Wheeled Walker Research Articles

Research on Walking Wheel Slippage Control of Live Inspection Robot

To solve the problem of walking wheel slippage of a live inspection robot during walking or climbing, this paper analyzes the climbing capacity of the robot with a statics method, designs a pressing wheel mechanism, and presents a method of indirectly identifying walking wheel slippage by reading speed of the pressing wheel due to the fact that the linear speed of the pressing wheel and the walking wheel at the contract point is the same; and finds that the slippage state can not be controlled through accurate mathematical models after identifying the slippage state, whereas slippage can be controlled with fuzzy control. The experiment results indicate that due to design of the pressing wheel mechanism, friction force of the walking wheel is increased, and the climbing capability of the robot is improved. Within the range of climbing capability of the robot, gradient is the key factor that has influence on slippage of robot, and slippage can be effectively eliminated through the fuzzy control method proposed in this paper.

Instrumented gait analysis: a measure of gait improvement by a wheeled walker in hospitalized geriatric patients

BackgroundIn an increasing aging society, reduced mobility is one of the most important factors limiting activities of daily living and overall quality of life. The ability to walk independently contributes to the mobility, but is increasingly restricted by numerous diseases that impair gait and balance. The aim of this cross-sectional observation study was to examine whether spatio-temporal gait parameters derived from mobile instrumented gait analysis can be used to measure the gait stabilizing effects of a wheeled walker (WW) and whether these gait parameters may serve as surrogate marker in hospitalized patients with multifactorial gait and balance impairment.MethodsOne hundred six patients (ages 68–95) wearing inertial sensor equipped shoes passed an instrumented walkway with and without gait support from a WW. The walkway assessed the risk of falling associated gait parameters velocity, swing time, stride length, stride time- and double support time variability. Inertial sensor-equipped shoes measured heel strike and toe off angles, and foot clearance.ResultsThe use of a WW improved the risk of spatio-temporal parameters velocity, swing time, stride length and the sagittal plane associated parameters heel strike and toe off angles in all patients. First-time users (FTUs) showed similar gait parameter improvement patterns as frequent WW users (FUs). However, FUs with higher levels of gait impairment improved more in velocity, stride length and toe off angle compared to the FTUs.ConclusionThe impact of a WW can be quantified objectively by instrumented gait assessment. Thus, objective gait parameters may serve as surrogate markers for the use of walking aids in patients with gait and balance impairments.

Effect of uphill and downhill walking on walking performance in geriatric patients using awheeled walker.

Wheeled walkers are recommended to improve walking performance in older persons and to encourage and assist participation in daily life. Nevertheless, using awheeled walker can cause serious problems in the natural environment. This study aimed to compare uphill and downhill walking with walking level in geriatric patients using awheeled walker. Furthermore, we investigated the effect of using awheeled walker with respect to dual tasking when walking level. A total of 20 geriatric patients (median age 84.5years) walked 10m at their habitual pace along alevel surface, uphill and downhill, with and without astandard wheeled walker. Gait speed, stride length and cadence were assessed by wearable sensors and the walk ratio was calculated. When using awheeled walker while walking level the walk ratio improved (0.58 m/[steps/min] versus 0.57 m/[steps/min], p= 0.023) but gait speed decreased (1.07 m/s versus 1.12 m/s, p= 0.020) when compared to not using awheeled walker. With respect to the walk ratio, uphill and downhill walking with awheeled walker decreased walking performance when compared to level walking (0.54 m/[steps/min] versus 0.58 m/[steps/min], p= 0.023 and 0.55 m/[steps/min] versus 0.58 m/[steps/min], p= 0.001, respectively). At the same time, gait speed decreased (0.079 m/s versus 1.07 m/s, p< 0.0001) or was unaffected. The use of awheeled walker improved the quality of level walking but the performance of uphill and downhill walking was worse compared to walking level when using awheeled walker.

Value-based design for the elderly: An application in the field of mobility aids

ABSTRACTIn the aging society, the need for the elderly to remain mobile and independent is higher than ever. However, many aids supporting mobility often fail to target real needs and lack acceptance. The aim of this study is to demonstrate how value-based design can contribute to the design of mobility aids that address real needs and thus, lead to high acceptance. We elicited values, facilitators, and barriers of mobility of older adults via ten in-depth interviews. Next, we held co-creation sessions, resulting in several designs of innovative mobility aids, which were evaluated for acceptance via nine in-depth interviews. The interviews resulted in a myriad of key values, such as “independence from family” and “doing their own groceries.” Design sessions resulted in three designs for a wheeled walker. Their acceptance was rather low. Current mobility device users were more eager to accept the designs than non-users. The value-based approach offers designers a close look into the lives of the elderly, thereby opening up a wide range of innovation possibilities that better fit their actual needs. Product service systems seem to be a promising focus for targeting human needs in mobility device design.

Improved Walking Capabilities after Eight Weeks of Hal® Exoskeleton-Supported Treadmill Therapy in a Patient with Limb-Girdle Muscular Dystrophy Type 2I

A 57-year-old woman suffering from limb-girdle muscular dystrophy type 2I (LGMD, fukutin-related protein gene mutation) took part in body-weight supported treadmill therapy with the voluntary driven exoskeleton HAL®. First clinical signs were evident 11 years ago. The diagnosis has been determined genetically in 2009. Clinical examination showed floppy quadriparesis with typical proximal pronouncement (MRC 3-4/5), positive Trendelenburg sign bilateral and lumbar hyperlordosis. Due to the muscular dystrophy, the patient is retired. She needs a wheeled walker to deal with longer distances, e. g shopping. Her muscle weakness causes falls regularly. The patient gave written informed consent to participate in a clinical application observation.

Comparative Study of Mobility and Perceived Exertion for the Wheeled Knee Walker and Axillary Crutches in Healthy Participants

Category: Other Introduction/Purpose: Functional limitations are common after lower extremity surgery and often require the use of an assistive device for ambulation during rehabilitation and recovery. There is no known data evaluating the wheeled knee walker (WKW) as an assistive device for postoperative protected ambulation. The purpose of this study is to compare mobility and perceived exertion in the WKW and the axillary crutch (AC) in healthy volunteers. Methods: This is a cross sectional study of the WKW and the AC that was performed on 24 healthy volunteers utilizing the Six- Minute Walk Test (6MWT). The participants were randomized into two separate arms, one starting with the AC (N=12) and one starting with the WKW (N=12). A modified version of the American Thoracic Society (ATS) Guidelines for the 6MWT was performed for both assistive devices on all subjects. Pre-activity and post-activity heart rates were recorded for both events. From the 6MWT data the values for the Self Selected Walking Velocity (SSWV) were calculated and the subjects rating of perceived exertion was recorded using the OMNI Rating of Perceived Exertion (OMNI-RPE). Patient's preference for assistive device was identified. Results: The 6MWT, SSWV and the Omni-RPE were evaluated using paired T-tests and was determined to be statistically significant for the WKW when compared to the AC (p &lt; 0.001). The confounding effect of the sequences were measured utilizing a mixed-model 2x2 ANOVA and was determined to have no significant 3 way (time x device x sequence) interaction (p = 0.968). Factorial 2 x 2 repeated measures ANOVA was used to evaluate the pre-activity and post-activity heart rates and demonstrated a statistically significant difference for the WKW when compared to the AC (p &lt; 0.001). 87.5% of subjects preferred the WKW to the AC. Conclusion: The WKW provided increased mobility and had a lower rating of perceived exertion than the AC on level surfaces in healthy participants

Mobile robotic cart development to support home oxygen therapy patients: Study on handling interface for mobile robotic cart similar to wheeled walker

We propose a motion control interface system for a mobile robotic cart to support Home Oxygen Therapy (HOT) patients when they go out. Our goal is to realize a mobile robotic cart similar to a wheeled walker that carries oxygen devices in front of patients, because HOT patients whose physical strength has especially waned would like to use such a cart according to the results of our questionnaire given to patients. The proposed handling interface of the mobile robotic cart adopts simple mechanisms and commonly used force sensors to sense only pushing and pulling forces from the user. We also apply a two-degrees-of-freedom (2 D.O.F.) control system to control the velocity and response time of the robotic cart. The feedforward controller of the 2 D.O.F. control system, which is an impedance-adjustable element, is expected to be used not only to adjust the response time but also to compensate for interference between the forces applied by the user and the robotic cart during operation. In this study we evaluated the effectiveness of our proposed handling interface mechanisms and control system by performing several experiments on a prototype robotic cart, and then we carried out user tests on some HOT patients and received a positive evaluation of the robotic cart’s performance.

IMU Sensor based Human Motion Detection and Its Application to Braking Control of Electric Wheeled Walker for Fall-prevention

IMU Sensor based Human Motion Detection and Its Application to Braking Control of Electric Wheeled Walker for Fall-prevention

片麻痺障がい者のための車輪型歩行アシスト機

This paper proposes a wheeled walking assistive apparatus that assists a person with hemiparesis. This apparatus has high stability comparing with leg types because its wheels always contact on the ground. In addition the user does not need to support the weight of it. The user wears the apparatus bending his/her hemiplegic knee. Differential gears provided between front wheels enable the user to rotate in the horizontal direction. The gas spring attached on rear wheels enables the user to tilt the apparatus forward easily. It is controlled based on the tilt angle calculated from the length measured with the linear sensor. Results obtained from experiments demonstrate that non-disabled persons can travel indoors stably.

Indoor Positioning of a Robotic Walking Assistant for Large Public Environments

Indoor localization and position tracking are essential to support applications and services for ambient-assisted living. While the problem of indoor localization is still open and already quite complex per se, in large public places, additional issues of cost, accuracy, and scalability arise. In this paper, the position estimation and tracking technique developed within the project devices for assisted living (DALi) is described, analyzed through simulations, and finally validated by means of a variety of experiments on the field. The goal of the DALi project is to design a robotic wheeled walker guiding people with psychomotor problems. Indeed, people with motor or cognitive impairments are often afraid of moving in large and crowded environments (e.g., because they could lose the sense of direction). In order to mitigate this problem, the position tracking approach described in this paper is based on multisensor data fusion and it is conceived to assure a good tradeoff between target accuracy, level of confidence, and deployment costs. Quite interestingly, the same approach could be used for indoor automated guided vehicles and robotics.

Problems of older persons using a wheeled walker.

Wheeled walkers (WWs) are used to improve mobility and for fall prevention in older persons, but not all users are satisfied with the usability of WWs. Intelligent WWs are being developed to improve the usability. The aim of this study was to support the development of intelligent WWs by investigating possible problems of using a WW. This study investigated 22 geriatric in-patients (median age 82years) with and without their WW while opening a door against the direction of walking and passing through. Other possible problems when using WWs were identified by interview. Walking through the door was faster without than with using the WW (8.71 versus 12.86s, p<0.001), while interference between door and WW was documented in 41 of 44 (93%) cases. Backward walking performance was better when using a WW with regard to gait speed, step width and walk ratio (all p<0.002). Most referred problems when using a WW were walking downhill (83%) and uphill (77%) and obstacle crossing in general (77%). Problems with opening a door against the direction of walking and the optimization of downhill and uphill walking as well as obstacle crossing should be regarded when developing an intelligent WW.

Neurotoxic overdose in a young man: answer

The man’s initial serum methanol level was found to be 231 mmol/L. The methanol level quickly responded to treatment, and was undetectable after 36 hours. One week after extubation, he was severely rigid and bradykinetic with significant weakness in his upper and lower extremities. He had also suffered severe visual impairment from retinal toxicity. Two months later, with the benefit of aggressive physiotherapy, he was ambulating with minimal assistance and a two wheeled walker, and had 4/5 gross motor strength in both his upper and lower extremities. Methanol poisoning is relatively uncommon, but carries a high mortality rate [1]. Ingested methanol is metabolized into formaldehyde and then formic acid by alcohol and formaldehyde dehydrogenases, respectively. The hallmarks of methanol poisoning are an anion gap metabolic acidosis and visual impairment. Formate causes demyelination and necrosis to the optic nerve and may cause permanent damage in 11–18% of patients [1,2]. Although rare, putamen necrosis has been previously documented in methanol toxicity [3–6]. Affected patients may exhibit rigidity,

Walking with a four wheeled walker (rollator) significantly reduces EMG lower-limb muscle activity in healthy subjects

To investigate the immediate effect of four-wheeled- walker(rollator)walking on lower-limb muscle activity and trunk-sway in healthy subjects. In this cross-sectional design electromyographic (EMG) data was collected in six lower-limb muscle groups and trunk-sway was measured as peak-to-peak angular displacement of the centre-of-mass (level L2/3) in the sagittal and frontal-planes using the SwayStar balance system. 19 subjects walked at self-selected speed firstly without a rollator then in randomised order 1. with rollator 2. with rollator with increased weight-bearing. Rollator-walking caused statistically significant reductions in EMG activity in lower-limb muscle groups and effect-sizes were medium to large. Increased weight-bearing increased the effect. Trunk-sway in the sagittal and frontal-planes showed no statistically significant difference between conditions. Rollator-walking reduces lower-limb muscle activity but trunk-sway remains unchanged as stability is likely gained through forces generated by the upper-limbs. Short-term stability is gained but the long-term effect is unclear and requires investigation.

How to carry out a field walking test in chronic respiratory disease.

Educational AimsTo provide recommendations for conducting field walking tests in people with chronic respiratory disease, from the new European Respiratory Society/American Thoracic Society Technical StandardTo provide information to assist in selecting a field walking test in people with chronic respiratory disease.Key pointsThe 6MWT, ISWT and ESWT are valid and reliable tests of functional exercise capacity in people with COPD. The 6MWT is also widely used in other chronic respiratory disorders.There is a learning effect for the 6MWT and ISWT, so two tests must be performed if the tests are being used to measure change over time, with the best distance recorded.The 6MWT is very sensitive to changes in the way it is conducted, including use of encouragement, provision of supplemental oxygen, changes in track layout and length, and use of wheeled walkers. These factors should be held constant when the test is repeated.The 6MWT, ISWT and ESWT are strenuous tests, with cardiorespiratory responses that are similar to those during a maximal incremental exercise test. As a result, the contraindications and precautions for these field walking tests should be the same as for a laboratory-based incremental exercise test.SummaryThe European Respiratory Society (ERS) and American Thoracic Society (ATS) have recently published a Technical Standard which documents the standard operating procedures for the 6-min walk test (6MWT), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT). The Technical Standard shows that all three tests are valid and reliable measures of functional exercise capacity in people with chronic respiratory disease and makes recommendations for standardising their performance. Key findings and recommendations of the Technical Standard include: The 6MWT, ISWT and ESWT are strenuous tests which elicit cardiorespiratory responses that are similar to those observed during a maximal incremental exercise test. As a result, the contraindications and precautions for field walking tests should be consistent with those used for a laboratory-based incremental exercise test.There is strong evidence of a learning effect for the 6MWT and ISWT. Two tests should be performed when the 6MWT or ISWT are used to measure change over time.The 6MWT, ISWT and ESWT are responsive to treatment effects in people with chronic respiratory disease, particularly for rehabilitation.The 6MWT is very sensitive to variations in methodology, including use of encouragement, provision of supplemental oxygen, changes in track layout and length, and use of wheeled walkers. These factors should be documented and held constant on repeat testing.The lowest SpO2 recorded during a 6MWT is an important marker of disease severity and prognosis. Continuous pulse oximetry is recommended during the 6MWT, to ensure that the lowest SpO2 is recorded.In adults with chronic respiratory disease, a change in 6-min walk distance of 30 m or more indicates a clinically significant change has occurred.

Sleep deprivation does not affect neuronal susceptibility to mild traumatic brain injury in the rat.

Mild and moderate traumatic brain injuries (TBIs) (and concussion) occur frequently as a result of falls, automobile accidents, and sporting activities, and are a major cause of acute and chronic disability. Fatigue and excessive sleepiness are associated with increased risk of accidents, but it is unknown whether prior sleep debt also affects the pathophysiological outcome of concussive injury. Using the “dark neuron” (DN) as a marker of reversible neuronal damage, we tested the hypothesis that acute (48 hours) total sleep deprivation (TSD) and chronic sleep restriction (CSR; 10 days, 6-hour sleep/day) affect DN formation following mild TBI in the rat. TSD and CSR were administered using a walking wheel apparatus. Mild TBI was administered under anesthesia using a weight-drop impact model, and the acute neuronal response was observed without recovery. DNs were detected using standard bright-field microscopy with toluidine blue stain following appropriate tissue fixation. DN density was low under home cage and sleep deprivation control conditions (respective median DN densities, 0.14% and 0.22% of neurons), and this was unaffected by TSD alone (0.1%). Mild TBI caused significantly higher DN densities (0.76%), and this was unchanged by preexisting acute or chronic sleep debt (TSD, 0.23%; CSR, 0.7%). Thus, although sleep debt may be predicted to increase the incidence of concussive injury, the present data suggest that sleep debt does not exacerbate the resulting neuronal damage.

The Lancet Respiratory Medicine's call for Essays

Science and literature often go hand-in-hand, and can cut, either literally or metaphorically, to the core of an issue, changing peoples' minds and perspective. We are therefore running once again an Essay competition and putting out a call to all budding authors working, studying, and researching on the frontline. Do you have a burning issue or clinical experience on which you wish to comment? Essays should be pieces of prose on any topic related to respiratory medicine or critical care and intensive medicine, and should be no more than 1500 words. Please see previously published Essays for examples of winning submissions. The deadline for submission is Oct 15, 2015. Entries will be judged anonymously by our editors, and the winner will receive a £400 prize and be published in print and online in December 2015. Fires and strikes: the politics of powerThe sun bursts through my window as it does every morning, lighting up the room and sidelining my alarm clock. But it feels different this morning. It is still bright and hot and humid. It smells the same…of course, it is quiet. It's never quiet. Where is the customary racket of motorbikes and music and barking and bellowing? I have come to accept, and even expect change, but this worries me. I scramble out of my mosquito net and look through the window. A stray cow munches on some rubbish but otherwise there is no sign of activity. Full-Text PDF Black nightMy first shift in the intensive care unit was forgettable. Full-Text PDF Patient, Doctor, Father, SonMrs Thompson made her way across the oncology waiting room slowly, carefully pushing the wheeled walker adorned with assorted stickers and laden with two cloth shopping bags. Our nurse Barbara was preparing to check her into the examination room, a process that promised to be laborious. You have time, she knowingly informed me, realising that Mrs Thompson was the last patient of the morning and that I would like to eat my sandwich before starting a visit which could take most of the lunch hour. Barbara was correct. Full-Text PDF

A wheeled walker improves physical activity in chronic obstructive pulmonary disease

L.W.C. Ng1,2,3, S. Jenkins 1,2,4, N. Cecins 2,4, P. Eastwood1,5,6, K. Hill 1,5 1 Curtin University of Technology, Physiotherapy and Exercise Science, Perth, Australia; 2 Sir Charles Gairdner Hospital, Physiotherapy, Perth, Australia; 3 Singapore General Hospital, Physiotherapy, Singapore, Singapore; 4 Lung Institute of Western Australia, Perth, Australia; 5 Sir Charles Gairdner Hospital, Pulmonary Physiology, Perth, Australia; 6 University of Western Australia, School of Anatomy and Human Biology, Perth, Australia

Inertial sensor-based stride parameter calculation from gait sequences in geriatric patients.

A detailed and quantitative gait analysis can provide evidence of various gait impairments in elderly people. To provide an objective decision-making basis for gait analysis, simple applicable tests analyzing a high number of strides are required. A mobile gait analysis system, which is mounted on shoes, can fulfill these requirements. This paper presents a method for computing clinically relevant temporal and spatial gait parameters. Therefore, an accelerometer and a gyroscope were positioned laterally below each ankle joint. Temporal gait events were detected by searching for characteristic features in the signals. To calculate stride length, the gravity compensated accelerometer signal was double integrated, and sensor drift was modeled using a piece-wise defined linear function. The presented method was validated using GAITRite-based gait parameters from 101 patients (average age 82.1 years). Subjects performed a normal walking test with and without a wheeled walker. The parameters stride length and stride time showed a correlation of 0.93 and 0.95 between both systems. The absolute error of stride length was 6.26 cm on normal walking test. The developed system as well as the GAITRite showed an increased stride length, when using a four-wheeled walker as walking aid. However, the walking aid interfered with the automated analysis of the GAITRite system, but not with the inertial sensor-based approach. In summary, an algorithm for the calculation of clinically relevant gait parameters derived from inertial sensors is applicable in the diagnostic workup and also during long-term monitoring approaches in the elderly population.

2P1-T09 平面正八角形構造をした劣駆動歩行ロボットの開発と基礎実験

This paper proposes a novel underactuated locomotion robot that has high stiffness and reproduces the gait property equivalent to an eight-legged rimless wheel walking on a slippery road surface. First, we describe the overview of the experimental machine we developed and its mechanical features. Second, we develop the equations of motion and collision for the ideal model with small passive rollers, and discuss the collision dynamics for stance-leg exchange with the prospect of transition to non-instantaneous double-support motion. Third, we perform numerical simulations to understand the fundamental properties of the gait rolling on a rigid road surface, and discuss its similarity to limit cycle walking on a slippery road surface.

Use of Accelerators for Biomechanical Analysis of Walking Motion Aided by Wheeled Walking Frames

Walkers improve self-reliability. We examined the effectiveness of a newly developed wheeled walking frame for use by physically handicapped persons. Unstable gaits in walker users were analyzed by tri-axial accelerometers and a motion capture system. Several markers were placed on subjects' backs and legs. Subjects were requested to walk around a test course at a comfortable speed, while their motion was recorded by two high-speed video cameras. The activities performed on the test course comprised standing, normal walking, fast walking, and walking over a barrier. Any accidental falls were also recorded. We established the characteristic rules of gait motion using a walker. Furthermore, we demonstrated that gait characteristics are more conveniently extracted from acceleration sensors than from motion capture systems, since the sensors can be affixed to subjects for self-monitoring and goal achievements. The methods employing acceleration sensors are considered suitable for determining the average gait motions of elderly persons living in nursing homes, and can be used to evaluate walking motion before and after rehabilitation.