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Types of amputation: (a) amputation at the hip and pelvis region, (b) transfemoral amputation, (c) amputation at the knee (knee disarticulation), (d) transtibial amputation and (e) amputation at the foot. 64
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With the recent progress in personal care robots, interest in wearable exoskeletons has been increasing due to the demand for assistive technologies generally and specifically to meet the concerns in the increasing ageing society. Despite this global trend, research focus has been on load augmentation for soldiers/workers, assisting trauma patients...
Citations
... Adjustable workstations stand as a fundamental tool, allowing workers to customize their work environment to suit their individual ergonomic needs, thereby contributing to improved comfort and reduced risk of musculoskeletal disorders (Swinton et al., 2017). Ergonomic tools such as exoskeletons have gained prominence for their ability to reduce physical strain during lifting tasks, thereby enhancing safety and comfort in industrial settings (Rupal et al., 2017). Motion analysis software, such as the Open Motion Planning Library, has been instrumental in evaluating and optimizing workplace ergonomics, particularly in the design and assessment of ergonomic solutions aimed at reducing physical strain on workers (Şucan et al., 2012). ...
This research in the Industry 5.0 field focuses on a human-centered simulation of the FAS200 SMC educational production line, utilizing Tecnomatix Process Simulate Human software for developing a virtual human environment. A key aspect of this study is the integration of inertial sensors, enhancing the accuracy and depth of ergonomic analysis. These sensors play a pivotal role in capturing precise human movement data, crucial for ergonomic assessments. Adopting a defined working methodology, the study extensively employs the RULA method to evaluate operator postures in the production line. This approach has led to significant ergonomic improvements, evidenced by a 40 percent reduction in the RULA index at each workstation. The integration of inertial sensors has been instrumental in achieving these results, providing detailed insights into human movements and interactions with the production environment. The research transcends traditional ergonomic assessments by incorporating a new human-centered approach, emphasizing the well-being of individuals working alongside machines. This approach, bolstered by the use of inertial sensors, marks a significant advancement in ergonomic studies, aligning with the principles of Industry 5.0. The findings hold substantial potential for application in industrial settings, signaling a shift towards more human-friendly and efficient industrial practices.
... Lower-limb exoskeleton robots can be classified into medical rehabilitation lower-limb exoskeletons and power-assisted lower-limb exoskeletons according to their functionality [1]. They can also be classified into medical lower-limb exoskeletons and non-medical lowerlimb exoskeletons according to the end users [2]. For the control methods of different exoskeletons, exoskeletons designed for medical applications are typically implemented through predefined gaits, whereas exoskeletons designed for non-medical applications are typically implemented through motion tracking. ...
The exoskeleton robot is a wearable electromechanical device inspired by animal exoskeletons. It combines technologies such as sensing, control, information, and mobile computing, enhancing human physical abilities and assisting in rehabilitation training. In recent years, with the development of visual sensors and deep learning, the environmental perception of exoskeletons has drawn widespread attention in the industry. Environmental perception can provide exoskeletons with a certain level of autonomous perception and decision-making ability, enhance their stability and safety in complex environments, and improve the human–machine–environment interaction loop. This paper provides a review of environmental perception and its related technologies of lower-limb exoskeleton robots. First, we briefly introduce the visual sensors and control system. Second, we analyze and summarize the key technologies of environmental perception, including related datasets, detection of critical terrains, and environment-oriented adaptive gait planning. Finally, we analyze the current factors limiting the development of exoskeleton environmental perception and propose future directions.
... Walking is an essential activity in daily life. Mobility augmentation through the use of wearable assistive ambulatory devices can provide vertical support, assist in lowerlimb motion, and improve the quality of life for users [4,[6][7][8][9][10][11][12][13][14][15]. In addition to the medical applications of wearable assistive ambulatory devices, the impact of various non-medical applications of these devices is also being realized, as they may be able to help healthy individuals perform important activities in daily life [4,5,16]. ...
... Mobility augmentation through the use of wearable assistive ambulatory devices can provide vertical support, assist in lowerlimb motion, and improve the quality of life for users [4,[6][7][8][9][10][11][12][13][14][15]. In addition to the medical applications of wearable assistive ambulatory devices, the impact of various non-medical applications of these devices is also being realized, as they may be able to help healthy individuals perform important activities in daily life [4,5,16]. While there are intricate complexities related to safety regulatory requirements, user acceptance, as well as device reliability and adaptability that need to be considered, assistive ambulatory devices have the potential to help in such situations and may even reduce the burden on healthcare resources [4]. ...
... In addition to the medical applications of wearable assistive ambulatory devices, the impact of various non-medical applications of these devices is also being realized, as they may be able to help healthy individuals perform important activities in daily life [4,5,16]. While there are intricate complexities related to safety regulatory requirements, user acceptance, as well as device reliability and adaptability that need to be considered, assistive ambulatory devices have the potential to help in such situations and may even reduce the burden on healthcare resources [4]. Nevertheless, given the importance of mobility assistance for both medical and non-medical end-user applications, there has been increasing interest in designing more effective and intelligent assistive ambulatory technologies [1,[4][5][6]8,9,11,12,[17][18][19][20][21][22][23][24][25][26][27][28][29]. ...
Smart algorithms for gait kinematic motion prediction in wearable assistive devices including prostheses, bionics, and exoskeletons can ensure safer and more effective device functionality. Although embedded systems can support the use of smart algorithms, there are important limitations associated with computational load. This poses a tangible barrier for models with increased complexity that demand substantial computational resources for superior performance. Forecasting through Recurrent Topology (FReT) represents a computationally lightweight time-series data forecasting algorithm with the ability to update and adapt to the input data structure that can predict complex dynamics. Here, we deployed FReT on an embedded system and evaluated its accuracy, computational time, and precision to forecast gait kinematics from lower-limb motion sensor data from fifteen subjects. FReT was compared to pretrained hyperparameter-optimized NNET and deep-NNET (D-NNET) model architectures, both with static model weight parameters and iteratively updated model weight parameters to enable adaptability to evolving data structures. We found that FReT was not only more accurate than all the network models, reducing the normalized root-mean-square error by almost half on average, but that it also provided the best balance between accuracy, computational time, and precision when considering the combination of these performance variables. The proposed FReT framework on an embedded system, with its improved performance, represents an important step towards the development of new sensor-aided technologies for assistive ambulatory devices.
... Therefore, in this work, one such possible solution is incorporated by placing the heavy-duty actuators on a stand such that the exoskeleton links have to bear their self-weight only. • The cost of lower limb rehabilitation devices for gait assistance typically falls within a range of US $30,000 to US $130,000 per unit, making them unaffordable for many prospective users [44]. One of the premier reasons for such high cost is the sophisticated design of lightweight actuators and drives. ...
Existing exoskeletons for pediatric gait assistance have limitations in anthropometric design, structure weight, cost, user safety features, and adaptability to diverse users. Additionally, creating precise models for pediatric rehabilitation is difficult because the rapid anthropometric changes in children result in unknown model parameters. Furthermore, external disruptions, like unpredictable movements and involuntary muscle contractions, add complexity to the control schemes that need to be managed. To overcome these limitations, this study aims to develop an affordable stand-aided lower-limb exoskeleton specifically for pediatric subjects (8-12 years, 25-40 kg, 128-132 cm) in passive-assist mode. The authors modified a previously developed model (LLESv1) for improved rigidity, reduced mass, simplified motor arrangement, variable waist size, and enhanced mobility. A computer-aided design of the new exoskeleton system (LLESv2) is presented. The developed prototype of the exoskeleton appended with a pediatric subject (age: 12 years old, body mass: 40 kg, body height: 132 cm) is presented with real-time hardware architecture. Thereafter, an improved fast non-singular terminal sliding mode (IFNSTSM) control scheme is proposed, incorporating a double exponential reaching law for expedited error convergence and enhanced stability. The Lyapunov stability warrants the control system's performance despite uncertainties and disturbances. In contrast to fast non-singular terminal sliding mode (FNSTSM) control and time-scaling sliding mode (TSSM) control, experimental validation demonstrates the effectiveness of IFNSTSM control by a respective average of 5.39% and 42.1% in tracking desired joint trajectories with minimal and rapid finite time converging errors. Moreover, the exoskeleton with the proposed IFNSTSM control requires significantly lesser control efforts than the exoskeleton using contrast FNSTSM control. The Bland-Altman analysis indicates that although there is a minimal mean difference in variables when employing FNSTSM and IFNSTSM controllers, the latter exhibits significant performance variations as the mean of variables changes. This research contributes to affordable and effective pediatric gait assistance, improving rehabilitation outcomes and enhancing mobility support.
... Importance of identifying the terrain 53 spoke the in which the human assistive devices are working on to conserve energy and to optimize the performance. 54,55 speaks the various areas in which exo-skeleton has a positive impact and says about the research trend in medical and non-medical applications and to bring the current developments and gives a clue to address the future issues. 12,56 made a review study on the transmission of exo skeleton in terms of controller design, actuation method, etc. Human gait cycle and walking pattern is mimicked 57 in the developed a humanoid robot to create a walking pattern for handling materials and in pushing wheeled carts in workplace environment. ...
... Set of rules and guidelines 54 were illustrated and encourages the usage of exo-skeletons and makes a note for the need of systematic development process during the design of exo-skeletons based on the VDI 2221 58 guidelines. EN ISO 13482 is another guideline for low-risk assistive robots. ...
Exo-Skeleton is a wearable robotic device which was emerged in later 1960s that has a multitude of applications ranging from weightlifting to wearer’s stability improvement. This paper makes a novel approach in reviewing the various exo-skeleton models that are available at the present. The idea of this paper is to study and compare the models in terms of medical applicability like gait rehabilitation, physiotherapy, human strength augmentation, various control strategies of exo-skeleton, ergonomic study, and need for exo-skeleton system for enhancing the life of humans. Since exo-skeletons are wearable devices, it requires precise controlling of the actuators and repeatability, and accuracy plays a vital role. The paper elucidated with a detailed analysis, reviewed and summarized the core essence of 300 research papers and patents in the field of exo-skeleton with the aforesaid aspects of application and drive system with their control methodologies from 2007 to 2022 and shown a trend with year-wise data from which it is clear that the future of industrial work will become a collaborative activity involving the exo-skeleton system with human labours. Human – robot interaction is vital and must for enabling an integration which can be achieved with the amelioration in the control and actuation techniques for precise control. With the furtherance in the technology the exo-skeletons can be purpose built that can be of rigid or flexible structures with active, passive, or quasi-passive controls based on the user needs. Joint handed operation of Exo-skeleton with the alternative treatment methodologies will yield a plethora of benefits in the near future in comparison with the present conventional treatment modes that could result in reduction of surgeries.
... ing human mobility [1][2][3][4]. These devices can be separated into three different categories: assistive exoskeletons, rehabilitation exoskeletons, and augmentation exoskeletons. ...
... ascending stairs, θ > 0 and θ f > 0 and θ h ≈ 0 descending stairs, θ < 0 and θ f < 0 and θ h ≈ 0 ascending ramps, θ > 0 and θ h ≈ θ descending ramps, θ < 0 and θ h ≈ θ, (1) where θ is the TS, θ f and θ h are the angles between the front or rear foot and the ground when the front foot touches the ground respectively. Based on this determination, the current movement can be classified into four walking tasks: ascending ramps, descending ramps, ascending stairs, and descending stairs. ...
Lower limb augmentation exoskeletons (LLAE) have been applied in several domains to enforce human walking capability. As humans can adjust their joint moments and generate different amounts of mechanical energy while walking on different terrains, the LLAEs should provide adaptive augmented torques to the wearer in multi-terrain environments, which requires LLAEs to implement accurate terrain parameter recognition. However, the outputs of previous terrain parameter recognition algorithms are more redundant, and the algorithms have higher computational complexity and are susceptible to external interference. Therefore, to resolve the above issues, this paper proposed a neural network regression (NNR)-based algorithm for terrain slope parameter recognition. In particular, this paper defined for the first time a unified representation of terrain parameters: terrain slope (TS), a single parameter that can provide enough information for exoskeleton control. In addition, our proposed NNR model uses only basic human parameters and LLAE joint motion posture measured by an Inertial Measurement Unit (IMU) as inputs to predict the TS, which is computationally simpler and less susceptible to interference. The model was evaluated using K-fold cross-validation and the results showed that the model had an average error of only 2.09 $$^\circ $$ ∘ . To further validate the effectiveness of the proposed algorithm, it was verified on a homemade LLAE and the experimental results showed that the proposed TS parameter recognition algorithm only produces an average error of 3.73 $$^\circ $$ ∘ in multi-terrain environments. The defined terrain parameters can meet the control requirements of LLAE in urban multi-terrain environments. The proposed TS parameter recognition algorithm could facilitate the optimization of the adaptive gait control of the exoskeleton system and improve user experience, energy efficiency, and overall comfort.
... Walking assistive devices have a distinct control strategy based on terrain types [4], [5], [6]. When such a device does not obtain information about a user's intention and/or upcoming gait environments in advance, it cannot accomplish the desired control strategy [7]. As a result, recognizing users' intentions and/or gait environments in advance is required to properly control walking assistive devices safely based on walking conditions. ...
Although studies on terrain identification algorithms to control walking assistive devices have been conducted using sensor fusion, studies on transition classification using only electromyography (EMG) signals have yet to be conducted. Therefore, this study was to suggest an identification algorithm for transitions between walking environments based on the entire EMG signals of selected lower extremity muscles using a deep learning approach. The muscle activations of the rectus femoris, vastus medialis and lateralis, semitendinosus, biceps femoris, tibialis anterior, soleus, medial and lateral gastrocnemius, flexor hallucis longus, and extensor digitorum longus of 27 subjects were measured while walking on flat ground, upstairs, downstairs, uphill, and downhill and transitioning between these walking surfaces. An artificial neural network (ANN) was used to construct the model, taking the entire EMG profile during the stance phase as input, to identify transitions between walking environments. The results show that transitioning between walking environments, including continuously walking on a current terrain, was successfully classified with high accuracy of 95.4 % when using all muscle activations. When using a combination of muscle activations of the knee extensor, ankle extensor, and metatarsophalangeal flexor group as classifying parameters, the classification accuracy was 90.9 %. In conclusion, transitioning between gait environments could be identified with high accuracy with the ANN model using only EMG signals measured during the stance phase.
... Today, as a result of the increasing demand for assistive technologies, interest in expanding portable rehabilitation systems has increased [1,2]. The knee joint arthrosis, referred to by various terms in the literature such as lower limb exoskeleton, shank arthrosis system, or knee rehabilitation robot, serves predominantly to facilitate the rehabilitation of individuals afflicted by impaired limb functionality at the knee joint level. ...
This study delves into the implementation of Fast Finite Time Fractional-Order Adaptive Sliding Mode Control (FFOASMC) for knee joint orthosis (KJO) in the presence of undisclosed dynamics. To achieve this, a novel approach introduces a Fractional-Order Sliding Surface (FOSS). In the context of limited knowledge regarding the dynamics of knee joint arthrosis, Fractional-Order Fast Adaptive Sliding Mode Control (FOFASMC) is devised. Its purpose is to ensure both finite-time stability and prompt convergence of the KJO’s state to the desired trajectory. This controller employs adaptive rules to estimate the enigmatic dynamic parameters of KJO. Through the application of the Lyapunov theorem, the attained finite-time stability of the closed loop is demonstrated. Simulation results effectively showcase the viability of these approaches and offer a comparative analysis against conventional integer-order sliding mode controllers.
... Moreover, the significant benefits of the manual therapy are lost if ever the process is withdrawn for even a short period [3]. Therefore, to address the limitations of conventional methods, the proliferation of exoskeleton technology has been observed for lower-limb rehabilitation [4][5][6][7][8]. ...
Over the last decade, lower limb exoskeletons have seen significant development, with a particular focus on improving the interaction between the subject and the exoskeleton. This has been achieved by implementing advanced control strategies that enable the safe and efficient use of the exoskeleton. In this work, the control strategies for lower limb exoskeletons are divided into upper-level control (supervisory and high-level control) and lower-level control (the servo layer). Before discussing these control strategies, a brief introduction to lower limb exoskeletons and their control schemes is provided. The control hierarchy for lower limb exoskeletons is then systematically reviewed along with an overview of the techniques used. A Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement is used to highlight the systematic process of identifying relevant articles with inclusion and exclusion criteria. The details of supervisory control, high-level control, and servo control strategies are presented by citing relevant state-of-the-art studies, particularly from the past five years. The targeted lower limb joint, training mode, and development stage for different control strategies are highlighted in a tabulated form to articulate the overall hierarchy level. Finally, the potential opportunities and limitations of subject-cooperative control are discussed. Overall, this work aims to provide an in-depth understanding of the control strategies used in lower limb exoskeletons, focusing on subject cooperation. This knowledge can be used to improve the safety and efficacy of lower limb exoskeletons, ultimately benefiting individuals with mobility impairments.
... LiPo technology is an excellent choice for wearable robots, as it fits most of the requirements for current variation, specific power and safety. LiPo battery packs have indeed been used in several exoskeletons, although newer exoskeletons increasingly rely on Lithium-ion chemistries [41,42]. Specifics about the battery chemistry of wearable robots are, however, rarely reported. ...
Untethered robots carry their own power supply in the form of a battery pack, which has a crucial impact on the robot’s performance. Although battery technologies are richly studied and optimized for applications such as electric vehicles, computers and smartphones, they are often a mere afterthought in the design process of a robot system. This tutorial paper proposes criteria to evaluate the suitability of different battery technologies for robotic applications. Taking into consideration the requirements of different applications, the capabilities of relevant battery technologies are evaluated and compared. The tutorial also discusses current limitations and new technological developments, pointing out opportunities for interdisciplinary research between the battery technology and robotics communities.
