31 research outputs found
Advances in Propulsive Bionic Feet and Their Actuation Principles
No full textIn the past decades, researchers have deeply studied pathological and nonpathological gait to understand the human ankle function during walking. These efforts resulted in the development of new lower limb prosthetic devices aiming at raising the 3C-level (control, comfort, and cosmetics) of amputees. Thanks to the technological advances in engineering and mechatronics, challenges in the field of prosthetics have become an important source of interest for roboticists. Currently, most of the bionic feet are still on a research level but show promising results and a preview of tomorrow's commercial prosthetic devices. In this paper, the authors present the current state-of-the-art and the latest advances in propulsive bionic feet with its actuation principles. The context of this review study is outlined followed by a brief description of the basics in human biomechanics and criteria for new prosthetic designs. A new categorization based on the actuation principle of propulsive ankle-foot prostheses is proposed. Based on simulations, the general principles and benefits of each actuation method are explained. The corresponding latest advances in propulsive bionic feet are presented together with their main characteristics and scientific outcomes. The authors also propose to the reader a comparison analysis of the presented devices with a discussion of the general tendencies in new prosthetic feet
AMP-Foot 2.0: An Active Trans-tibial Prosthesis that Mimicks Able-Bodied Ankle Behavior
No full textTranstibial (TT) amputations are among the most frequently performed major limb removals. To replace the missing limb, numerous prosthetic devices are currently on the market. In general, prosthetic feet can be classified into three categories [1]: conventional feet (CF), ’energy-storingand-returning’ (ESR) feet and bionic feet. When studying the state-of-the-art in TT prosteses, one can conclude that passive energy storing devices (ESR feet) are energetically efficient but do not provide the extra power needed for propulsion during walking. On the other hand, actuated devices are able to provide the necessary energy, but need heavy and bulky actuators capable of producing high torques in small periods of time. Our research focuses on combining the best of both worlds. With the AMP-Foot 2.0, the author
Examining correlates of past year major depressive episode among black men and black women in the United States
No full textBackground: Depression is a major public health problem. Even though Black people are the second largest racial group in the United States, little data exists examining correlates of depression among Black adults. In addition, while attention to gender disparities in science has led to calls for gender-specific data analyses, only a handful of studies on depression have reported gender-specific findings for Black adults Methods: This study examined gender-specific risk and protective correlates of past year major depressive episodes (PY-MDE). Participants were Black men (N=1,681) and Black women (N=2,437) who participated in wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions. The risk correlates studied included ten adverse childhood experiences (ACEs), past year intimate partner violence, and past year racial and gender discrimination. The protective correlates studied were religiosity and ethnic identity. Results: Intimate partner violence was the only correlate of PY-MDE for both Black men and women. The association between intimate partner violence and PY-MDE was larger for Black men (Adjusted odds ratio (AOR) =3.03) than Black women (AOR=1.70). Childhood psychological and sexual abuse were associated with PY-MDE for Black women, but not men. Among Black women, the association between gender discrimination and PY-MDE was significant (AOR=2.21). Neither religiosity or ethnic identity were protective for Black men and women. Discussion: Findings suggest the need for gender-specific interventions for depression among Black adults that address racial and gender discrimination, IPV, and that include culturally adapted CBT and trauma informed therapy.M.A.Includes bibliographical reference
The AMP-Foot 3, new generation propulsive prosthetic feet with explosive motion characteristics: design and validation
No full textThe last decades, rehabilitation has become a challenging context for mechatronical engineering. From the state-of-the-art it is seen that the field of prosthetics offers very promising perspectives to roboticist. Today’s prosthetic feet tend to improve amputee walking experience by delivering the necessary push-off forces while walking. Therefore, several new types of (compliant) actuators are developed in order to fulfill the torque and power requirements of a sound ankle-foot complex with minimized power consumption. At the Vrije Universiteit Brussel, the Robotics and Multibody Mechanics research group puts a lot of effort in the design and development of new bionic feet. In 2013, the Ankle Mimicking Prosthetic (AMP-) Foot 2, as a proof-of-concept, showed the advantage of using the explosive elastic actuator capable of delivering the full ankle torques (
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120
Nm) and power (
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250
W) with only a 60 W motor. In this article, the authors present the AMP-Foot 3, using an improved actuation method and using two locking mechanisms for improved energy storage during walking. The article focusses on the mechanical design of the device and validation of its working principle.This work and the publication costs of this article have been funded by the European Commissions 7th Framework Program as part of the project Cyberlegs under grant no. 287894 and by the European Commission ERC Starting grant SPEAR under grant no. 337596.Peer reviewe
Vanderborght, “The amp-foot 2.0: Mimicking intact ankle behavior with a powered transtibial prosthesis
No full textAbstract — Almost all of the transtibial prostheses that are available on the market are purely passive devices. They store energy in an elastic element at the beginning of a step and release it at the end in order to move the body forward. The main problem with these prostheses is that only the energy that has been stored in the elastic element is used for the push-off, unlike for non-pathological ankles where the muscles provide extra energy. There are a few prostheses who use active components for this energy input. In this article, the authors propose a new design of an energy efficient, powered transtibial prosthesis to mimic intact ankle behaviour, the AMP-Foot 2.0. The main idea behind our research is to have the actuator work longer with a lower power rating while the produced energy is stored in elastic elements and released when needed for propulsion. The device is designed to provide 100 % of pushoff for a 75 kg subject walking at normal cadence on ground level. I
Case Study on Human Walking during Wearing a Powered Prosthetic Device: Effectiveness of the System “Human-Robot”
No full textIt is known that force exchanges between a robotic assistive device and the end-user have a direct impact on the quality and performance of a particular movement task. This knowledge finds a special reflective importance in prosthetic industry due to the close human-robot collaboration. Although lower-extremity prostheses are currently better able to provide assistance as their upper-extremity counterparts, specific locomotion problems still remain. In a framework of this contribution the authors introduce the multibody dynamic modelling approach of the transtibial prosthesis wearing on a human body model. The obtained results are based on multibody dynamic simulations against the real experimental data using AMP-Foot 2.0, an energy efficient powered transtibial prosthesis for actively assisted walking of amputees
Concept of a Series-Parallel Elastic Actuator for a Powered Transtibial Prosthesis
No full textThe majority of the commercial transtibial prostheses are purely passive devices. They store energy in an elastic element during the beginning of a step and release it at the end. A 75 kg human, however, produces on average 26 J of energy during one stride at the ankle joint when walking at normal cadence and stores/releases 9 J of energy, contributing to energy efficient locomotion. According to Winter, a subject produces on average of 250W peak power at a maximum joint torque of 125 Nm. As a result, powering a prosthesis with traditional servomotors leads to excessive motors and gearboxes at the outer extremities of the legs. Therefore, research prototypes use series elastic actuation (SEA) concepts to reduce the power requirements of the motor. In the paper, it will be shown that SEAs are able to reduce the power of the electric motor, but not the torque. To further decrease the motor size, a novel human-centered actuator concept is developed, which is inspired by the variable recruitment of muscle fibers of a human muscle. We call this concept series-parallel elastic actuation (SPEA), and the actuator consists of multiple parallel springs, each connected to an intermittent mechanism with internal locking and a single motor. As a result, the motor torque requirements can be lowered and the efficiency drastically increased. In the paper, the novel actuation concept is explained, and a comparative study between a stiff motor, an SEA and an SPEA, which all aim at mimicking human ankle behavior, is performed
Therapeutic benefits of lower limb prostheses: a systematic review
No full textAbstract Background Enhancing the quality of life of people with a lower limb amputation is critical in prosthetic development and rehabilitation. Yet, no overview is available concerning the impact of passive, quasi-passive and active ankle–foot prostheses on quality of life. Objective To systematically review the therapeutic benefits of performing daily activities with passive, quasi-passive and active ankle–foot prostheses in people with a lower limb amputation. Methods We searched the Pubmed, Web of Science, Scopus and Pedro databases, and backward citations until November 3, 2021. Only English-written randomised controlled trials, cross-sectional, cross-over and cohort studies were included when the population comprised individuals with a unilateral transfemoral or transtibial amputation, wearing passive, quasi-passive or active ankle–foot prostheses. The intervention and outcome measures had to include any aspect of quality of life assessed while performing daily activities. We synthesised the participants’ characteristics, type of prosthesis, intervention, outcome and main results, and conducted risk of bias assessment using the Cochrane risk of bias tool. This study is registered on PROSPERO, number CRD42021290189. Results We identified 4281 records and included 34 studies in total. Results indicate that quasi-passive and active prostheses are favoured over passive prostheses based on biomechanical, physiological, performance and subjective measures in the short-term. All studies had a moderate or high risk of bias. Conclusion Compared to passive ankle–foot prostheses, quasi-passive and active prostheses significantly enhance the quality of life. Future research should investigate the long-term therapeutic benefits of prosthetics devices
Concept and Design of the HEKTA (Harvest Energy from the Knee and Transfer It to the Ankle) Transfemoral Prosthesis
No full textAbstract-The main issues with the current transfemoral prostheses are the insufficient ankle plantarflexion resulting in an insufficient push-off and the lack of knee flexion during stance phase. The HEKTA (Harvest Energy from the Knee and Transfer it to the Ankle) is a prototype of a prosthesis that allows a transfemoral amputee to walk overground with a more natural gait pattern. The prototype allows knee flexion during the stance phase and harvests the energy that needs to be dissipated during the swing phase. The energy is transferred to the ankle where it provides an active push off
