Slower than normal walking speeds involve a pattern shift in joint and temporal coordination contributions

Complex pedestrian or passenger crowd movements, such as intersecting movements, can create a bottleneck resulting in delays during emergency escape from public infrastructure such as major public transport hubs. Limited studies have examined the effect of different intersecting angles and walking speeds on pedestrian outflow. This study aims to systematically investigate the effect of different intersecting angles (30°, 90°, and 150°) and walking speeds (normal walking, faster walking) on pedestrian outflow at an intersecting path or junction through controlled laboratory experiments. Further, we consider both blocked vision and un-blocked vision in our experiments. The results from our experiments show that the acute angle of 30° has a higher flow rate and less evacuation time as compared to the other angles. The obtuse intersecting angle of 150° was the most undesirable intersecting angle in terms of outflow, evacuation time, and delays at the junction. Faster walking generally led to reduced evacuation time as compared to normal walking. It is also interesting to note that the results from both blocked vision and un-blocked vision were not statistically significant, suggesting that line of sight was not an important factor in regulating the flow at the junction. The results from our findings are a valuable resource to verify the mathematical model intended to simulate pedestrian or passenger crowd movements and behavior within major public infrastructure under both normal and evacuation conditions.

Download Full-text

Mathematical modelling and field trials of an inexpensive endoskeletal above-knee prosthesis

Prosthetics and Orthotics International ◽

10.3109/03093649209164323 ◽

1992 ◽

Vol 16 (2) ◽

pp. 118-123 ◽

Cited By ~ 8

Author(s):

D. Mohan ◽

P. K. Sethi ◽

R. Ravi

Keyword(s):

Mathematical Modelling ◽

Knee Prosthesis ◽

Field Trials ◽

Swing Phase ◽

Normal Walking ◽

Flat Surfaces ◽

Hinge Joint ◽

Normal Gait ◽

Walking Speeds ◽

Phase Motion

The swing-phase motion of the shank of an above-knee prosthesis has been modelled mathematically. An inexpensive endoskeletal prosthesis was designed using the Jaipur foot and conduit pipes with a hinge joint for the knee. Results of field trials and the modelling indicate that a very simple above-knee prosthesis can give near normal gait at “normal” walking speeds on flat surfaces. The swing of the shank is most sensitive to the timing of toe-off.

Download Full-text

Identification of Disability Risk in Addition to Slow Walking Speed in Older Adults

Gerontology ◽

10.1159/000516966 ◽

2021 ◽

pp. 1-10

Author(s):

Hiroyuki Shimada ◽

Takehiko Doi ◽

Sangyoon Lee ◽

Kota Tsutsumimoto ◽

Seongryu Bae ◽

...

Keyword(s):

Older Adults ◽

Regression Models ◽

Walking Speed ◽

Word List ◽

Normal Walking ◽

Slow Walking ◽

List Memory ◽

Walking Speeds ◽

Walking Group ◽

Slow Walking Speed

Introduction: A cutoff speed of 1.0 m/s for walking at a comfortable pace is critical for predicting future functional decline. However, some older adults with walking speeds below the cutoff point maintain an independent living. We aimed to identify specific predictors of disability development in older adults with slow walking speeds in contrast to those with a normal walking speed. Methods: This prospective cohort study on 12,046 community-dwelling independent Japanese older adults (mean age, 73.6 ± 5.4 years) was conducted between 2011 and 2015. Participants were classified into slow walking speed (comfortable walking speed slower than 1.0 m/s) and normal walking speed (speed of 1.0 m/s or faster) groups and followed up to assess disability incidence for 24 months after baseline assessments. Cox proportional hazards regression models were used to identify predictors of disability development in the slow and normal walking groups. Results: Overall, 26.8% of participants had a slow walking speed. At follow-up, 17.3% and 5.1% of participants in the slow and normal walking groups, respectively, developed disability (p < 0.01). Cox regression models revealed that age (hazard ratio 1.07, 95% confidence interval 1.05–1.09), walking speed (0.12, 0.07–0.22), grip strength (0.97, 0.95–0.99), Parkinson’s disease (4.65, 2.59–8.33), word list memory-immediate recognition score (0.90, 0.85–0.97), word list memory-delayed recall score (0.94, 0.89–1.00), Symbol Digit Substitution Test (SDST) score (0.98, 0.96–0.99), and 15-item Geriatric Depression Scale (GDS) score (1.04, 1.01–1.07) were significantly associated with disability incidence in the slow walking group. In the normal walking group, age, grip strength, depression, diabetes, cognition, GDS score, and reduced participation in outdoor activity were significantly associated with disability incidence; however, there was no significant association with walking speed. Conclusions: Decreased walking speeds have considerably greater impact on disability development in older adults with a slow walking speed than in those with a normal walking speed. Health-care providers should explore modifiable factors for reducing walking speed; they should also encourage improvement of risk factors such as muscle weakness and depression to reduce disability risk in older adults with slow walking speeds.

Download Full-text

Inter-joint and temporal coordination change in very slow walking

10.1101/588095 ◽

2019 ◽

Author(s):

Virginia L. Little ◽

Theresa E. McGuirk ◽

Carolynn Patten

Keyword(s):

Motor Behavior ◽

Temporal Coordination ◽

Joint Coordination ◽

3D Motion Analysis ◽

Slow Walking ◽

Joint Influence ◽

Gait Parameters ◽

Additional Support ◽

Coordination Change ◽

Walking Speeds

AbstractPurposeVery slow walking has been suggested to be a distinctively different motor behavior than walking at comfortable gait speeds. While kinematic and spatiotemporal gait parameters are known to scale with gait speed, inter-joint coordination during swing remains consistent, at least across comfortable speeds. The purpose of this study was to determine whether coordination patterns serving limb clearance and shortening differ with very slow walking, providing additional support for the premise that very slow walking represents a unique motor behavior.MethodsWe assessed nine healthy adults walking overground at their self-selected speed and two-to-three progressively slower speeds. We collected lower extremity kinematics with 3D motion analysis and quantified joint motion contributions to limb clearance and shortening. We investigated changes in coordination using linear mixed models to determine magnitude and timing differences of joint influence across walking speeds.ResultsHip and knee influences serving limb clearance reduced considerably with slower walking speeds. Similarly, knee influence on limb shortening reduced with very slow walking. Importantly, ankle influence remained unchanged across gait speeds for limb shortening and reduced subtly for limb clearance. Temporally, joint influences on limb clearance varied across walking speeds. Specifically, the temporal order of peak hip and knee influences reversed between comfortable and very slow walking. For limb shortening the timing of ankle influence remained unchanged while the timing of knee influence occurred later in the gait cycle for slower walking speeds.ConclusionsOur results demonstrate temporal coordination and the relative joint contributions serving limb clearance and shortening differ with very slow walking providing additional evidence that slow walking may be a behavior distinct from walking at comfortable speeds.

Download Full-text

A Passive Ankle-Foot Prosthesis With Energy Return to Mimic Able-Bodied Gait

Volume 5A: 41st Mechanisms and Robotics Conference ◽

10.1115/detc2017-67192 ◽

2017 ◽

Author(s):

Robert Holgate ◽

Thomas Sugar ◽

Audrey Nash ◽

Jasper Kianpour ◽

Craig Trevor Johnson ◽

...

Keyword(s):

Ankle Joint ◽

Swing Phase ◽

Heel Strike ◽

Normal Walking ◽

Passive Mechanism ◽

Ground Slope ◽

Breaking Energy ◽

Walking Speeds

It has been shown previously that for slow to normal walking speeds the ankle joint behaves similar to a passive mechanism from foot flat to push off. Thus a passive ankle mechanism was developed in order to mimic able-bodied gait in amputees. The ankle device is shown to be capable of matching the ground slope during heel strike, efficiently storing breaking energy from the user during rollover then releasing that energy to assist in push off, and raising the toe during swing phase to reset the system for the next heel strike. Mechanism functionality was verified through lab testing. Human testing was done through an ankle-bypass system on able-bodied subjects to verify device safety and functionality.

Download Full-text