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In recent years, wearable triboelectric nanogenerators (TENGs) have attracted attention due to its highly flexible, scalable, and low-cost features. Here in this paper, the authors have designed a sliding touch sensor which mimics the human skin to detect caressing touch based on the principle of triboelectric effect using COMSOL Multiphysics simulation software. Various triboelectric materials like Polytetrafluoroethylene(PTFE),Polyvinylchioride(PVC) and Polymethyl methacrylate(PMMA) were selected based on the triboelectric series for the comparative study on the effect of these materials on the proposed structure. The study of the device is carried out considering the voltage and charge variation obtained during the caressing of finger over the rectangular block of the polymer.

The number of extremity amputations resulting from workplace mishaps, traffic accidents and other incidents has shown an increasing trend over time, although the importance of safety management and the prevention of such accidents is fully recognized. Since precise and complex motion may be very difficult in the daily activities of amputees, the development of prosthetic systems is necessary to support their lives and enable social integration. In particular, there is a mandatory requirement for the development of externally powered prosthetic hands with a natural feeling of control, since the role played by this part of the body is very important. However, the control of such hands is problematic, and they must be carefully designed in line with the amputee’s remaining functions. Many researchers have designed prosthetic limbs for amputees since the concept was proposed by N. Wiener in Cybernetics [1]. In previous research, electromyograms (EMGs) have been widely used as an interface tool for prosthetic hands because EMG signals contain information about the operator’s intended motion [2] – [8]. For example, an EMGprosthetic hand made in the USSR [2], the Waseda hand developed by Kato et al. [3], the Boston arm by MIT [4] and the Utha artificial arm by Jacobson et al. [5] were all pioneering steps in the field. Since EMG signals also include information on the force level and mechanical impedance properties of limb motion, Akazawa et al. [6] estimated the force of flexors and extensors from these signals and proposed a scheme to use them in controlling a prosthetic hand. Abul-haj and Hogan [8] also proposed prosthetic control based on an impedance model and analyzed its control characteristics. Most previous research, however, dealt only with on/off control for prosthetic arms depending on the results of EMG pattern discrimination [2], [3], [7], or controlled only a particular joint depending on the torque estimated from EMG signals [4], [5], [6], [8]. Multijoint control of prosthetic arms considering the variable viscoelasticity of flexors and extensors has not yet been realized. This chapter introduces a biomimetic control for an externally powered multi-joint prosthetic hand that considers the muscular contraction levels of flexors and extensors using 9

In the last few decades, prosthetics has gained a noteworthy advancement within the therapeutic and bio-mechanics field. Prosthesis is originally a part of the bio-mechanics field, the science of combining electro-mechanical devices with human muscles, skeleton, nervous systems, etc. The prosthetic limbs are fantastically valuable to amputees in delivering their daily work, thereby providing a great support in the patient rehabilitation. This article focuses on the background of upper and lower limb prosthetics, the signal processing techniques, classification algorithms used and its applications for patient rehabilitation. Surface EMG (sEMG) based prostheses has been picking up in the rehabilitation field as technology progresses. The limb with EMG sensors measures and decode the electrical impulses in the muscles of the residual limb and then translate it into movement. Thus, the user is able to activate the bionic limb on his own thinking. Such developing novel technologies has revolutionized the field of prosthetics. It could be a milestone in bridging the gap between disability and ability, between human limitation and human potential.

In this digital era, technology has made its mark in almost every field. With the invention of prosthetic limbs and artificial organs among others have given people a better opportunity. The urbanization also has its downfalls. Traffic accidents can be considered as one. The initial stage treatment to a patient is very critical. The first hour is referred as the Golden Hour for this reason. Especially in the case of accidents the golden hour becomes very important. As per the Report on Road accidents in India 2019, the accident related deaths in India in 2019 were 1,51,113 in number [1]. The average time for an ambulance to reach hospital is going up each year due to increasing. So, it is imperative to find the possible ways to reduce the time. To achieve this, various measures are explored. In rescue times of greater than a half-hour, in half of the cases at least 21 min was required to communicate a need for an ambulance. [2] This article aims to reduce the time taken for the information to reach the ambulance services through a model which detects accidents and informs the ambulance service of the location of accidents.

Most prosthetic limbs can autonomously move with dexterity, yet they are not perceived by the user as belonging to their own body. Robotic limbs can convey information about the environment with higher precision than biological limbs, but their actual performance is substantially limited by current technologies for the interfacing of the robotic devices with the body and for transferring motor and sensory information bidirectionally between the prosthesis and the user. In this Perspective, we argue that direct skeletal attachment of bionic devices via osseointegration, the amplification of neural signals by targeted muscle innervation, improved prosthesis control via implanted muscle sensors and advanced algorithms, and the provision of sensory feedback by means of electrodes implanted in peripheral nerves, should all be leveraged towards the creation of a new generation of high-performance bionic limbs. These technologies have been clinically tested in humans, and alongside mechanical redesigns and adequate rehabilitation training should facilitate the wider clinical use of bionic limbs., This Perspective argues that technologies for the neural interfacing of robotic devices with the body that have been clinically tested in humans should be leveraged toward the creation of a new generation of high-performance bionic limbs.

Activation of peripheral nervous system (PNS) fibres to produce variable tactile and proprioceptive sensations in advanced bidirectional prosthetic limbs relies on neural stimulators with high spatial selectivity, dynamic range and resolution. A multi-channel application-specific integrated circuit (ASIC) is developed for PNS fibre activation using a wide dynamic range (10 nA-5 mA), high-resolution (30 nA step, 100 ns pulse accuracy) current stimulator, dissipating 0.73-2.75 mW at 3 V. The ASIC also enables encoding of external pressure signals

Although weight transfer is an important component of gait rehabilitation, the biomechanical strategy underlying the vertical ground reaction force loading/unloading in individuals with unilateral transfemoral amputation between intact and prosthetic limbs remains unclear. We investigated weight transfer between limbs at different walking speeds in 15 individuals with unilateral transfemoral amputation and 15 individuals without amputation as controls, who walked on an instrumented treadmill. The normalized unloading and loading rates were calculated as the slope of decay and rise phase of the vertical ground reaction force, respectively. We performed linear regression analyses for trailing limb’s unloading rate and leading limb’s loading rate between the prosthetic, intact, and control limbs. While loading rate increased with walking speed in all three limbs, the greatest increase was observed in the intact limb. In contrast to the other limbs, the prosthetic limb unloading rate was relatively insensitive to speed changes. Consequently, the regression line between trailing prosthetic and leading intact limbs deviated from other relationships. These results suggest that weight transfer is varied whether the leading or trailing limb is the prosthetic or intact side, and the loading rate of the leading limb is partially affected by the unloading rate of the contralateral trailing limb.

When nerves are damaged by trauma or disease, they are still capable of firing off electrical command signals that originate from the brain. Furthermore, those damaged nerves have an innate ability to partially regenerate, so they can heal from trauma and even reinnervate new muscle targets. For an amputee who has his/her damaged nerves surgically reconstructed, the electrical signals that are generated by the reinnervated muscle tissue can be sensed and interpreted with bioelectronics to control assistive devices or robotic prostheses. No two amputees will have identical physiologies because there are many surgical options for reconstructing residual limbs, which may in turn impact how well someone can interface with a robotic prosthesis later on. In this review, we aim to investigate what the literature has to say about different pathways for peripheral nerve regeneration and how each pathway can impact the neuromuscular tissue’s final electrophysiology. This information is important because it can guide us in planning the development of future bioelectronic devices, such as prosthetic limbs or neurostimulators. Future devices will primarily have to interface with tissue that has undergone some natural regeneration process, and so we have explored and reported here what is known about the bioelectrical features of neuromuscular tissue regeneration.

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We investigated the control of upright standing in individuals with unilateral transtibial amputation (TTA) by assessing the inter-limb coupling and the coupling between the center of pressure beneath both limbs combined (COP(NET)) and the center of pressure (COP) beneath the prosthetic limb and the intact limb. Twenty-one adults with TTA and eighteen unimpaired adults completed 90 seconds of standing on two parallel force plates. The inter-limb coupling and the coupling between the COP beneath each limb and the COP(NET) were assessed by quantifying the synchronization of the COP signals. This included the number of epochs with synchronized signals, the total duration of signal synchronization and the relative phase and deviation phase between the signals. Additionally, magnitude and temporal characteristics of the COP displacements were quantified. Individuals with TTA exhibited less COP-coupling synchronization in the anterior-posterior direction, characterized by more shifts between epochs with synchronized signals, shorter total duration of signal synchronization, less in-phase coordination patterns and a higher deviation phase between the two limbs, compared to unimpaired individuals. This coincided with a larger and more irregular postural sway in the TTA group. No group difference was observed in the mediolateral direction. The coupling between the COP(NET) and the COP beneath the individual limbs was similarly direction dependent, and tighter for the intact side, suggesting that an intact limb-driven strategy was utilized.

Lower limb amputees experience gait impairments, in part due to limitations of prosthetic limbs and the lack of a functioning biarticular gastrocnemius (GAS) muscle. Energy storing prosthetic feet restore the function of the soleus, but not GAS. We propose a transtibial prosthesis that implements a spring mechanism to replicate the GAS. A prototype Biarticular Prosthesis (BP) was tested on seven participants with unilateral transtibial amputation. Participants walked on an instrumented treadmill with motion capture, first using their prescribed prosthesis, then with the BP in four different spring stiffness conditions. A custom OpenSim musculoskeletal model, including the BP, was used to estimate kinematics, joint torques, and muscle forces. Kinematic symmetry was evaluated by comparing the amputated and intact angles of the ankle, knee, and hip. The BP knee and ankle torques were compared to the intact GAS. Finally, work done by the BP spring was calculated at the ankle and knee. There were no significant differences between conditions in kinematic symmetry, indicating that the BP performs similarly to prescribed prostheses. When comparing the BP torques to intact GAS, higher spring stiffness better approximated peak GAS torques, but those peaks occurred earlier in the gait cycle. The BP spring did positive work on the knee joint and negative work on the ankle joint, and this work increased as BP spring stiffness increased. The BP has the potential to improve amputee gait compensations associated with the lack of biarticular GAS function, which may reduce their walking effort and improve quality of life.

The 3D printing technology started and developed at the early stages of the eighties, where it is based on constructing the object layer by layer by using the appropriate material and technology and where it helps in producing a physically real object through a digital transformation process. Using 3D printing technology has many benefits, especially in the medical sector, where it could be used for speeding up the surgical operation, replacing human organs, to manufacture customized prosthetic limbs, a wide range of the material that can be used, customized designs that can be implemented since the anatomy of any person is unique and this means the geometry and dimensions of anyone bone are different from anyone else, producing surgical tools and instrumentation like jigs that can be used by the surgeon to position the implant correctly. In this chapter, the innovation of using 3D printing technology is addressed and elaborated to tackle the rapid progress and development in this sector.

Though prosthetic limbs controlled with brain–machine interfaces have the potential to confer to patients with tetraplegia the ability to physically interact with the world and regain a level of independence, the dexterity of prosthetic hands is severely limited without sensory feedback. Current brain–machine interfaces can decode motor intent from the brain remarkably well, but movements of brain-controlled anthropomorphic limbs remain slow and clumsy, in part due to this lack of somatosensory feedback. Accordingly, efforts are underway to restore tactile sensation to improve the dexterity of prosthetic limbs. Restoration of touch can also promote embodiment, the integration of the limb into the user’s sense of self. Electrical stimulation of somatosensory cortex evokes sensations of touch and can be used to convey information about interactions with objects, but our ability to shape the artificial percept is impeded by an inadequate understanding of the features of stimulation that affect sensation. To date, attempts to restore the sense of touch through intracortical microstimulation (ICMS) used either arbitrary mappings between touched objects and stimulation patterns, which took months to interpret and use, or monotonic mappings between contact force and stimulation amplitude, which led to improved performance. However, even with this feedback, dexterity does not match that of our native hands. Recent results from sensory restoration through nerve stimulation suggest that more natural feedback is associated with better performance in functional tasks. To achieve ever more naturalistic ICMS-based feedback requires that we develop our understanding of how ICMS parameters such as pulse charge, pulse patterning, and stimulation location shape the evoked sensations.

Poor wound healing following a major lower limb amputation can result in poor rehabilitation outcomes, which can be further worsened if the patient has recurrent falls and stump trauma during the wound healing stage. Direct trauma to the stump can result in bony fractures at the margins of the residual bones, and loose bony fragments may form inside the stump. These bony fragments can hinder the process of stump wound healing and interfere with prosthetic limb use and rehabilitation.

During every waking moment, we must engage with our environments, the people around us, the tools we use, and even our own bodies to perform actions and achieve our intentions. There is a spectrum of control that we have over our surroundings that spans the extremes from full to negligible. When the outcomes of our actions do not align with our goals, we have a tremendous capacity to displace blame and frustration on external factors while forgiving ourselves. This is especially true when we cooperate with machines; they are rarely afforded the level of forgiveness we provide our bodies and often bear much of our blame. Yet, our brain readily engages with autonomous processes in controlling our bodies to coordinate complex patterns of muscle contractions, make postural adjustments, adapt to external perturbations, among many others. This acceptance of biological autonomy may provide avenues to promote more forgiving human-machine partnerships. In this perspectives paper, we argue that striving for machine embodiment is a pathway to achieving effective and forgiving human-machine relationships. We discuss the mechanisms that help us identify ourselves and our bodies as separate from our environments and we describe their roles in achieving embodied cooperation. Using a representative selection of examples in neurally interfaced prosthetic limbs and intelligent mechatronics, we describe techniques to engage these same mechanisms when designing autonomous systems and their potential bidirectional interfaces.

The socket is an integral and important part of the prosthetic limb, providing link between body and technology. The quality of this connection must be considered as we strive towards embodiment of the prosthetic limb. The purpose of the socket is not just to provide a container for the residual limb but to provide a vessel where biomechanical forces can be transmitted from the body to the prosthetic componentry in the most energy -efficient manner while protecting the underlying tissues. The residual limb consists of bone surrounded by an envelope of soft tissues, including muscles which may no longer have insertion points. As the bone is able to move within the envelope of soft tissues, poor transmission of force and discomfort within the prosthesis can occur. Stabilising tissues to minimise bone movement within the socket is considered one of the primary goals in designing and constructing a well-fitting socket.

Biomechatronics (bionics) is an applied science that is interdisciplinary between biology and engineering (mechanical, electrical and electronics engineering). Biomechatronics covers a wide area and is probably best known in development of prosthetic limbs, vision aids, robotics and neuroscience. Although the gastrointestinal tract is difficult to study, it is particularly suited for a bionics approach as demonstrated by recent developments. Ingestible capsules that travel the tract and record physiological variables have been used in the clinic. Other examples include sacral nerve stimulators that seek to restore normal anorectal function. Recently, we developed a simulated stool termed fecobionics. It has the shape of normal stool and records a variety of parameters including pressures, bending (anorectal angle) and shape changes during colonic transit and defecation, i.e. it integrates several current tests. Fecobionics has been used to study defecation patterns in large animals as well as in humans (normal subjects and patient groups including patients with symptoms of obstructed defecation and fecal incontinence). Recently, it was applied in a canine colon model where it revealed patterns consistent with shallow waves originating from slow waves generated by the interstitial cells of Cajal. Furthermore, novel analysis such as the rear-front pressure (preload-afterload) diagram and quantification of defecation indices have been developed that enable mechanistic insight. This paper reviews the fecobionics technology and outlines perspectives for future applications.

Prosthetic limbs are an extension of the human body and should allow for the same function and control that a natural limb provides. Most prosthetics aim to allow an individual to return to a baseline quality of life, but few allow the individual to return to sports. Sport prosthetics can be difficult to produce due to the specificity of the designs and associated costs. Some prosthetics are becoming more accessible with the availability of 3D-printing. In this work, we create a prototype basketball prosthetic hand to enable a more natural shot. This prototype uses 3D printed springs for energy return and 3D printed electronics for integrated strain sensing that can be mapped to haptic feedback for the user. Combining these technologies will lead to a sport prosthetic limb whose technology advancements can be applied to future prosthetic designs.

Electromyography (EMG) signal is one of biological signals, it has been used in rehabilitation and prosthesis for several decades. For the control of prosthetic hands, EMG signals are usually used to make classification to recognize hand gestures or wrist motion patterns, but most research neglect the continuous motion of wrist, as a result, those prosthetic hands can't move continuously as user's intention. In this study, we proposed a novel method based on long short-term memory (LSTM) to predict continuous wrist joint torque from EMG signal. Five healthy subjects participated in the experiment, subjects were asked to flex or extend their wrist with load in their hand to simulate daily scene in life, at the same time, wrist joint angle and EMG signals were recorded synchronously. Then filtering the raw EMG to get useful components, and three time-domain features were extracted from the pre-processed EMG signals, after that reference wrist joint torque were calculated from the wrist joint motion dynamic model. At last, a wrist joint torque prediction model was established based on LSTM, and Pearson correlation coefficient between the predicted result and reference wrist joint torque was used to evaluate the performance of the proposed method. The Pearson correlation coefficient of all subjects range from 0.8669 to 0.9772, and 0.9289 on average which means the proposed wrist torque prediction model can well predict wrist torque. The proposed method can be used in the control of prosthetic limb to move continuously.

Methods used to assess quiet standing in unilateral prosthesis users often assume validity of an inverted pendulum model despite this being shown as invalid in some instances. The aim of the current study was to evaluate the validity of a proposed unilaterally-constrained pin-controller model in explaining postural control in unilateral prosthesis users. Prosthesis users were contrasted against the theoretical model as were able-bodied controls that stood on a platform which unilaterally constrained movement of the CoP. All participants completed bouts of quiet standing with eyes open, eyes closed and with feedback on inter-limb weight bearing asymmetry. Correlation coefficients were used to infer inverted pendulum behavior in both the anteroposterior and mediolateral directions and were derived from both kinematic (body attached markers) and kinetic (centre of pressure) experimental data. Larger, negative correlation coefficients reflected better model adherence, whilst low or no correlation reflected poorer model adherence. Inverted pendulum behavior derived from kinematic data, indicated coefficients of high magnitude in both mediolateral (all cases range 0.71–0.78) and anteroposterior (0.88–0.91) directions, irrespective of groups. Inverted pendulum behavior derived from kinetic data in the anteroposterior direction indicated validity of the model with large negative coefficients associated with the unconstrained/intact limbs (prosthesis users: − 0.45 to − 0.65, control group: − 0.43 to − 0.72), small coefficients in constrained/prosthetic limbs (prosthesis users: − 0.02 to 0.07, control group: 0.13–0.26) and large negative coefficients in combined conditions (prosthesis users: − 0.36 to − 0.56, control group: − 0.71 to − 0.82). For the mediolateral direction, coefficients were negligible for individual limbs (0.03–0.17) and moderate to large negative correlations, irrespective of group (− 0.31 to − 0.73). Data suggested both prosthesis users’ and able-bodied individuals’ postural control conforms well to that predicted by a unilaterally-constrained pin-controller model, which has implications for the fundamental control of posture in transtibial prosthesis users.

Sensory feedback in upper limb amputees is crucial for improving movement decoding and also to enhance embodiment of the prosthetic limb. Recently, an increasing number of invasive and noninvasive solutions for sensory stimulation have demonstrated the capability of providing a range of sensations to upper limb amputees. However, the cortical impact of restored sensation is not clearly understood. Particularly, understanding the cortical connectivity changes at multiple scales (nodal and modular) in response to sensory stimulation, can reveal crucial information on how amputees brain process the sensory stimuli. Using Electroencephalography (EEG) signals, we compared the cortical connectivity network in response to sensory feedback provided by targeted transcutaneous electrical nerve stimulation (tTENS) in an upper limb amputee during phantom upper limb movements. We focused our cortical connectivity analysis on four functional modules comprising of 20 brain regions that are primarily associated with a visually guided motor task (visual, motor, somatosensory and multisensory integration (MI)) used in this study. At the modular level, we observed that the hubness (a graph theoretic measure quantifying the importance of brain regions in integrating brain function) of the motor module decreases whereas that of the somatosensory module increases in presence of tTENS feedback. At the nodal level, similar observations were made for the visual and MI regions. This is the first work to reveal the impact of sensory feedback at multiple scales in the cortex of amputees in response to sensory stimulation.

Transfemoral prosthetic users have motor functional impairments during running. A major impairment is unintended prosthetic knee flexion during weight bearing on the prosthetic side. Therefore, the present study aims to develop a passive mechanism for a transfemoral prosthetic knee to prevent flexion during the prosthetic stance phase. The proposed mechanism has a single axis for prosthetic knee flexion–extension. The shaft that functions as the prosthetic knee joint axis can move 3 mm along the long axis of the shank part to change functions between the stance and the swing phase. The prosthetic knee joint limits only flexion and allows extension possible during the stance phase. However, it rotates freely (flexion–extension) during the prosthetic swing phase. These functions of the proposed mechanism were verified using a rough prototype. The he participant with the attached prosthetic limb prototype performed level walking with habitual gait velocity on a 10 m straight walkway. The result shows that the kinematic data of the hip, knee, and ankle were similar to able-bodied gait. Moreover, the mechanism was able to mechanically limit only the flexion with compression force acting along the shank part. These proposed mechanisms and results of the preliminary trial suggest that transfemoral amputees can run safely.

The governance of security in fields typified by emerging technologies is a complex and uncertain task. The very nature of an emerging technology means that its success as an innovation, as well as its implementation, dissemination and use, are highly speculative, as are the potential security threats or opportunities that it may present. Using the case study of the development of neuroprosthetics, a highly innovative yet experimental form of prosthetic limb that connects into nerve and muscle tissue, this chapter will explore how insights from science and technology studies concerned with managing risk and uncertainty can inform governance in areas of emerging technology. This chapter will demonstrate that existing legal frameworks are not well suited to providing governance solutions, and that instead a form of experimentalist governance based in principles of responsible research and innovation, allowing for organic and iterative forms of governance based on the interaction between knowledge and expertise provided by scientific researchers engaging with policy makers, agencies and civil society organisations are likely to be the norm until a technology is effectively realized and implemented – only then can more concrete governance structures be developed, as the lacunae of knowledge, certainty and appropriateness of response are bridged.

BACKGROUND: The bottleneck in upper limb prosthetic design is the myoelectric control algorithm. Here we studied the clinical readiness of the myoelectric postural control algorithm in a laboratory setting with two trans-radial amputees using a commercially available prosthetic limb system. TECHNIQUE: The postural control algorithm was integrated into prosthetic limb systems using standard of care components. A comparison between a commercial state of the art system (the i-limb revolution state-based myoelectric controller) and the postural controller was performed with two people with trans-radial amputation using a self-contained prosthesis system. DISCUSSION: The performance using the i-limb revolution state-based controller versus the postural controller was mixed based on the Southampton Hand Assessment Procedure. The SHAP scores indicate that the postural controller with i-limb revolution provided an average of 66% of hand function compared to an intact limb. Future work will study the advantages of the postural control algorithm in everyday use.

Robotic prostheses provide new opportunities to better restore lost functions than passive prostheses for trans-femoral amputees. But controlling a prosthesis device automatically for individual users in different task environments is an unsolved problem. Reinforcement learning (RL) is a naturally promising tool. For prosthesis control with a user in the loop, it is desirable that the controlled prosthesis can adapt to different task environments as quickly and smoothly as possible. However, most RL agents learn or relearn from scratch when the environment changes. To address this issue, we propose the knowledge-guided Q-learning (KG-QL) control method as a principled way for the problem. In this report, we collected and used data from two able-bodied (AB) subjects wearing a RL controlled robotic prosthetic limb walking on level ground. Our ultimate goal is to build an efficient RL controller with reduced time and data requirements and transfer knowledge from AB subjects to amputee subjects. Toward this goal, we demonstrate its feasibility by employing OpenSim, a well-established human locomotion simulator. Our results show the OpenSim simulated amputee subject improved control tuning performance over learning from scratch by utilizing knowledge transfer from AB subjects. Also in this paper, we will explore the possibility of information transfer from AB subjects to help tuning for the amputee subjects.

BACKGROUND: Small residual limb-socket displacement is a good indicator of prosthetic suspensionsystem quality. Active vacuum suspension systems can decrease vertical movement inside the socket,compared to non-active suction systems. This study mechanically evaluated limb-socket displacementwith the Össur Unity active vacuum system. METHOD: Forty-eight conditions were evaluated: four cylindrical and four conical sockets(polypropylene, polyethylene terephthalate glycol-modified (PETG), thermoset resin (acrylic),Thermolyn soft materials); two Iceross Seal-In V liners (standard, high profile); three vacuumconditions (active vacuum, inactive vacuum, no suction with valve open). An Instron 4428 test machineapplied 0-100N linear ramped tensile loads to each positive mold, with the socket secured in place,while displacement between the mold and socket was recorded. Following the displacement tests, theload before failure (i.e., 10 mm displacement) was measured. RESULTS: Average and standard deviations for movement between the mold and sockets were small.The displacement average for all conditions was 0.30±0.16mm for active vacuum, 0.32±0.16mm forinactive vacuum, and 0.39±0.22mm for no suction. Across all trials, active vacuum systems toleratedsignificantly (p

During last few years, development of bipedal robot has been increased in very rapid way. In this paper, we have tried to explain different Computational models from engineering viewpoints which helps us to understand Human Gait and the same is applied to bipedal robots for effective and fast, energy efficient walking. This involves from very basic models to large scale computational models for bipedal walking much like human being and tendency to regain original state if some external force is applied. This paper explains the historical journey of bipedal robots that can walk almost similar to human being. Paper further explores the possible research areas in bipedal robots walking and ways to balance bipedal robot against external forces like push recovery. Gait is used in Human recognitions, biometrics and to develop prosthetic limbs for physically disabled persons.

Summary:. Painful neuromas result from traumatic injuries of the hand and digits and cause substantial physical disability, psychological distress, and decreased quality of life among affected patients. The regenerative peripheral nerve interface (RPNI) is a novel surgical technique that involves implanting the divided end of a peripheral nerve into a free muscle graft for the purposes of mitigating neuroma formation and facilitating prosthetic limb control. The RPNI is effective in treating and preventing neuroma pain in major extremity amputations. The purpose of this study was to determine if RPNIs can be used to effectively treat neuroma pain following partial hand and digital amputations. We retrospectively reviewed the use of RPNI to treat symptomatic hand and digital neuromas at our institutions. Between November 2014 and July 2019, we performed 30 therapeutic RPNIs on 14 symptomatic neuroma patients. The average patient follow-up was 37 weeks (6–128 weeks); 85% of patients were pain-free or considerably improved at the last office visit. The RPNI can serve as a safe and effective surgical solution to treat symptomatic neuromas after hand trauma.

Revolutionizing Prosthetics is a government-sponsored program focused on maturing the many foundational technologies that comprise neural prosthetic systems. Targeting the needs of amputees and movement-impaired individuals, the program focused on technological advancements in areas such as advanced neural recording devices, neural decoding and encoding algorithms, and upper limb prosthetic systems. A primary objective of the program was to support technological advancement of wearable prosthetic devices at the upper limb and hand level. The Modular Prosthetic Limb (MPL) is a representation of the vision for a highly anthropometric prosthetic limb. With 26 articulating joints, 17 actuators, and hundreds of internal sensors for feedback, the vision of the MPL was to replicate the dexterity, speed, and strength of the human hand to an extent never realized in a prosthetic device. Here we describe the MPL’s evolution over the past 13 years and describe the system in entirety, focusing on the fundamental characteristics of the system from hardware to software and controls. Additionally, we briefly touch upon some clinical applications and alternative use cases for the system to date.

Sport with a disability has progressed from undertaking physical activity for recreation to one of a high performance environment at competitions such as the Paralympic Games. There is currently limited information and guidance to help inform stakeholders as to how to develop the high performance technology of elite athletes who possess limb absence. In this manuscript, a conceptual framework for high performance prosthetic limb creation is presented. This utilises a synthesis between contemporary product design theory and a review of existing case studies. This proposed framework is then applied to a case study. Ultimately, the framework provides an indicative guide to the creation of prosthetic limbs that emphasise technological performance enhancement over that of mere sporting participation.

Innovative prostheses are generating new possibilities for artists, performers and athletes with adaptive bodies. Performers, such as Aimee Mullins working with Alexander McQueen and Matthew Barney, and Viktoria Modesta working with Sophie de Oliveira Barata of The Alternative Limb Project, are leading the way in exploring an emerging terrain of unreal prosthetic limbs. This chapter compares this world of surreal prosthetic limbs to the drawing game ‘Exquisite Corpse’ invented in Paris in 1925 by the Surrealist artists Andre Breton, Marcel Duchamp, Yves Tanguy and Jacques Prevert, in the way they both raise powerful questions as to the boundaries of the human body and the interrelationship between the corporeal and the non-corporeal. In 2014 Erin Ball, the Canadian Contemporary Circus artist, after suffering severe frostbite, had both of her lower legs amputated. This chapter follows her in her determination to re-imagineer her adaptive body and to explore the world of surreal prosthetic limbs in Contemporary Circus performance. The writing also explores the emerging collaboration between Erin Ball and Kristina Walsh, a Canadian prosthetics designer, currently Artist in Residence at the Sarabande Studios which are run by the Alexander McQueen Foundation in London.

The incidence of blast injuries is increasing, in both the civilian and combat settings. Heterotopic ossification (HO), the aberrant growth of bone outside of the skeleton, is a common complication as a consequence of these injuries. HO can cause chronic pain and skin ulceration and prevent prosthetic limb fitting, significantly delaying rehabilitation in these patients. Current preventions, which were developed for HO formed following hip surgery, show inconsistent efficacy and side effects that make them intolerable for patients with high-energy injuries. This leaves surgical excision as the only available treatment. The biological processes behind HO are complex, with several cell types able to differentiate down HO tissue lineages, and it is likely that several pathways exist concurrently. However, as the biological mechanisms are becoming clearer, new targets are being identified and novel drugs developed for HO prophylaxis. The goal of these advances is to provide new therapies to prevent HO and improve the quality of life for blast-injured patients.

In the last two decades, osseointegrated prostheses have been shown to be a good alternative for lower limb amputees experiencing complications in using a traditional socket-type prosthesis, however, restraining biomechanical issues, such as peri-prosthetic bone fractures or loosening, are present. To better understand and overcome these limiting issues, and thus reduce the number of implant failures, many studies have investigated the stress distribution on bone and implant during normal daily activities. The aim of this study was a biomechanical analysis of two different osseointegrated implants, a screw-type (OPRA) and a press fit system (OPL, Osseointegrated Prosthetic Limb), to evaluate the stresses generated in bone and prosthesis during a fall. In particular, four scenarios have been experimentally reproduced to determine the loads on the limb during different kinds of fall. For this purpose, a motion capture system and a force plate have been used. Numerical FEM (Finite Element Method) simulations have been performed to compare the behaviour of the OPRA and OPL systems in different fall scenarios. The obtained results showed that a fall backwards due to balance loss is the most stressful scenario among the ones analysed. As regards the comparison between OPRA and OPL devices, it emerged they have similar behaviours in terms of peak values of the stress, but the OPL implant generates larger high-stress areas in the distal femur as compared with the OPRA system.

Taking the advantages offered by smart high-performance electronic devices, transradial prosthesis for upper-limb amputees was developed and tested. It is equipped with sensing devices and actuators allowing hand movements; myoelectric signals are detected by Myo armband with 8 ElectroMyoGraphic (EMG) electrodes, a 9-axis Inertial Measurement Unit (IMU) and Bluetooth Low Energy (BLE) module. All data are received through HM-11 BLE transceiver by Arduino board which processes them and drives actuators. Raspberry Pi board controls a touchscreen display, providing user a feedback related to prosthesis functioning and sends EMG and IMU data, gathered via the armband, to cloud platform thus allowing orthopedic during rehabilitation period, to monitor users’ improvements in real time. A GUI software integrating a machine learning algorithm was implemented for recognizing flexion/extension/rest gestures of user fingers. The algorithm performances were tested on 9 male subjects (8 able-bodied and 1 subject affected by upper-limb amelia), demonstrating high accuracy and fast responses.

Human beings are poorly adapted to live and work in space for long periods of time. This situation poses as yet insurmountable challenges for deep space travel and the colonisation of other worlds including those in our solar systems such as the Moon or Mars. Research road maps have been built by multi-disciplinary teams working internationally to explore the development of artificial gravity and protection of the body against radiation including the potential for human enhancement by techniques such as gene editing. Terrestrial technological advances in the development of prosthetic limbs and tissue-engineered organs which may be accompanied by the production of exoskeletal structure offer further opportunities for human augmentation. Finally, progress in the generation of brain–computer interface-based communication systems in patients who are unable to communicate may offer more futuristic applications for building a society of hybrid human avatars as future colonists of New World civilisations.

Background Transtibial hydrocast sockets have been shown to be a potential alternative to hand-cast patella-tendon bearing sockets, the use of which would have particular benefits in under-resourced environments. However, data concerning wearer outcomes of hard hydrocast sockets (i.e. those without silicone liners), especially over long-term usage periods, is scarce in the literature. Research questions Are there any changes in wearer functional, spatio-temporal or satisfaction outcomes over a long usage period with a hydrocast socket? And how do the post-usage period outcomes compare with those from the wearers original prostheses? Methods In this pre-post interventional study, the clinical outcomes of twenty-one experienced transtibial prostheses users were evaluated using widely-accepted and employed methods to assess wearer functional capacity, mobility, gait and satisfaction. The participants were fit with a hard hydrocast socket and the outcomes after an extensive usage period of 5 months were compared to the pre-usage period data following initial fitting and the data collected from the participants’ original prosthetic limb. Results Significant differences were found in the temporal parameters of gait, all indicating decreased reliance on the intact limb and an increased loading of the prosthetic limb with the post-usage period hydrocast socket compared to both the pre-usage period socket and the participants’ original limbs. No differences in the functional capacity, mobility, spatial gait parameters or satisfaction were found between the socket conditions. Significance This is the largest study to date of functional, spatio-temporal and satisfaction outcomes of hydrocast sockets following an extended usage period in an under-resourced environment.

Use of elastomeric or “gel” liners in prosthetics practice has become increasingly common, with recent data suggesting that practitioners select gel liners for about 85% of their prosthetic patients.1 To accommodate the clinical needs of a broad range of prosthetic limb users, liner manufacturers have created an array of different liner products. Although elastomeric liners are derived primarily from the same base materials (i.e., urethane, silicone, and thermoplastic elastomer (TPE]), differences in a liner’s chemical composition, shape, geometry, and manufacturing determine a liner’s overall performance. Presence of fabric backing, antibacterial additives, or features such as sealing sleeves, distal pads, or reinforcement can additionally affect mechanical performance of a liner. Given the number of variables that contribute to a liner’s design, it is not surprising that a large number of liner products are commercially available – a recent study identified more than 70 liner products on the market.2 Despite the availability of so many different liner products, a recent survey indicated that a typical practitioner choses among only two or three products when selecting liners for his or her prosthetic patients.2 An explanation for such limited selection among many available options may be a lack of comparable, objective information about the similarities and differences among liner products.3 Without information about how a new liner compares to the two or three familiar products, practitioners are hesitant to change. The same study found that only 33% of practitioners surveyed obtained information from scientific journals, while the majority sought information directly from manufacturers (94%) or clinical magazines (65%). These results suggest there is a need to distinguish liners and provide practitioners with practical information to help them identify products that best match individual patient needs. The purpose of this research study was to characterize mechanical properties of commonly used prosthetic liner products and to compare findings with previous liners characterized in the literature. We also evaluated the influence of design variables fabric backing and liner thickness on testing results. Selecting a liner for an individual patient may require the practitioner optimize the most preferred property or identify a liner that exhibits a balance among several preferred properties.

We review the latest innovations and functional results in prosthetic limb design and function. Bionic prostheses, computer-aided design software applications, 3D scanners, automated carving machines, are recent innovations in limb designs. Recent advances in the development of bionic prostheses, computer-aided design software applications, 3D scanners, automated carving machines, as well as the development of measuring and alignment devices that allow us the placement, orientation, adjustment, and adaptation of prosthesis to the particular conditions of the user, in a biomechanically correct manner, have meant a definitive leap towards an improvement in the quality of life. The application of new technologies such as 3D printing is proposed as an alternative to reduce costs. We discuss here both the current advances in bioelectric prostheses, their benefits and advantages, and the applications of 3DP in clinical practice.

This review focuses on the options that are available for people who have had below and above knee amputations. Prosthetic limbs have evolved, with substantial technological advancements in the past two decades. However, the most sophisticated device is not the most appropriate for everyone. Osseointegration appears to have become an established treatment option for a selected group of patients with limb amputation. However, there is sufficient evidence to fully inform patients as to the possible risks and complications compared with the benefits. The active prostheses clinical research is limited to prototypes and low number of subjects, although test results show the potential to restore the functional performance of an amputee. This review article highlights the prosthetic options that are available for people who have had below and above knee amputations. The development of osseointegration and active prostheses is a challenging task and thus should remain subject to future research including extended clinical evaluations.

In a best-selling book series by Cressida Cowell, Fishlegs is a Viking runt—a weak baby cast on the oceans for the gods to decide his fate. He is skinny, has asthma and eczema, wears broken glasses, and is clumsy. On screen, he is non-disabled (though overweight), and appears with several likeable characters who have prosthetic limbs, including the anti-hero Hiccup; the villain Alvin is now non-disabled. In later books, Cowell utilizes notions of the marked body and stigma as prisoners are branded with an S-shaped “Slavemark.” When Hiccup’s mark is discovered he is rejected by his tribe, but later his S-shaped brand becomes a “Dragonmark” and rousing rhetoric from Hiccup and his mother has similarities to reclamation words and acts within the disability rights movement. Although the writer makes a liberal case for the inclusion of “outsiders” and a strong case to end the stigma of slavery, the true outsider status of the impaired Fishlegs and Alvin is ignored.

Walking down ramps is a demanding task for transfemoral-amputees and terminating gait on ramps is even more challenging because of the requirement to maintain a stable limb so that it can do the necessary negative mechanical work on the centre-of-mass in order to arrest (dissipate) forward/downward velocity. We determined how the use of a microprocessor-controlled limb system (simultaneous control over hydraulic resistances at ankle and knee) affected the negative mechanical work done by each limb when transfemoral-amputees terminated gait during ramp descent.Eight transfemoral-amputees completed planned gait terminations (stopping on prosthesis) on a 5-degree ramp from slow and customary walking speeds, with the limb's microprocessor active or inactive. When active the limb operated in its 'ramp-descent' mode and when inactive the knee and ankle devices functioned at constant default levels. Negative limb work, determined as the integral of the negative mechanical (external) limb power during the braking phase, was compared across speeds and microprocessor conditions.Negative work done by each limb increased with speed (p 0.001), and on the prosthetic limb it was greater when the microprocessor was active compared to inactive (p = 0.004). There was no change in work done across microprocessor conditions on the intact limb (p = 0.35).Greater involvement of the prosthetic limb when the limb system was active indicates its ramp-descent mode effectively altered the hydraulic resistances at the ankle and knee. Findings highlight participants became more assured using their prosthetic limb to arrest centre-of-mass velocity.

Background Daily ambulation with a prosthesis often involves turning to negotiate within the home and community environments, however how people with lower limb loss perform turns is infrequently studied. Administering a common clinical outcome measure to capture turn performance data provides a convenient means of assessing this ubiquitous activity. Research question What temporal-spatial parameters are exhibited by people with unilateral lower limb amputation while performing a 180˚ turn task? Methods Forty community-ambulating subjects with unilateral lower limb amputation (20 transtibial amputees, 20 transfemoral amputees) performed the Component Timed-Up-and-Go (cTUG) test turning once in each direction, both toward the intact and toward the prosthetic limb. An instrumented walkway captured temporal-spatial parameters during performance of the 180˚ turn task of the cTUG, while a custom iPad application recorded time and number of steps to perform the turn. Comparisons between turn direction and level of amputation during the cTUG and temporal-spatial results were assessed. Results People with lower limb amputation spent more time on their intact limb while turning than their prosthetic limb regardless of the position of the intact limb, and those with transfemoral amputation spent significantly more time over the intact limb than those with transtibial amputation. Additionally, subjects with transfemoral amputation performed the turn significantly faster when turning with an inner intact limb. Significance Amputees use different movement strategies with altered temporal-spatial characteristics to turn depending on the direction of the turn and the level of amputation. Clinical use of the cTUG could provide evidence supporting prosthetic prescription practice and introduction of novel physical therapy interventions for individuals with lower limb amputation.

In human gait analysis studies, the entire foot is typically modeled as a single rigid-body segment; however, this neglects power generated/absorbed within the foot. Here we show how treating the entire foot as a rigid body can lead to misunderstandings related to (biological and prosthetic) foot function, and distort our understanding of ankle and muscle-tendon dynamics. We overview various (unconventional) inverse dynamics methods for estimating foot power, partitioning ankle vs. foot contributions, and computing combined anklefoot power. We present two case study examples. The first exemplifies how modeling the foot as a single rigid-body segment causes us to overestimate (and overvalue) muscle-tendon power generated about the biological ankle (in this study by up to 77%), and to misestimate (and misinform on) foot contributions; corroborating findings from previous multi-segment foot modeling studies. The second case study involved an individual with transtibial amputation walking on 8 different prosthetic feet. The results exemplify how assuming a rigid foot can skew comparisons between biological and prosthetic limbs, and lead to incorrect conclusions when comparing different prostheses/interventions. Based on analytical derivations, empirical findings and prior literature we recommend against computing conventional ankle power (between shank-foot). Instead, we recommend using an alternative estimate of power generated about the ankle joint complex (between shank-calcaneus) in conjunction with an estimate of foot power (between calcaneus-ground); or using a combined anklefoot power calculation. We conclude that treating the entire foot as a rigid-body segment is often inappropriate and ill-advised. Including foot power in biomechanical gait analysis is necessary to enhance scientific conclusions, clinical evaluations and technology development.

Purpose: To develop a valid preoperative scoring tool that predicts the probability of walking with a prosthetic limb after major lower limb amputation.Methods: A retrospective review of 338 patien...

The damping characteristic of a healthy limb changes throughout the gait cycle. However, for amputees who are wearing mechanically passive damping prosthesis, the lack of ability to change the damping values might expose them to injuries and health problems. The use of magnetorheological fluid damper in prosthetic limb, which provides wide dynamic range, seems to be able to prevent these conditions from happening, due to its response to the magnetic field. The magnetorheological fluid, a type of smart material that is capable of altering its rheological property, changes its viscosity subjected to the intensity of the external magnetic field. Thus, due to this property, magnetorheological fluid damper covers the advantages of both passive and active dampers. This work explores the implementation of magnetorheological fluid damper in transtibial (below knee) prosthetic limb utilizing adaptive control techniques via simulation studies. An experimental study was done to observe the relationship of the force generated by the damper to the applied current. In addition, fuzzy-proportional–integral–derivative controller was implemented to ensure that the damper performs well, even at varying frequencies.