bluuebunny/crossref_metadata_2025 huggingface dataset:
Particle Filter Tracking without Dynamics
Authors: Ortegon-Aguilar Jaime , Bayro-Corrochano Eduardo
Published: March 2015

People tracking is an interesting topic in computer vision. It has applications in industrial areas such as surveillance or human-machine interaction. Particle Filters is a common algorithm for people tracking; challenging situations occur when the target's motion is poorly modelled or with unexpected motions. In this paper, an alternative to address people tracking is presented. The proposed algorithm is based in particle filters, but instead of using a dynamical model, it uses background subtraction to predict future locations of particles. The algorithm is able to track people in omnidirectional sequences with a low frame rate (one or two frames per second). Our approach can tackle unexpected discontinuities and changes in the direction of the motion. The main goal of the paper is to track people from laboratories, but it has applications in surveillance, mainly in controlled environments.
Toward Low-Cost Highly Portable Tactile Displays with Shape Memory Alloys
Authors: Velázquez R. , Pissaloux E. E. , Hafez M. , Szewczyk J.
Published: March 2015

This paper presents a new concept of low-cost, high-resolution, lightweight, compact and highly portable tactile display. The prototype consists of an array of 8 × 8 upward/downward independent moveable pins based on shape memory alloy (SMA) technology. Each tactile actuator consists of an antagonist arranged pair of miniature NiTi SMA helical springs capable of developing a 300 mN pull force at 1.5 Hz bandwidth by using simple forced-air convection. The proposed concept allows the development of 200 g weight tactile instruments of compact dimensions which can be easily carried by a visually disabled user. A detailed technical description of the SMA active element, tactile actuator and tactile display is presented and discussed. Preliminary perceptual results confirm the effectiveness of the display on information transmission.
Synthetic Versus Tissue-Engineered Implants for Joint Replacement
Authors: Shepherd Duncan E. T. , Azangwe Godfrey
Published: March 2015

Human synovial joints are remarkable as they can last for a lifetime. However, they can be affected by disease that may lead to destruction of the joint surface. The most common treatment in the advanced stages of joint disease is artificial joint replacement, where the diseased synovial joint is replaced with an artificial implant made from synthetic materials, such as metals and polymers. A new technique for repairing diseased synovial joints is tissue engineering where cells are used to grow replacement tissue. This paper explores the relative merits of synthetic and tissue-engineered implants, using joint replacement as an example. Synthetic joint replacement is a well-established procedure with the advantages of early mobilisation, pain relief and high patient satisfaction. However, synthetic implants are not natural tissues; they can cause adverse reactions to the body and there could be a mismatch in mechanical properties compared to natural tissues. Tissue-engineered implants offer great potential and have major advantages over synthetic implants as they are natural tissue, which should ensure that they are totally biocompatible, have the correct mechanical properties and integrate well with the existing tissue. However, there are still many limitations to be addressed in tissue engineering such as scaling up for production, bioreactor design, appropriate regulation and the potential for disease to attack the new tissue-engineered implant.
Design Issues and Application of Cable-Based Parallel Manipulators for Rehabilitation Therapy
Authors: Ottaviano E.
Published: March 2015

In this study, cable-based manipulators are proposed for application in rehabilitation therapies. Cable-based manipulators show good features that are very useful when the system has to interact with humans. In particular, they can be used to aid motion or as monitoring/training systems in rehabilitation therapies. Modelling and simulation of both active and passive cable-based parallel manipulators are presented for an application to help older people, patients or disabled people in the sit-to-stand transfer and as a monitoring/training system. Experimental results are presented by using built prototypes.
The Influence of a Micropolar Fluid on Peristaltic Transport in an Annulus: Application of the Clot Model
Authors: Mekheimer Kh. S. , Elmaboud Y. Abd
Published: March 2015

A serious pathological condition is encountered when some blood constituents deposited on the blood vessels get detached from the wall, join the blood stream again and form a clot. Study of the peristaltic transport of a micropolar fluid in an annular region is investigated under low Reynolds number and long wavelength approximations. We model a small artery as a tube having a sinusoidal wave travelling down its wall and a clot model inside it. Closed form solutions are obtained for the velocity and the microrotation components, as well as the stream function, and they contain new additional parameters, namely, δ, the height of the clot,N, the coupling number andm, the micropolar parameter. The pressure rise and friction force on the inner and the outer tubes have been discussed for various values of the physical parameters of interest.
PLZT-Modified Relaxor Piezoelectric Ceramic System for Medical Diagnostic Applications
Authors: Ramam Koduri , Lopez Marta
Published: March 2015

The piezoelectric ceramic system [Pb0.978–yLa0.012Ba0.01Sry][(Zr0.534Ti0.466)0.987Nb0.008]O3(PLBSZNT) has been fabricated for use in medical diagnostics applications. The fundamental pre-requisites are high-density, high dielectric constant and high piezoelectric properties that serve as compatible ceramic materials for medical diagnostic applications. It is essential for sensitive transducers that the piezoelectric ceramics must efficiently convert between electrical and mechanical energy, and so the electromechanical coupling coefficients should be high, as the fabrication process of tiny elements for medical arrays must be carried out without damaging the material and its properties. In our study, Sr-modified PLBZNT had shown single ferroelectric tetragonal phase. An analysis of different Sr doping concentration is reported, and the high dielectric permittivity, low dielectric loss along with high electromechanical properties indicate that PLBSZNT is suitable for medical diagnostic applications as well as sensors and actuators.
No Need for a Body Model: Positive Velocity Feedback for the Control of an 18-DOF Robot Walker
Authors: Schmitz Josef , Schneider Axel , Schilling Malte , Cruse Holk
Published: March 2015

In a multilegged walking robot several legs usually have ground contact and thereby form a closed kinematic chain. The control of such a system is generally assumed to require the explicit calculation of the body kinematics. Such a computation requires knowledge concerning all relevant joint angles as well as the segment lengths. Here, we propose a biologically inspired solution that does not need such a body model. This is done by using implicit communication through the body mechanics (embodiment) and a local positive velocity feedback strategy (LPVF) on the single joint level. In this control scheme the locally measured joint velocity of an elastic joint is fed into the same joint during the next time step to maintain the movement. At the same time, an additional part of this joint controller observes the mechanical joint power to confine the positive feedback. This solution does not depend on changes of the geometry, e.g. length of individual segments, and allows for a simple solution of negotiation of curves. The principle is tested in a dynamics simulation on a six-legged walker and, for the first time, also on a real robot.
Animal-Inspired Sensing for Autonomously Climbing or Avoiding Obstacles
Authors: Lewinger William A. , Harley Cynthia M. , Watson Michael S. , Branicky Michael S. , Ritzmann Roy E. , Quinn Roger D.
Published: March 2015

The way that natural systems navigate their environments with agility, intelligence and efficiency is an inspiration to engineers. Biological attributes such as modes of locomotion, sensory modalities, behaviours and physical appearance have been used as design goals. While methods of locomotion allow robots to move through their environment, the addition of sensing, perception and decision making are necessary to perform this task with autonomy. This paper contrasts how the addition of two separate sensing modalities – tactile antennae and non-contact sensing – and a low-computation, capable microcontroller allow a biologically abstracted mobile robot to make insect-inspired decisions when encountering a shelflike obstacle, navigating a cluttered environment without collision and seeking vision-based goals while avoiding obstacles.
On Control of Reaching Movements for Musculo-Skeletal Redundant Arm Model
Authors: Tahara Kenji , Arimoto Suguru , Sekimoto Masahiro , Luo Zhi-Wei
Published: March 2015

This paper focuses on a dynamic sensory-motor control mechanism of reaching movements for a musculo-skeletal redundant arm model. The formulation of a musculo-skeletal redundant arm system, which takes into account non-linear muscle properties obtained by some physiological understandings, is introduced and numerical simulations are perfomed. The non-linear properties of muscle dynamics make it possible to modulate the viscosity of the joints, and the end point of the arm converges to the desired point with a simple task-space feedback when adequate internal forces are chosen, regardless of the redundancy of the joint. Numerical simulations were performed and the effectiveness of our control scheme is discussed through these results. The results suggest that the reaching movements can be achieved using only a simple task-space feedback scheme together with the internal force effect that comes from non-linear properties of skeletal muscles without any complex mathematical computation such as an inverse dynamics or optimal trajectory derivation. In addition, the dynamic damping ellipsoid for evaluating how the internal forces can be determined is introduced. The task-space feedback is extended to the ‘virtual spring-damper hypothesis’ based on the research by Arimoto et al. (2006) to reduce the muscle output forces and heterogeneity of convergence depending on the initial state and desired position. The research suggests a new direction for studies of brain-motor control mechanism of human movements.
Optimal Limb Length Ratio of Quadruped Robot Minimising Joint Torque on Slopes
Authors: Aoyama Tadayoshi , Sekiyama Kosuke , Hasegawa Yasuhisa , Fukuda Toshio
Published: March 2015

This paper aims to determine an optimal structure for a quadruped robot, which will allow the robot’s joint torque sum to be minimised. An animal’s characteristic limb length ratio is a vital part of its overall morphology and the one that enables it to travel easily through its environment. For the same reason, a robot’s structure needs to be suitably designed for locomotion in its working environment. Joint torques are necessary to maintain the posture of the robot and to accelerate joint angles during walking motion, hence, minimisation of joint torques reduces energy consumption. We performed a numerical simulation in which we analysed the joint torques for various limb lengths and slope angles in order to determine the optimal structure of a robot walking on a slope. Our investigation determines that the optimal Ratio of Rear Leg Length (RRL) can be derived by the use of a simulation designed to determine the physical structure of quadruped robot. Our analysis suggests that joint torque will increase as the slope angle becomes steeper if the rear legs of the robot are shorter than its forelegs, and that joint torque will decrease as the slope angle declines if the robot’s forelegs are shorter than its rear legs. Finally, experimental results validated our simulation analysis.
KASPAR – A Minimally Expressive Humanoid Robot for Human–Robot Interaction Research
Authors: Dautenhahn Kerstin , Nehaniv Chrystopher L. , Walters Michael L. , Robins Ben , Kose-Bagci Hatice , Mirza N. Assif , Blow Mike
Published: March 2015

This paper provides a comprehensive introduction to the design of the minimally expressive robot KASPAR, which is particularly suitable for human–robot interaction studies. A low-cost design with off-the-shelf components has been used in a novel design inspired from a multi-disciplinary viewpoint, including comics design and Japanese Noh theatre. The design rationale of the robot and its technical features are described in detail. Three research studies will be presented that have been using KASPAR extensively. Firstly, we present its application in robot-assisted play and therapy for children with autism. Secondly, we illustrate its use in human–robot interaction studies investigating the role of interaction kinesics and gestures. Lastly, we describe a study in the field of developmental robotics into computational architectures based on interaction histories for robot ontogeny. The three areas differ in the way as to how the robot is being operated and its role in social interaction scenarios. Each will be introduced briefly and examples of the results will be presented. Reflections on the specific design features of KASPAR that were important in these studies and lessons learnt from these studies concerning the design of humanoid robots for social interaction will also be discussed. An assessment of the robot in terms of utility of the design for human–robot interaction experiments concludes the paper.
Binaural Active Audition for Humanoid Robots to Localise Speech over Entire Azimuth Range
Authors: Kim Hyun-Don , Komatani Kazunori , Ogata Tetsuya , Okuno Hiroshi G.
Published: March 2015

We applied motion theory to robot audition to improve the inadequate performance. Motions are critical for overcoming the ambiguity and sparseness of information obtained by two microphones. To realise this, we first designed a sound source localisation system integrated with cross-power spectrum phase (CSP) analysis and an EM algorithm. The CSP of sound signals obtained with only two microphones was used to localise the sound source without having to measure impulse response data. The expectation-maximisation (EM) algorithm helped the system to cope with several moving sound sources and reduce localisation errors. We then proposed a way of constructing a database for moving sounds to evaluate binaural sound source localisation. We evaluated our sound localisation method using artificial moving sounds and confirmed that it could effectively localise moving sounds slower than 1.125 rad/s. Consequently, we solved the problem of distinguishing whether sounds were coming from the front or rear by rotating and/or tipping the robot's head that was equipped with only two microphones. Our system was applied to a humanoid robot called SIG2, and we confirmed its ability to localise sounds over the entire azimuth range as the success rates for sound localisation in the front and rear areas were 97.6% and 75.6% respectively.
IKO: A Five Actuated DoF Upper Limb Exoskeleton Oriented to Workplace Assistance
Authors: Martinez Felix , Pujana-Arrese Aron , Retolaza Iban , Sacristan Irantzu , Basurko Jon , Landaluze Joseba
Published: March 2015

IKerlan’s Orthosis (IKO) is an upper limb exoskeleton oriented to increasing human force during routine activity at the workplace. Therefore, it can be considered as a force-amplification device conceived to work in collaboration with the human arm and implementing biomimetic principles. The aim of the proposed design is to find the best compromise between maximum reachable workspace and minimum moving mass, which are the key factors for obtaining an ergonomic, wearable exoskeleton. It consists of five actuated degree of freedom (DoF) to move the human arm and three non-actuated DoF between the back and shoulder to allow relative displacement of the sterno-clavicular joint. Conventional electrical motors are used for most of the DoF and pneumatic muscles for one of them (forearm rotation). Power transmission is based on Bowden cables. This paper presents the IKO design, the mechanical structure of a first prototype and the redesign process from an aesthetic point of view. Controller set-up and control strategies are also shown, together with dynamic performance from experimental results.
The Rh-1 Full-Size Humanoid Robot: Design, Walking Pattern Generation and Control
Authors: Arbulú M. , Kaynov D. , Cabas L. , Balaguer C.
Published: March 2015

This paper is an overview of the humanoid robot Rh-1, the second phase of the Rh project, which was launched by the Robotics Lab at the Carlos III University of Madrid in 2002. The robot mechanical design includes the specifications development in order to construct a platform, which is capable of stable biped walking. At first, the robots’ weights were calculated in order to obtain the inverse dynamics and to select the actuators. After that, mechanical specifications were introduced in order to verify the robot’s structural behaviour with different experimental gaits. In addition, an important aspect is the joints design when their axes are crossed, which is called ‘Joints of Rectangular Axes’ (JRA). The problem with these joints is obtaining two or more degrees of freedom (DOF) in small space. The construction of a humanoid robot also includes the design of hardware and software architectures. The main advantage of the proposed hardware and software architectures is the use of standardised solutions frequently used in the automation industry and commercially available hardware components. It provides scalability, modularity and application of standardised interfaces and brings the design of the complex control system of the humanoid robot out of a closed laboratory to industry. Stable walking is the most essential ability for the humanoid robot. The three dimensional Linear Inverted Pendulum Model (3D-LIPM) and the Cart-table models had been used in order to achieve natural and dynamic biped walking. Humanoid dynamics is widely simplified by concentrating its mass in the centre of gravity (COG) and moving it following the natural inverted pendulum laws (3D-LIPM) or by controlling the cart motion (Cart-table model). An offline-calculated motion pattern does not guarantee the walking stability of the humanoid robot. Control architecture for the dynamic humanoid robot walking was developed, which is able to make online modifications of the motion patterns in order to adjust it to the continuously changing environment. Experimental results concerning biped locomotion of the Rh-1 humanoid robot are presented and discussed.
Influence of Magnetic Field on the Peristaltic Flow of a Viscous Fluid through a Finite-Length Cylindrical Tube
Authors: Pandey S. K. , Tripathi Dharmendra
Published: March 2015

The paper presents an analytical investigation of the peristaltic transport of a viscous fluid under the influence of a magnetic field through a tube of finite length in a dimensionless form. The expressions of pressure gradient, volume flow rate, average volume flow rate and local wall shear stress have been obtained. The effects of the transverse magnetic field and electrical conductivity (i.e. the Hartmann number) on the mechanical efficiency of a peristaltic pump have also been studied. The reflux phenomenon is also investigated. It is concluded, on the basis of the pressure distribution along the tubular length and pumping efficiency, that if the transverse magnetic field and the electric conductivity increase, the pumping machinery exerts more pressure for pushing the fluid forward. There is a linear relation between the averaged flow rate and the pressure applied across one wavelength that can restrain the flow due to peristalsis. It is found that there is a particular value of the averaged flow rate corresponding to a particular pressure that does not depend on the Hartmann number. Naming these values ‘critical values’, it is concluded that the pressure required for checking the flow increases with the Hartmann number above the critical value and decreases with it below the critical value. It is also inferred that magneto-hydrodynamic parameters make the fluid more prone to flow reversal. The conclusion applied to oesophageal swallowing reveals that normal water is easier to swallow than saline water. The latter is more prone to flow reversal. A significant difference between the propagation of the integral and non-integral number of waves along the tube is that pressure peaks are identical in the former and different in the latter cases.
Motion Analysis of Thumb in Cellular Phone Use
Authors: Sakai Naotaka , Shimawaki Satoshi
Published: March 2015

The thumb motion of 10 normal subjects during cellular phone use was measured using a reflective marker detection system to compare the maximum, minimum and range of flexion angles of the interphalangeal (IP), metacarpophalangeal (MP) and carpometacarpal (CM) joints. Two micro-reflective markers 3 mm in diameter were each placed on the dorsal surface of the distal phalanx, basal phalanx and metacarpal bone of the thumb. Three markers were placed on the dorsal hand in order to define the dorsal hand plane. Each subject pushed the 12 keys of a folding cellular phone with an 85-mm-long and 40-mm-wide keypad, sequentially from ‘1’ to ‘#’, and the pushing motion was recorded by six infrared video cameras for 12 seconds, using the VICON 612 system. The mean maximum flexion angle of the MP joint was significantly (p< .05) larger than the CM joint, and the mean minimum flexion angle of the CM joint was significantly (p< .01) smaller than the IP and MP joints. The mean range of motion of the IP joint was significantly (p< .05) larger than the MP and the CM joints. In a comparison of different key-pushing motions, only the CM joint was significantly (p< .05) larger in its range of motion. In conclusion, thumb motion on pushing the keys of the cellular phone was produced mainly by the MP and the CM joints. In addition, the ability to reach keys in different areas of the cellular phone keypad is regulated by changing the flexion angle of the CM joint.
Immobilisation of a Large Animal for Imaging Purposes
Authors: Szyszkowski W. , Cai Wei
Published: March 2015

The mobility of a horse in the standing position with its hooves fixed to the ground is investigated to assist designing a minimally obstructing system for restraining large animals. The horse is modelled as a mechanical linkage driven by muscle forces. The linkage's configuration patterns, active joints and the forces associated with motion initiation are studied by reducing it to a mechanism with a low number of degrees of freedom. A restraint system blocking the motion of active joints with ropes is proposed as an alternative to massive mechanical devices restraining the whole body. The system has been verified experimentally on a sheep.
The Influence of Slippage on Trapping and Reflux Limits with Peristalsis through an Asymmetric Channel
Authors: Gharsseldien Z. M. , Mekheimer Kh. S. , Awad A. S.
Published: March 2015

The effects of slip boundary condition on peristaltic transport of incompressible Newtonian viscous fluid in an asymmetric channel is investigated, under the conditions of low Reynolds number and long wavelength. The pumping characteristics, trapping and reflux limits are studied for different values of the dimensionless slip parameterβ.
Robotics as a Support Tool for Experimental Optimisation of Surgical Strategies in Orthopaedic Surgery
Authors: Frigola Manel , Vinagre Manuel , Casals Alicia , Amat Josep , Santana Fernando , Torrens Carlos
Published: March 2015

Robotics has shown its potential not only in assisting the surgeon during an intervention but also as a tool for training and for surgical procedure's evaluation. Thus, robotics can constitute an extension of simulators that are based on the high capabilities of computer graphics. In addition, haptics has taken a first step in increasing the performance of current virtual reality systems based uniquely on computer simulation and their corresponding interface devices. As a further step in the field of training and learning in surgery, this work describes a robotic experimental workstation composed of robots and specific measuring devices, together with their corresponding control and monitoring strategies for orthopaedic surgery. Through a case study, humerus arthroplasty, experimental evaluation shows the possibilities of having a test bed available for repetitive and quantifiable trials, which make a reliable scientific comparison between different surgical strategies possible.
Tracking of Brain Tumors using Vision and Neurosonography
Authors: Cadena Rubén Machucho , de la Cruz Rodríguez Sergio , Bayro-Corrochano Eduardo
Published: March 2015

We have developed a method to render brain tumours from endoneurosonography. We propose to track an ultrasound probe in successive endoscopic images without relying on an external optic or magnetic tracking system. The probe is tracked using two different methods: one of them based on a generalised Hough transform and the other one based on particle filters. By estimating the pose of the ultrasound probe in several contiguous images, we use conformal geometric algebra to compute the geometric transformations that yield the 3D position of the tumour, which was segmented in the ultrasound image using morphological operators. We use images from brain phantoms to evaluate the performance of the proposed methods, and our results show that they are robust.
Controlling Underwater Robots with Electronic Nervous Systems
Authors: Ayers Joseph , Rulkov Nikolai , Knudsen Dan , Kim Yong-Bin , Volkovskii Alexander , Selverston Allen
Published: March 2015

We are developing robot controllers based on biomimetic design principles. The goal is to realise the adaptive capabilities of the animal models in natural environments. We report feasibility studies of a hybrid architecture that instantiates a command and coordinating level with computed discrete-time map-based (DTM) neuronal networks and the central pattern generators with analogue VLSI (Very Large Scale Integration) electronic neuron (aVLSI) networks. DTM networks are realised using neurons based on a 1-D or 2-D Map with two additional parameters that define silent, spiking and bursting regimes. Electronic neurons (ENs) based on Hindmarsh–Rose (HR) dynamics can be instantiated in analogue VLSI and exhibit similar behaviour to those based on discrete components. We have constructed locomotor central pattern generators (CPGs) with aVLSI networks that can be modulated to select different behaviours on the basis of selective command input. The two technologies can be fused by interfacing the signals from the DTM circuits directly to the aVLSI CPGs. Using DTMs, we have been able to simulate complex sensory fusion for rheotaxic behaviour based on both hydrodynamic and optical flow senses. We will illustrate aspects of controllers for ambulatory biomimetic robots. These studies indicate that it is feasible to fabricate an electronic nervous system controller integrating both aVLSI CPGs and layered DTM exteroceptive reflexes.
A Biologically Derived Pectoral Fin for Yaw Turn Manoeuvres
Authors: Gottlieb Jonah R. , Tangorra James L. , Esposito Christopher J. , Lauder George V.
Published: March 2015

A bio-robotic fin has been developed that models the pectoral fin of the bluegill sunfish as the fish turned to avoid an obstacle. This work involved biological studies of the sunfish fin, the development of kinematic models of the motions of the fin's rays, CFD based predictions of the 3D forces and flows created by the fin, and the implementation of simplified models of the fin's kinematics and mechanical properties in a physical model. The resulting robotic fin produced the forces and flows that drove the manoeuvre and had a sufficiently high number of degrees of freedom to create a variety of non-biologically derived motions. The results indicate that for robotic fins to produce a level of performance on par with biological fins, both the kinematics and the mechanical properties of the biological fin must be modelled well.
Finite Element Analysis of Normal Pressure Hydrocephalus: Influence of CSF Content and Anisotropy in Permeability
Authors: Shahim K. , Drezet J.-M. , Molinari J.-F. , Sinkus R. , Momjian S.
Published: March 2015

Hydrocephalus is a cerebral disease where brain ventricles enlarge and compress the brain parenchyma towards the skull leading to symptoms like dementia, walking disorder and incontinence. The origin of normal pressure hydrocephalus is still obscure. In order to study this disease, a finite element model is built using the geometries of the ventricles and the skull measured by magnetic resonance imaging. The brain parenchyma is modelled as a porous medium fully saturated with cerebrospinal fluid (CSF) using Biot's theory of consolidation (1941). Owing to the existence of bundles of axons, the brain parenchyma shows locally anisotropic behaviour. Indeed, permeability is higher along the fibre tracts in the white matter region. In contrast, grey matter is isotropic. Diffusion tensor imaging is used to establish the local CSF content and the fibre tracts direction together with the associated local frame where the permeability coefficients are given by dedicated formulas. The present study shows that both inhomogeneous CSF content and anisotropy in permeability have a great influence on the CSF flow pattern through the parenchyma under an imposed pressure gradient between the ventricles and the subarachnoid spaces.
Effect of Lateral Walls on Peristaltic Flow through an Asymmetric Rectangular Duct
Authors: Mekheimer Kh. S. , Husseny S. Z.-A. , Abd el Lateef A. I.
Published: March 2015

Peristaltic transport of an incompressible viscous fluid due to an asymmetric waves propagating on the horizontal sidewalls of a rectangular duct is studied under long-wavelength and low-Reynolds number assumptions. The peristaltic wave train on the walls have different amplitudes and phase. The flow is investigated in a wave frame of reference moving with velocity of the wave. The effect of aspect ratio, phase difference, varying channel width and wave amplitudes on the pumping characteristics and trapping phenomena are discussed in detail. The results are compared to with those corresponding to Poiseuille flow.
Comparative Review of Endoscopic Devices Articulations Technologies Developed for Minimally Invasive Medical Procedures
Authors: Catherine Julien , Rotinat-Libersa Christine , Micaelli Alain
Published: March 2015

This study introduces a comparative performance analysis of the technological solutions that have been used to build distal active articulations for minimally invasive medical procedures. The aim is to provide a practical and concise database and classification tool for anyone that wants to learn more about the technologies involved in minimally invasive medical devices, or for any designer interested in further improving these devices. A review of the different articulations developed in this field is therefore performed and organized by both actuation technology and structural architecture. Details are presented concerning the mechanical structures as well as the actuation and the mechanical transmission technologies available. The solutions are evaluated keeping as a reference some chosen required performances and characteristics for minimally invasive surgical procedures. Finally, a quantified comparison chart of these devices is given regarding selected criteria of interest for minimally invasive surgical application.
Integration of New Features for Telerobotic Surgery into The Mirosurge System
Authors: Konietschke Rainer , Zerbato Davide , Richa Rogério , Tobergte Andreas , Poignet Philippe , Fröhlich Florian A. , Botturi Debora , Fiorini Paolo , Hirzinger Gerd
Published: March 2015

Minimally invasive robotic surgery has gained wide acceptance recently. Computer-aided features to assist the surgeon during these interventions may help to develop safer, faster, and more accurate procedures. Especially physiological motion compensation of the beating heart and online soft tissue modelling are promising features that were developed recently. This paper presents the integration of these new features into the minimally invasive robotic surgery platform MiroSurge. A central aim of this research platform is to enable evaluation and comparison of new functionalities for minimally invasive robotic surgery. The system structure of MiroSurge is presented as well as the interfaces for the new functionalities. Some details about the modules for motion tracking and for soft tissue simulation are given. Results are shown with an experimental setup that includes a heart motion simulator and dedicated silicone organ models. Both features are integrated seamlessly and work reliably in the chosen setup. The MiroSurge platform thus shows the potential to provide valuable results in evaluating new functionalities for minimally invasive robotic surgery.
Teletactile System Based on Mechanical Properties Estimation
Authors: Sette Mauro M. , Van Brussel Hendrik , Sloten Jos Vander
Published: March 2015

Tactile feedback is a major missing feature in minimally invasive procedures; it is an essential means of diagnosis and orientation during surgical procedures. Previous works have presented a remote palpation feedback system based on the coupling between a pressure sensor and a general haptic interface. Here a new approach is presented based on the direct estimation of the tissue mechanical properties and finally their presentation to the operator by means of a haptic interface. The approach presents different technical difficulties and some solutions are proposed: the implementation of a fast Young’s modulus estimation algorithm, the implementation of a real time finite element model, and finally the implementation of a stiffness estimation approach in order to guarantee the system’s stability. The work is concluded with an experimental evaluation of the whole system.
Smooth and Energy Saving Gait Planning for Humanoid Robot Using Geodesics
Authors: Zhang Liandong , Zhou Changjiu
Published: March 2015

A novel gait planning method using geodesics for humanoid robot is given in this paper. Both the linear inverted pendulum model and the exact Single Support Phase (SSP) are studied in our energy optimal gait planning based on geodesics. The kinetic energy of a 2-dimension linear inverted pendulum is obtained at first. We regard the kinetic energy as the Riemannian metric and the geodesic on this metric is studied and this is the shortest line between two points on the Riemannian surface. This geodesic is the optimal kinetic energy gait for the COG because the kinetic energy along geodesic is invariant according to the geometric property of geodesics and the walking is smooth and energy saving. Then the walking in Single Support Phase is studied and the energy optimal gait for the swing leg is obtained using our geodesics method. Finally, experiments using state-of-the-art method and using our geodesics optimization method are carried out respectively and the corresponding currents of the joint motors are recorded. With the currents comparing results, the feasibility of this new gait planning method is verified.
Proof of Concept: Model Based Bionic Muscle with Hyperbolic Force-Velocity Relation
Authors: Haeufle D. F. B. , Günther M. , Blickhan R. , Schmitt S.
Published: March 2015

Recently, the hyperbolic Hill-type force-velocity relation was derived from basic physical components. It was shown that a contractile element CE consisting of a mechanical energy source (active element AE), a parallel damper element (PDE), and a serial element (SE) exhibits operating points with hyperbolic force-velocity dependency. In this paper, a technical proof of this concept was presented. AE and PDE were implemented as electric motors, SE as a mechanical spring. The force-velocity relation of this artificial CE was determined in quick release experiments. The CE exhibited hyperbolic force-velocity dependency. This proof of concept can be seen as a well-founded starting point for the development of Hill-type artificial muscles.
Genetic Algorithms Based Approach for Designing Spring Brake Orthosis – Part Ii: Control of FES Induced Movement
Authors: Huq M. S. , Tokhi M. O.
Published: March 2015

Spring brake orthotic swing phase for paraplegic gait is initiated through releasing the brake on the knee mounted with a torsion spring. The stored potential energy in the spring, gained from the previous swing phase, is solely responsible for swing phase knee flexion. Hence the later part of the SBO operation, functional electrical stimulation (FES) assisted extension movement of the knee has to serve an additional purpose of restoring the spring potential energy on the fly. While control of FES induced movement as such is often a challenging task, a torsion spring, being antagonistically paired up with the muscle actuator, as in spring brake orthosis (SBO), only adds to the challenge. Two new schemes are proposed for the control of FES induced knee extension movement in SBO assisted swing phase. Even though the control schemes are closed-loop in nature, special attention is paid to accommodate the natural dynamics of the mechanical combination being controlled (the leg segment) as a major role playing feature. The schemes are thus found to be immune from some drawbacks associated with both closed-loop tracking as well as open-loop control of FES induced movement. A leg model including the FES knee joint model of the knee extensor muscle vasti along with the passive properties is used in the simulation. The optimized parameters for the SBO spring are obtained from the earlier part of this work. Genetic algorithm (GA) and multi-objective GA (MOGA) are used to optimize the parameters associated with the control schemes with minimum fatigue as one of the control objectives. The control schemes are evaluated in terms of three criteria based on their ability to cope with muscle fatigue.
A Mastication Mechanism Designed for Testing Temporomandibular Joint Implants
Authors: Frayne Ryan J. , Schwartz Marvin , Dickey James P.
Published: March 2015

The development of temporomandibular joint implants has involved simplified mechanical tests that apply pure vertical forces or pure rotational movements to the implant. The aim of this study was to develop a biological based mastication mechanism and conduct preliminary testing of a novel temporomandibular joint implant. The mechanism was designed to mimic temporomandibular joint loads by performing compression and anterior/posterior translation. Pilot testing was performed on six implant/joint specimens for seven consecutive hours, completing approximately 22,000 cycles at a frequency of approximately 1 Hz. Each cycle had a joint compression phase (67.3 N over 0.15 s) followed by a translation phase (8.67 N over 0.43 s) that was similar to joint loads/motions that have been reported in vivo. This new mastication mechanism incorporates both anatomical and mechanical variability. The use of biological specimens is an important approach that can help bridge the gap between traditional synthetic implant materials/mechanical testing andin vivotesting.
Exponential Fields Formulation for WMR Navigation
Authors: Martínez-García Edgar A. , Torres-Cordoba Rafael
Published: March 2015

In this manuscript, an autonomous navigation algorithm for wheeled mobile robots (WMR) operating in dynamic environments (indoors or structured outdoors) is formulated. The planning scheme is of critical importance for autonomous navigational tasks in complex dynamic environments. In fast dynamic environments, path planning needs algorithms able to sense simultaneously a diversity of obstacles, and use such sensory information to improve real-time navigation control, while moving towards a desired goal destination. The framework tackles 4 issues. 1) Reformulation of the Social Force Model (SFM) adapted to WMR; 2) the cohesion of a general inertial scheme to represents motion in any coordinate system; 3) control of actuators rotational speed as a general model regardless kinematic restrictions; 4) assuming detection of features (obstacles/goals), adaptive numeric weights are formulated to affect navigational exponential components. Simulation and experimental outdoors results are presented to show the feasibility of the proposed framework.
Design of a Compact, Reconfigurable, Prosthetic Wrist
Authors: Zinck Arthur , Stavdahl Øyvind , Biden Edmund , Kyberd Peter J.
Published: March 2015

The design of a prosthetic wrist is the result of compromises between the function and the practicality of the device. Conventional prosthetic wrists use a single degree of freedom to produce pro/supination of the hand. It has not been demonstrated that this is the most functional alignment for a single axis. Previous work by the authors suggests that if the wrist must have only one rotatory axis then a more oblique orientation would be more functional. To test this idea, a compact wrist with a single axis and spherical design has been made that will allow any axis of rotation to be selected and the functional performance of the resulting arm be tested.
Physiologically Based Control Laws Featuring Antagonistic Muscle Co-Activation for Stable Compliant Joint Drives
Authors: Annunziata Salvatore , Schneider Axel
Published: March 2015

The development of robot joints ensuring controllable compliant behaviors during interaction tasks has gained the interest of the robot community in the recent years. In biological systems, while intrinsic muscle nonlinear elasticity allows the regulation of joint compliance through antagonistic co-activation, physiological control mechanisms ensure robust stability during interaction tasks both in static cases and during motion. This work presents a novel control approach for the simultaneous regulation of position and stiffness in a hinge joint driven by two muscles which combines biological findings like co-activation and reproduces reflex actions and additional influences to ensure stability. Based on the analysis of the stiffness generated in the antagonistic system and on the evaluation of stability issues when the musculoskeletal setup is loaded by external forces, a stiffness controller is proposed which integrates a stiffness computation block and an adaptive mechanism for the control of stability during interactions. The position controller, modeling physiological properties and motor-neurons, relies on reciprocal activation while the stiffness controller implements a co-activation strategy. The controller is tested in a numerical simulation using Matlab/Simulink® for different task conditions. Simulation results demonstrate the ability of the controller to simultaneously regulate position and adapt joint compliance to different external perturbations.
Functional Evaluation of Asibot: A New Approach on Portable Robotic System for Disabled People
Authors: Jardón Alberto , Monje Concepción A. , Balaguer Carlos
Published: March 2015

In this work, an innovative robotic solution for human care and assistance is presented. Our main objective is to develop a new concept of portable robot able to support the elderly and those people with different levels of disability during the execution of daily tasks, such as washing their face or hands, brushing their teeth, combing their hair, eating, drinking, and bringing objects closer, among others. Our prototype, ASIBOT, is a five degrees of freedom (DOF) self-contained manipulator that includes the control system and electronic equipment on board. The main advantages of the robot are its light weight, about 11 kg for a 1.3 m reach, its autonomy, and its ability to move between different points (docking stations) of the room or from the environment to a wheelchair and vice versa, which facilitates its supportive functions. The functional evaluation of ASIBOT is addressed in this paper. For this purpose the robotic arm is tested in different experiments with disabled people, gathering and discussing the results according to a methodology that allows us to assess users' satisfaction.
Genetic Algorithms Based Approach for Designing Spring Brake Orthosis – Part I: Spring Parameters
Authors: Huq M. S. , Tokhi M. O.
Published: March 2015

Spring brake orthosis (SBO) concentrates purely on the knee to generate the swing phase of the paraplegic gait with the required hip flexion occurring passively as a consequence of the ipsilateral knee flexion, generated by releasing the torsion spring mounted at the knee joint. Electrical stimulation then drives the knee back to full extension, as well as restores the spring potential energy. In this paper, genetic algorithm (GA) and its variant multi-objective GA (MOGA) is used to perform the search operation for the ‘best’ spring parameters for the SBO spring mounted on an average sized subject simulated in the sagittal plane. Conventional torsion spring is tested against constant torque type spring in terms of swing duration as, based on first principles, it is hypothesized that constant torque spring would be able to produce slower SBO swing phase as might be preferred in assisted paraplegic gait. In line with the hypothesis, it is found that it is not possible to delay the occurrence of the flexion peak of the SBO swing phase further than its occurrence in the natural gait. The use of conventional torsion spring causes the swing knee flexion peak to appear rather faster than that of the natural gait, resulting in a potentially faster swing phase and hence gait cycle. The constant torque type spring on the other hand is able to stretch duration of the swing phase to some extent, rendering it the preferable spring type in SBO.
Pressure Sores Prevention for Paraplegic People: Effects of Visual, Auditory and Tactile Supplementations on Overpressures Distribution in Seated Posture
Authors: Chenu Olivier , Payan Yohan , Hlavackova P. , Demongeot Jacques , Cannard Francis , Diot Bruno , Vuillerme Nicolas
Published: March 2015

This paper presents a study on the usage of different informative modalities as biofeedbacks of a perceptual supplementation device aiming at reducing overpressure at the buttock area. Visual, audio and lingual electrotactile modalities are analysed and compared with a non-biofeedback session. In conclusion, sensory modalities have a positive and equal effect, but they are not equally judged in terms of comfort and disturbance with some other activities.
Quantifying Upper-Arm Rehabilitation Metrics for Children through Interaction with a Humanoid Robot
Authors: Brooks Douglas A. , Howard Ayanna M.
Published: March 2015

The objective of this research effort is to integrate therapy instruction with child-robot play interaction in order to better assess upper-arm rehabilitation. Using computer vision techniques such as Motion History Imaging (MHI), edge detection, and Random Sample Consensus (RANSAC), movements can be quantified through robot observation. In addition, incorporating prior knowledge regarding exercise data, physical therapeutic metrics, and novel approaches, a mapping to therapist instructions can be created allowing robotic feedback and intelligent interaction. The results are compared with ground truth data retrieved via the Trimble 5606 Robotic Total Station and visual experts for the purpose of assessing the efficiency of this approach. We performed a series of upper-arm exercises with two male subjects, which were captured via a simple webcam. The specific exercises involved adduction and abduction and lateral and medial movements. The analysis shows that our algorithmic results compare closely to the results obtain from the ground truth data, with an average algorithmic error is less than 9% for the range of motion and less than 8% for the peak angular velocity of each subject.