Many disease-specific factors such as muscular weakness, increased muscle stiffness, varying postural strategies, and changes in reflexes have been shown to lead instability fall risk people with Parkinson's disease (PD). Recently, analytical techniques, inspired by the dynamical systems perspective on movement control coordination, used examine mechanisms underlying dynamics of declines emergence instabilities PD. A wavelet-based technique was identify limit cycle oscillations (LCOs)...

Abstract Study of human upright posture (UP) stability is great relevance to fall prevention and rehabilitation, especially for those with balance deficits whom a board (BB) widely used mechanism improve balance. The the human-BB system has been investigated from dynamical point view. However, most studies assume small disturbances, which allow linearize nonlinear system, neglecting effect terms on stability. Such assumption useful simplify use bifurcation analyses determine local dynamic...

Mathematical models of human posture on a rigid surface predict two types balance instabilities — static tipping instability and dynamic leading to large oscillations. Although common technique improve performance is placing patients boards, little research has modeled bipedal rotational boards better understand the mechanisms underlying improvement. In this study we present mathematical model stance single-degree-of-freedom board with controllable torsional stiffness delayed feedback....

Neurological disorders, a concussion, or aging can extend the time-delay in human neuromuscular balance system; this increase has been shown [5] to be an important factor contributing loss of balance. However, commercial boards used help improve individual’s deficiencies do not utilize as tunable parameter. In order systematically study stiffness and induced instabilities standing posture, we developed active board system with controllable torsional stiffness, well added feedback board....

Abstract Trust is crucial for integrating autonomous vehicles (AVs) into society, with various studies examining pedestrian trust through methods like images, texts, videos, virtual reality (VR), and field studies. The impact of these representational on assessment remains uncertain. Our study conducted a 2 (media types: VR vs. video) by 7 (vehicle behavior trials) within-subject experiment 50 adults to compare trust, risk perception, comprehensibility in immersive non-immersive video...

Portable force-measurement technologies are becoming increasingly popular tools to examine the maturation of postural motor milestones, such as sitting and standing, in infants. These convenient, low-cost devices provide numerous opportunities characterize development outside laboratory. However, it is important understand unique challenges technical limitations associated with collecting center pressure (CoP) data using portable infant populations. This study uses a mathematical model...

Recent mathematical models of human posture have been explored to better understand the space control parameters that result in stable upright balance. These demonstrated there are two types instabilities — a leaning instability and an leading excessive oscillation. While these provide insight into stability bipedal stance, they not sufficient for individuals require aid assistive technologies, such as passive-cane or walker. Without valid model one is unable required maintain if similar...

A balance board is an unstable platform which currently used for training and rehabilitation to stabilize individual’s upright posture. Models that examine how individuals remain while standing on surface are therefore needed understand the mechanisms behind improvements. Most research in this area has focused fluctuations posture about a static equilibrium using single-degree-of-freedom (1-DOF) inverted pendulum models [1–2]. While conceptually simple, these nonetheless capture stochastic,...

Abstract During individual training on a balance board (BB), misalignment between the ankle joint and BB axis of rotation may exist. The ankle-pivot influences dynamics human more importantly, stability properties equilibrium positions human-BB dynamical system. Similarly, displacement in upward direction with respect to pivot also plays critical role This paper investigates these effects through bifurcation analyses performed ankle-hip model developed our previous work. By using local...

Mathematical models predict limit cycle oscillations (LCOs) in postural sway when the combination of neuromuscular time-delay and feedback gains are excessively large. LCOs have been observed standing posture various populations known to longer time-delays including concussed young adults with impairment such as multiple sclerosis (MS) Parkinsons disease (PD) but not healthy controls. However, relationship between gain that leads these has yet be explored experimentally. In this study, we...

Abstract The study of human postural instability and its mechanism is critical for understanding the fall mechanics underlying factors engendering in balance. This especially crucial given that identification these instabilities aid risk, prevention strategies, rehabilitation post-fall. In this study, we analyze upright stance mechanisms responsible induction through artificial manipulation visual sensory feedback time application virtual reality (VR). Previous studies have established...

Abstract Understanding the mechanisms behind human balance has been a subject of interest as various postural instabilities have linked to neuromuscular diseases (Parkinson’s, multiple sclerosis, and concussion). This paper presents classification method for an individual’s stability estimation their feedback control parameters. The uses generated topological mapping between subjects experimental data set consisting time series realizations using inverted pendulum mathematical model upright...

Abstract Understanding the mechanisms behind human balance has been a subject of interest as various postural instabilities have linked to neuromuscular diseases (e.g., Parkinson's, multiple sclerosis, and concussion). This paper presents method characterize an individual's stability estimate their feedback control parameters. The uses generated topological mapping between subject's experimental data dataset consisting time-series realizations using inverted pendulum mathematical model...

Abstract Autonomous shuttles are becoming a widely used form of public transportation. While autonomous have advantages to improve safety, potential riders expressed concerns about falls and injuries sustained during braking events. In the current study we investigated effects multiple warning design parameters, including modality temporal aspects stimulus, on balance maintenance simulated hard event. Two stimuli were — an auditory stimulus visual stimulus. We effect timing in attempt...