Preliminary investigation of effects of a quasi-passive knee exoskeleton on gait energetics

Shamaei, Kamran; Adams, Albert A.; Cenciarini, Massimo; Gregorczyk, Karen N.; Dollar, Aaron M.

doi:10.1109/embc.2014.6944269

Cited by 7 publications

(6 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The kinematic constraints imposed by the exoskeleton joint resulted in a slightly more flexed knee at the heel strike, which could be a result of limited range of motion of the exoskeleton joints (as fabrication imperfection), as it was reported by the participants about the left exoskeleton. In another study, we found that the exoskeleton mass is the main contributor to the increase in the metabolic cost of walking [59]. Here we found that the exoskeleton mass caused an upscale in the range of joint moments suggesting that minimization of the exoskeleton mass should be a main goal in the design of exoskeletons.…”

Section: Discussionmentioning

confidence: 51%

See 1 more Smart Citation

Biomechanical Effects of Stiffness in Parallel With the Knee Joint During Walking

Shamaei

Cenciarini²,

Adams

et al. 2015

IEEE Trans. Biomed. Eng.

Self Cite

View full text Add to dashboard Cite

The human knee behaves similarly to a linear torsional spring during the stance phase of walking with a stiffness referred to as the knee quasi-stiffness. The spring-like behavior of the knee joint led us to hypothesize that we might partially replace the knee joint contribution during stance by utilizing an external spring acting in parallel with the knee joint. We investigated the validity of this hypothesis using a pair of experimental robotic knee exoskeletons that provided an external stiffness in parallel with the knee joints in the stance phase. We conducted a series of experiments involving walking with the exoskeletons with four levels of stiffness, including 0%, 33%, 66%, and 100% of the estimated human knee quasi-stiffness, and a pair of joint-less replicas. The results indicated that the ankle and hip joints tend to retain relatively invariant moment and angle patterns under the effects of the exoskeleton mass, articulation, and stiffness. The results also showed that the knee joint responds in a way such that the moment and quasi-stiffness of the knee complex (knee joint and exoskeleton) remains mostly invariant. A careful analysis of the knee moment profile indicated that the knee moment could fully adapt to the assistive moment; whereas, the knee quasi-stiffness fully adapts to values of the assistive stiffness only up to ∼80%. Above this value, we found biarticular consequences emerge at the hip joint.

show abstract

Section: Discussionmentioning

confidence: 51%

“…ankle and hip) under the effect of assistance to the knee joint to examine the locality of the external stiffness effects. Lastly, we intend to investigate the effect of the exoskeleton on the metabolic cost of locomotion [59].…”

Section: Discussionmentioning

confidence: 99%

Biomechanical Effects of Stiffness in Parallel With the Knee Joint During Walking

Shamaei

Cenciarini²,

Adams

et al. 2015

IEEE Trans. Biomed. Eng.

Self Cite

View full text Add to dashboard Cite

show abstract

“…#W911NF-07-D-0001). Yale University Kamran Shamaei et al [131] studied the auxiliary effect provided by a quasi-passive knee exoskeleton (Figure 8f). The knee exoskeleton is composed of motors, worm gear sets, and springs assembled on the thigh segment of the exoskeleton.…”

Section: Knee-assisted Exoskeletonmentioning

confidence: 99%

A Wearable Lower Limb Exoskeleton: Reducing the Energy Cost of Human Movement

Tang

Zhou

et al. 2022

Micromachines

View full text Add to dashboard Cite

Human body enhancement is an interesting branch of robotics. It focuses on wearable robots in order to improve the performance of human body, reduce energy consumption and delay fatigue, as well as increase body speed. Robot-assisted equipment, such as wearable exoskeletons, are wearable robot systems that integrate human intelligence and robot power. After careful design and adaptation, the human body has energy-saving sports, but it is an arduous task for the exoskeleton to achieve considerable reduction in metabolic rate. Therefore, it is necessary to understand the biomechanics of human sports, the body, and its weaknesses. In this study, a lower limb exoskeleton was classified according to the power source, and the working principle, design idea, wearing mode, material and performance of different types of lower limb exoskeletons were compared and analyzed. The study shows that the unpowered exoskeleton robot has inherent advantages in endurance, mass, volume, and cost, which is a new development direction of robot exoskeletons. This paper not only summarizes the existing research but also points out its shortcomings through the comparative analysis of different lower limb wearable exoskeletons. Furthermore, improvement measures suitable for practical application have been provided.

show abstract

“…This paper presents a brace concept that aims to reduce the first peak total KCF during gait through muscle compensation by applying an external knee extension moment. The concept of applying a knee flexion/extension moment to assist human muscles is common within exoskeletons, which either apply the moment actively [27][28][29][30] or quasi-passively [31][32][33][34]. The latter refers to an active control, but the moment is applied passively from, e.g., springs and, hence, there is no mechanical energy added to the system.…”

Section: Introductionmentioning

confidence: 99%

“…The main goal of exoskeletons is to provide assistance and compensate for the joint moments to reduce muscle activation, but the purpose can vary. When dealing with the lower extremity, metabolic cost is most often the main evaluation factor [31,35,36,40], which improves endurance for various activities and load-carrying tasks. However, as previously mentioned, the muscle compensation in the sagittal plane may also lead to a reduced KCF and thereby potentially slow down KOA progression.…”

Section: Introductionmentioning

confidence: 99%

Investigation of bracing to unload muscle and knee contact forces for knee oteoarthritis patients: Modelling, workflow, prototype design and evaluation

Stoltze¹

View full text Add to dashboard Cite

General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.-Users may download and print one copy of any publication from the public portal for the purpose of private study or research. -You may not further distribute the material or use it for any profit-making activity or commercial gain -You may freely distribute the URL identifying the publication in the public portal -

show abstract

Preliminary investigation of effects of a quasi-passive knee exoskeleton on gait energetics

Cited by 7 publications

References 24 publications

Biomechanical Effects of Stiffness in Parallel With the Knee Joint During Walking

Biomechanical Effects of Stiffness in Parallel With the Knee Joint During Walking

A Wearable Lower Limb Exoskeleton: Reducing the Energy Cost of Human Movement

Investigation of bracing to unload muscle and knee contact forces for knee oteoarthritis patients: Modelling, workflow, prototype design and evaluation

Contact Info

Product

Resources

About