Once the pelvic floor has been exposed, the improved visualization and multiple degrees of freedom help to improve deployment of intracorporeal stapling devices. Herein, we discuss our approach to a robotic IPAA and highlight steps that may require intraoperative troubleshooting.

The foot is a complex system with multiple degrees of freedom that play an essential role in running or sprinting. The intrinsic foot muscles (IFM) are the main local stabilizers of the foot and are part of the active and neural subsystems that constitute the foot core. These muscles lengthen eccentrically during the stance phase of running before shortening at the propulsion phase, as the arch recoils in parallel to the plantar fascia. They play a key role in supporting the medial longitudinal arch, providing flexibility, stability and shock absorption to the foot, whilst partially controlling pronation. Much of the foot rigidity in late stance has been attributed to the windlass mechanism - the dorsiflexion of the toes building tension up in the plantar aponeurosis and stiffening the foot. In addition, recent studies have shown that the IFM provide a necessary active contribution in late stance, in order to develop sufficient impedance in the metatarsal-phalangeal joints. This in turn facilitates the propulsive forces at push-off. These factors support the critical role of the foot in providing rigidity and an efficient lever at push-off. During running or sprinting, athletes need to generate and maintain the highest (linear) running velocity during a single effort in a sprinting lane. Acceleration and sprinting performance requires forces to be transmitted efficiently to the ground. It may be of particular interest to strengthen foot muscles to maintain and improve an optimal capacity to generate and absorb these forces. The current evidence supports multiple exercises to achieve higher strength in the foot, such as the "short foot exercise," doming, toes curl, towing exercises or the more dynamic hopping exercises, or even barefoot running. Their real impact on foot muscle strength remains unclear and data related to its assessment remains scarce, despite a recognized need for this, especially before and after a strengthening intervention. It would be optimal to be able to assess it. In this article, we aim to provide the track and field community with an updated review on the current modalities available for foot strength assessment and training. We present recommendations for the incorporation of foot muscles training for performance and injury prevention in track and field.

Prosthetics need to incorporate the users sense of proprioception into the control paradigm to provide intuitive control, and reduce training times and prosthetic rejection rates. In the absence of functional tasks with a prosthetic, virtual cursor control tasks have been used to train users to control multiple degrees of freedom. In this study, A proportional position signal was derived from the cross-sectional ultrasound images of the users forearm. We designed a virtual cursor control task with one degree of freedom to measure the users ability to repeatably and accurately acquire different levels of muscle flexion, using only their sense of proprioception. The experiment involved a target acquisition task, where the cursors height corresponded to the extent of muscle flexion. Users were asked to acquire targets on a screen. Visual feedback was disabled at certain times during the experiment, to isolate the effect of proprioception. We found that as visual feedback was taken away from the subjects, position error increased but their stability error did not change significantly. This indicates that users are not perfect at using only their proprioceptive sense to reacquire a level of muscle flexion, in the absence of haptic or visual feedback. However, they are adept at retaining an acquired flexion level without drifting. These results could help to quantify the role of proprioception in target acquisition tasks, in the absence of haptic or visual feedback.

Stimulus distribution on a finger pad dynamically changes during dynamic interactions such as manipulation or handling of an object. This is caused by the magnitude and direction of the applied force on the finger pad and the elasticity of materials handled. Several past studies proposed wearable tactile systems. However, generation of distributed stimuli on a finger pad (multiple degrees of freedom stimulation) has not yet been achieved. Herein, we propose a rendering system for stimulus distribution on a finger pad. The proposed system consists of a display using multi-channel suction that presents distributed stimuli to a finger pad skin, and a real-time simulator that calculates dynamic pressure distribution on the finger pad when in contact with an elastic object. The developed display has good wearability as lightweight (5 g) and compact because it does not have an actuator on the fingertip in spite of multiple outputs (16 suction ports). We performed two different experiments using the proposed system. These experiments proved that it is possible to present different stimulus distribution depending on the contact posture between a finger and an object (experiment 1) and to present the softness of the virtual material with different elasticity values (experiment 2).

To reduce the torsional vibration of vehicle power transmission system (VPTS), a torsional vibration model with multiple degrees of freedom (MDOF) of VPTS was established. The scheme of equipping torsional vibration dampers (TVDs) on the drive shaft was employed by the calculation of the forced vibration and the free vibration of the VPTS. The energy method was used to optimize the parameters of single-stage, two-stage parallel, and two-stage series TVDs based on the principle that balances the damping effect and lightweight design. On the basis of this, the parameters of the models incorporating TVD and elastic couplings (ECs) were optimized. Results showed that the proposed method can ensure the damping effects of TVD and realize the lightweight.

The main drawback of the commercially available myoelectric hand prostheses is the absence of somatosensory feedback. We recently developed a feedback interface for multiple degrees of freedom myoelectric prosthesis that allows proprioceptive and sensory information (i.e., grasping force) to be transmitted to the wearer instantaneously. High information bandwidth is achieved through intelligent control of spatiotemporal distribution of electrical pulses over a custom-designed electrode array. As electrotactile sensations are location-dependent and the developed interface requires that electrical stimuli are perceived to be of the same intensity on all locations, a calibration procedure is of high importance. The aim of this study was to gain more insight into the calibration procedure and optimize this process by leveraging a priori knowledge. For this purpose, we conducted a study with 9 able-bodied subjects performing 10 sessions of the array electrode calibration. Based on the collected data, we optimized and simplified the calibration procedure by adapting the initial (baseline) amplitude values in the calibration algorithm. The results suggest there is an individual pattern of stimulation amplitudes across 16 electrode pads for each subject, which is not affected by the initial amplitudes. Moreover, the number of user actions performed and the time needed for the calibration procedure are significantly reduced by the proposed methodology. The research was supported by Tecnalia Research & Innovation, Spain, and the Ministry of Education, Science and Technological Development of Republic of Serbia (Project no. 175016). The authors would like to thank all the volunteers who participated in this study.

Restoration of intestinal continuity following total proctocolectomy is performed by constructing an ileal pouch-anal anastomosis (IPAA). Since the advent of this technique in 1978, the operation has evolved from hand-sewn to stapled anastomoses, a two-stage to three-stage approach in the setting of immunosuppression, and from an open technique to a minimally invasive approach. While laparoscopy has become widely used for IPAA construction, a robotic approach may offer several advantages and may become more widely used in the future years. The bony confines of a narrow pelvis make the angles of laparoscopy challenging, and the robot provides improved three-dimensional and high-definition visualization of the pelvis. Once the pelvic floor has been exposed, the better visualization and multiple degrees of freedom help to improve deployment of intracorporeal stapling devices. We will herein discuss our approach to a robotic IPAA and highlight steps that may require intraoperative troubleshooting.

Continuum robots have attracted increasing attention from robotic community due to their intrinsic compliance and high dexterity. However, the compliant body structures and multiple degrees of freedom (DOFs) make it difficult for operators to intuitively regulate the configuration of continuum robots. Therefore, this paper presents a rod-driven continuum robot with teleoperation device achieving master-slave control. The master articulated manipulator has the same number of joints as the slave continuum robot. The slave continuum robot is equipped with two continuum joints with elastic backbones. Each joint possesses two DOFs and is driven by three elastic rods. The configuration parameters of the master manipulator are acquired by embedded sensors and return to a host computer. After kinematics calculating, the control command is sent to the slave continuum robot, to reproduce the configuration of the master manipulator. Experimental results show that the robotic system can achieve good master-slave following performance.

CGH Interferometry provides the standard for accurate measurement of transmitted wavefront for large lenses. With multiple patterns on the same substrate, a CGH also enables simultaneous measurements of multiple degrees of freedom used for alignment.

End-effector tools with low weight, multiple degrees of freedom have significant application significance. At present, motor-driven robot operating tools generally have more complicated transmission systems as well as actuators, and the weight is also heavy. In this paper, a bolt-screwing tool based on a pneumatic slip ring structure is designed, which can realize two-DOF motion of clamping-releasing and rotating. The tool consists of a pneumatic slip ring with sealed structure and a cylinder driven gripper. This article also introduces the control strategy required to screw the bolt, and describes the configuration of the experiment. Finally, the bolt is screwed into the thread hole in the experiment to verify the reliability of the screw assembly tool and the effectiveness of the corresponding control scheme.

The quest to develop dexterous artificial arm which supports multiple degrees of freedom for amputees has attracted a lot of study interest in the last few decades. The outcome of some of the studies had identified surface Electromyography (EMG) as the most commonly used biological signal in predicting the motion intention of an amputee. Different EMG based control methods for multifunctional prosthesis have been proposed and investigated in a number of previous studies. However, no any multifunctional prostheses are clinically available yet. One of the possible reasons would be that the residual muscles after amputations might not produce sufficient EMG signals for movement classifications. In this study, we proposed to use electroencephalography (EEG) signals recorded from the scalp of an amputee as additional signals for motion identifications. The performance of a hybrid scheme based on the combination of EMG and EEG signals in identifying different hand and wrist movements was evaluated in one transhumeral amputee. Our pilot results showed that the proposed hybrid method increased the classification accuracy in identifying different hand and wrist movements of the amputee. This suggests that the proposed method may have potential to improve the control of multifunctional prostheses.

In this paper, a morphing carbon fibre composite aerofoil concept with an active trailing edge is proposed. This aerofoil features of camber morphing with multiple degrees of freedom. The shape morphing is enabled by an innovative structure driven by an electrical actuation system that uses linear ultrasonic motors (LUSM) with compliant runners, enabling full control of multiple degrees of freedom. The compliant runners also serve as structural components that carry the aerodynamic load and maintain a smooth skin curvature. The morphing structure with compliant truss is shown to exhibit a satisfactory flexibility and loading capacity in both numerical simulations and static loading tests. This design is capable of providing a pitching moment control independent of lift and higher L/D ratios within a wider angle-of-attack range. Such multiple morphing configurations could expand the flight envelope of future unmanned aerial vehicles. A small prototype is built to illustrate the concept, but as no off-the-shelf LUSMs can be integrated into this benchtop model, two servos are employed as actuators, providing two controlled degrees of freedom. This paper received a Written Paper Prize - Bronze Award from the Royal Aeronautical Society in 2018.

Reconfigurable devices, whose shape can be drastically altered, are central to expandable shelters, deployable space structures, reversible encapsulation systems and medical tools and robots. All these applications require structures whose shape can be actively controlled, both for deployment and to conform to the surrounding environment. While most current reconfigurable designs are application specific, here we present a mechanical metamaterial with tunable shape, volume and stiffness. Our approach exploits a simple modular origami-like design consisting of rigid faces and hinges, which are connected to form a periodic structure consisting of extruded cubes. We show both analytically and experimentally that the transformable metamaterial has three degrees of freedom, which can be actively deformed into numerous specific shapes through embedded actuation. The proposed metamaterial can be used to realize transformable structures with arbitrary architectures, highlighting a robust strategy for the design of reconfigurable devices over a wide range of length scales., Typically, most structures and devices that can be reconfigured are designed with application specific requirements. Inspired by modular origami ideas, Overvelde et al. present a mechanical metamaterial enabling the design of three-dimensional structures of arbitrary architecture with tunable shape, volume and stiffness.

Vertical oscillations of three loads of different masses connected by nonlinear viscoelastic springs (suspensions) are considered in the paper. An account for rheological properties of the suspension, an integral model with the Koltunov-Rzhanitsyn relaxation kernel is used. Effective computational algorithms have been developed for solving problems based on the use of quadrature formulas. The effect of rheological properties of suspension on the mass displacement from the position of static equilibrium is investigated as well as the influence of nonlinear properties of the suspension on the mode of vibration and frequency.

If a picture tells a thousand words, then we might ask ourselves how many photons does it take to form a picture? In terms of the transmission of the picture information, then the multiple degrees of freedom (e.g., wavelength, polarization, and spatial mode) of the photon mean that high amounts of information can be encoded such that the many pixel values of an image can, in principle, be communicated by a single photon. However, the number of photons required to transmit the image information is not necessarily, at least technically, the same as the number of photons required to image an object. Therefore, another equally important question is how many photons does it take to measure an unknown image?

The fascinating point of 2D and layered materials is that they can be assembled into van der Waals (vdW) heterostructures, in which atomic layers are integrated by vdW force. There are almost infinite potential combinations in vdW heterostructures owing to the multiple degrees of freedom, i.e., the choice of materials, stacking order, and lateral orientation angle at the interfaces. In this article, we review the fabrication technique of vdW heterostructures, which has played an essential role in the development of the 2D materials research field. First, we describe the primary technique of mechanical exfoliation to fabricate and identify high-quality atomic layers. We then discuss the assembly of atomic layers into vdW heterostructures. Finally, we introduce the recent advancement of fabrication techniques using autonomous robotic assembly. We hope this article would help the readers to acquire basic knowledge of vdW assembly and motivate them to fabricate vdW heterostructures.

International audience; Recent technological advancements in augmented and mixed reality devices opened up many opportunities to users to interact in their environments. However, there are many unanswered questions about the definition of these interaction paradigms. In this article, we present a new approach to interact in these environments: using the body as a physical support to constrain the movement of a multiple degrees of freedom device (3D Mouse). This mouse offers enough degrees of freedom as well as a necessary accuracy to support the interaction. The use of the body as a support for the interaction allows the user to move in his environment and avoids the inherent fatigue of mid-air interactions. Thus, we propose a new design space for tangible interactions on the body, and specifically on theforearm. To validate the feasibility of such an approach, we present an experiment aimed at establishing the range, stability and comfort of gestures performed with a multiple degrees of freedom mouse on the forearm.; Les récents avènements technologiques au travers des périphériques de réalité augmenté ou mixte ouvrent de nombreuses opportunités aux utilisateurs pour interagir dans leurs environnements. Cependant, il reste de nombreuses questions sur la définition de ces paradigmes d’interaction. Dans cet article, nous présentons une nouvelle approche avec l’utilisation du corps comme support physique pour contraindre les déplacements d’un périphérique de type souris 3D. Cette souris offre suffisamment de degrés de liberté et une précision satisfaisante pour supporter l’interaction. L’utilisation du corps comme support à l’interaction permet à l’utilisateur de se déplacer dans son environnement et réduit la fatigue inhérente à l’interaction en l’air. Ainsi, nous proposons un nouvel espace de conception pour les interactions tangibles sur le corps, et en particulier sur l’avant-bras. Pour valider la faisabilité d’une telle approche, nous présentons une expérience visant à établir la portée, stabilité et confort des gestes effectués avec une souris 3D sur l’avant-bras.

Optical information security techniques are developed at a fast pace over the past two decades. In the present scenario, where enormous amount of data is being exchanged, information security plays an important role in protecting the information/data from unauthorized use/access. In this context, securing information using optical means has become relevant, given the suitable features of speed and multiple degrees of freedom that optical cryptosystems offer. Asymmetric cryptosystems have been introduced as an upgrade over the conventional double random phase encoding technique and they show resistance towards the known-plaintext attack. This paper reviews the symmetric and asymmetric cryptosystems and their attack analysis.

In the present paper, a systematic method useful in the structural design and motion synthesis of motion assist exoskeleton. To this end, a method for analyzing complex human motions with multiple degrees of freedom for different functions and for regenerating arbitrary motions from the analyzed data by adjusting parameters based on the principal component analysis is described. An illustrative example on the design of walking assist device for hemiplegics is presented.

Early research on a new concept for a morphing system based on unit structures or cells containing pressurized fluid is presented in this article. The motivation stems from the desire to achieve 3D smooth variations with multiple degrees of freedom and variations in surface area. Such a cell is composed of a hybrid between elastomeric material and stiffening material, creating an orthotropic system. When connected in a network of cells, the morphing system is highly integrated in terms of the components of the skin, substructure and actuation means. Numerical predictions of small simple prismatic cells show a force and axial strain capability of above 200 N and 14% respectively for typical elastomeric and stiffening materials at 8 bar pressure. PolyJet™ additively-manufactured models of wings show how such actuators can be integrated into aircraft structures, including when 3D geometry is highly challenging. These additively-manufactured models were operated at low pressures in the order of 0.5 bar, and a number of open questions on the design, manufacture and operation of such structures are discussed along with intended future work towards higher grade materials and working pressures.

Technological advances in multi-articulated prosthetic hands have outpaced the development of methods to intuitively control these devices. In fact, prosthetic users often cite "difficulty of use" as a key contributing factor for abandoning their prostheses. To overcome the limitations of the currently pervasive myoelectric control strategies, namely unintuitive proportional control of multiple degrees-of-freedom, we propose a novel approach: proprioceptive sonomyographiccontrol. Unlike myoelectric control strategies which measure electrical activation of muscles and use the extracted signals to determine the velocity of an end-effector; our sonomyography-based strategy measures mechanical muscle deformation directly with ultrasound and uses the extracted signals to proportionally control the position of an end-effector. Therefore, our sonomyography-based control is congruent with a prosthetic user’s innate proprioception of muscle deformation in the residual limb. In this work, we evaluated proprioceptive sonomyographic control with 5 prosthetic users and 5 able-bodied participants in a virtual target achievement and holding task for 5 different hand motions. We observed that with limited training, the performance of prosthetic users was comparable to that of able-bodied participants and thus conclude that proprioceptive sonomyographic control is a robust and intuitive prosthetic control strategy.

Ahstract- Unmanned exploration by robots for volcanic environnements has been required. A tracked vehicle is one good candidate. When a tracked vehicle traverses volcanic environment, it faces tip-over because the ground in a volcanic environment is tilted and frequently covered with large rocks and a tracked vehicle climb over such obstacles on a slope. On the other hand, to increase the traversability, various multiple degrees of freedom tracked vehicles equipped with sub-tracks have been proposed. However, the relationship between tip-over condition on a slope and the sub-track's motion has not been sufficiently researched. The primary purposes of this study are to understand the tip-over phenomena for a tracked vehicle with sub-tracks climbing an obstacle on a slope, and to provide the optimal motion strategy. In this paper, the geometric tip-over condition for each sub-track angle and the motion strategy based on the posture at the moment of climbing over were considered. Moreover, experiments were conducted to validate the usefulness of the proposed method. From the results, the derived condition is valid if the robot does not slide down.

International audience; We present an application of the input shaping technique on infinite dimensional systems such as systems described by PDEs. The presented method is a feedforward scheme which allows to target multiple modes of a flexible system and also provide robustness with respect to parameters variations. The method is based on recently developed input shaper with multiple degrees of freedom that are needed to meet all constraints for the given task. We show that, even though the system consists of infinitely many modes, it is required to target only dominant ones. In addition, the method is illustrated on a case example of oil well drilling.

Reconfigurable mechanisms are a relatively recent contribution to the field of mechanism design and authors have only just been producing real-life applications of these mechanisms. This paper builds on the application of two categories of reconfigurable mechanisms by elaborating on a generalised static balancing theory suggested in a previous review paper [1]. These categories are single loop mechanisms with one degree of freedom per mode, and single loop mechanisms with multiple degrees of freedom per mode. In this paper it is shown that all configurations of the single DoF mechanisms can be balanced using a single spring. The multiple DoF mechanisms can be balanced by balancing each link with respect to the previous link. These balancing strategies are mathematically shown to be valid. The balancing strategy is then applied to a reconfigurable rehabilitation mechanism for patients with a lower limb paralysis by Tseng et al. [2] of which a simulation and a prototype is made to validate the theory. From the simulation and prototype follows that the single spring balancing of multiple configurations of a single DoF mechanism is possible.

With rapid development of assistive technologies, robots have been adopted to assist impaired persons to perform daily functions. To increase functionality of robotic arm in grasping, a universal robotic gripper consists of multiple degrees of freedom (DOF) is proposed and examined in this paper. Through modelling, simulation, and mechatronics integration, the proposed gripper design is validated to be able to morph its shape to adapt objects with various shapes. Compliance of the gripper in grasping is also validated, which can increase the safety should it be included in assistive devices.

We developed a new technique for measuring the thermodynamic entropy as a function of the magnetic field angle. This technique enables high-resolution angle-resolved measurements of the entropy in an unprecedentedly short measuring time. When the magnetic field is rotated under adiabatic conditions, the sample temperature changes owing to the field-angle variation of its entropy, which is referred to as the rotational magnetocaloric effect. By investigating this effect along with the specific heat, the field-angle dependence of the entropy can be determined. To demonstrate this technique, we chose the spin-ice compound Dy$_2$Ti$_2$O$_7$ as a benchmark and showed good agreement between the measured and theoretical entropies as a function of the field angle. This development provides a new approach to studying condensed-matter physics, in which multiple degrees of freedom play an important role., 5 pages, 6 figures, published in J. Phys. Soc. Jpn

The Feature Selective Validation (FSV) method is both a de factor and de jure standard for comparing data for validation of computational electromagnetics in the EMC domain. However, the “domain agnostic” approach means that it is also seeing application outside its initial area of application. The focus of development was mostly on comparisons of, or with, numerical data but the potential application to measured data was proposed but has not been fully investigated. This paper addresses radio frequency EMC characterization applications of FSV with a view to assessing its suitability for a new IEEE Standards Project, P2665, “Statistical Process Control for EMC Test Laboratories”. The conclusions are that the FSV technique may, indeed, provide a suitable objective comparison method for visually complex data or for data that requires comparison with multiple degrees of freedom but further analysis is required in order to define the clear limits of operation.

Skilled performance, in many situations, exposes an individual to psychological stress and fear, thus triggering state anxiety and compromising motor dexterity. Suboptimal skill execution in people under pressure affects the future career prospects of trained individuals, such as athletes, clinicians, and musicians. However, it has not been elucidated in what manner state anxiety affects multijoint movements and thereby degrades fine motor control. Using principal component analysis of hand kinematics recorded by a data glove during piano performances, we tested whether state anxiety affects the organization of movements of multiple joints or merely constrains the amplitude of the individual joints without affecting joint movement coordination. The result demonstrated changes in the coordination of movements across joints in piano performances by experts under psychological stress. Overall, the change was characterized by reduction of synergistic movements between the finger responsible for the keypress and its adjacent fingers. A regression analysis further identified that the attenuation of the movement covariation between the fingers was associated with an increase in temporal error during performance under pressure. In contrast, neither the maximum nor minimum angles of the individual joints of the hand were susceptible to induced anxiety. These results suggest that degradation of fine motor control under pressure is mediated by incoordination of movements between the fingers in skilled piano performances. NEW & NOTEWORTHY A key issue in neuromuscular control of coordinated movements is how the nervous system organizes multiple degrees of freedom for production of skillful motor behaviors. We found that state anxiety disorchestrates the organization of finger movements so as to decrease synergistic motions between the fingers in musical performance, which degrades fine motor control. The findings are important to shed light on mechanisms underlying loss of motor dexterity under pressure.

Technological advances in multi-articulated prosthetic hands have outpaced the methods available to amputees to intuitively control these devices. Amputees often cite difficulty of use as a key contributing factor for abandoning their prosthesis, creating a pressing need for improved control technology. A major challenge of traditional myoelectric control strategies using surface electromyography electrodes has been the difficulty in achieving intuitive and robust proportional control of multiple degrees of freedom. In this paper, we describe a new control method, proprioceptive sonomyographic control that overcomes several limitations of myoelectric control. In sonomyography, muscle mechanical deformation is sensed using ultrasound, as compared to electrical activation, and therefore the resulting control signals can directly control the position of the end effector. Compared to myoelectric control which controls the velocity of the end-effector device, sonomyographic control is more congruent with residual proprioception in the residual limb. We tested our approach with 5 upper-extremity amputees and able-bodied subjects using a virtual target achievement and holding task. Amputees and able-bodied participants demonstrated the ability to achieve positional control for 5 degrees of freedom with an hour of training. Our results demonstrate the potential of proprioceptive sonomyographic control for intuitive dexterous control of multiarticulated prostheses.

Invasive brain–computer interfaces (BCIs) have been developed to enable the direct communication between the brain and a computer or another external device. Unlike noninvasive BCI that have a lower spatial resolution, invasive BCI have the potential to record the activity of single neurons. The clinical long-term aim of these interfaces has always been to allow severely paralyzed individuals to regain some autonomy and to increase their quality of life. In recent years, several groups could show that complex movements, with multiple degrees of freedom, can be decoded from the recorded brain signals. At the same time, this technology has also made it possible to “peek” into living and intact human brains on a single neuron level while the person is thinking and acting. In the near future, we will have an increasing amount of neuronal recordings from humans, which will allow valuable new insights into the living human brain. In this chapter, we will discuss current BCI methodology and state-of-the-art advances in the field of human neural recordings.

By treating coherence as a shareable resource between multiple degrees of freedom (DoFs), we experimentally demonstrate a reversible exchange of coherence between polarization and spatial DoFs using only unitary transformations.