Showing papers on "Stair climbing published in 2019"

Stair Climbing Stabilization of the HRP-4 Humanoid Robot using Whole-body Admittance Control

Abstract: We consider dynamic stair climbing with the HRP-4 humanoid robot as part of an Airbus manufacturing use-case demonstrator. We share experimental knowledge gathered so as to achieve this task, which HRP-4 had never been challenged to before. In particular, we extend walking stabilization based on linear inverted pendulum tracking [1] by quadratic programming-based wrench distribution and a whole-body admittance controller that applies both end-effector and CoM strategies. While existing stabilizers tend to use either one or the other, our experience suggests that the combination of these two approaches improves tracking performance. We demonstrate this solution in an on-site experiment where HRP-4 climbs an industrial staircase with 18.5 cm high steps, and release our walking controller as open source software.11https://github.com/stephane-caron/lipm_walking-controller/

Designing AR Visualizations to Facilitate Stair Navigation for People with Low Vision

Abstract: Navigating stairs is a dangerous mobility challenge for people with low vision, who have a visual impairment that falls short of blindness. Prior research contributed systems for stair navigation that provide audio or tactile feedback, but people with low vision have usable vision and don't typically use nonvisual aids. We conducted the first exploration of augmented reality (AR) visualizations to facilitate stair navigation for people with low vision. We designed visualizations for a projection-based AR platform and smartglasses, considering the different characteristics of these platforms. For projection-based AR, we designed visual highlights that are projected directly on the stairs. In contrast, for smartglasses that have a limited vertical field of view, we designed visualizations that indicate the user's position on the stairs, without directly augmenting the stairs themselves. We evaluated our visualizations on each platform with 12 people with low vision, finding that the visualizations for projection-based AR increased participants' walking speed. Our designs on both platforms largely increased participants' self-reported psychological security.

Classification of Gait Type Based on Deep Learning Using Various Sensors with Smart Insole.

Abstract: In this paper, we proposed a gait type classification method based on deep learning using a smart insole with various sensor arrays. We measured gait data using a pressure sensor array, an acceleration sensor array, and a gyro sensor array built into a smart insole. Features of gait pattern were then extracted using a deep convolution neural network (DCNN). In order to accomplish this, measurement data of continuous gait cycle were divided into unit steps. Pre-processing of data were then performed to remove noise followed by data normalization. A feature map was then extracted by constructing an independent DCNN for data obtained from each sensor array. Each of the feature maps was then combined to form a fully connected network for gait type classification. Experimental results for seven types of gait (walking, fast walking, running, stair climbing, stair descending, hill climbing, and hill descending) showed that the proposed method provided a high classification rate of more than 90%.

Do stair climbing exercise “snacks” improve cardiorespiratory fitness?

Abstract: We investigated the effect of stair climbing exercise “snacks” on peak oxygen uptake. Sedentary young adults were randomly assigned to perform 3 bouts/day of vigorously ascending a 3-flight stairwe...

Development of a soft knee exosuit with twisted string actuators for stair climbing assistance

Abstract: Stair climbing remains one of the toughest tasks of the elderly in activities of daily livings (ADLs). However, most of the existing stair climbing assistance devices are large and heavy, such as the automatic stair climbing wheelchair, the rigid exoskeleton and so on. They all lack applicability in the daily life. Based on this starting point, in this paper, a soft knee suit (Hitexosuit) has been developed to assist people climbing. It is a lightweight and wearable assistance suit for human lower extremity in climbing the stairs. This paper finds out the certain phase of stair climbing motion that requires the most muscle strength and locates the target muscle that contributes most when people climb the stairs through the biomechanics analysis. Furthermore, this research draws inspiration from the human muscles, which contract to generate force for knee extension and help people lift their body to go upstairs. Based on that bionic principle, a new type of artificial muscle is developed. It simulates human muscle contraction by shortening the length of steel wire to give extra strength to human lower extremity. And textiles have been adopted in the suit, soft straps and belts to make up the structure of the suit instead of rigid and heavy materials. In addition, to minimize the whole weight of the exosuit system further, we develop a lightweight and portable actuator using twisted strings. This twisted string actuator (TSA) weighs 390g and the whole exosuit weight is 3.5kg with two TSAs. The exosuit is tested with three different users and the mean assistance efficiency is 29.8%. It will improve the living quality of the aged by guaranteeing them more confidence in ADLs and self-caring.

Estimation of Heart Rate Recovery after Stair Climbing Using a Wrist-Worn Device

Abstract: Heart rate recovery (HRR) after physical exercise is a convenient method to assesscardiovascular autonomic function. Since stair climbing is a common daily activity, usually followedby a slow walking or rest, this type of activity can be considered as an alternative HRR test.The present study explores the feasibility to estimate HRR parameters after stair climbing usinga wrist-worn device with embedded photoplethysmography and barometric pressure sensors.A custom-made wrist-worn device, capable of acquiring heart rate and altitude, was used to estimatethe time-constant of exponential decay t, the short-term time constant S, and the decay of heart ratein 1 min D. Fifty-four healthy volunteers were instructed to climb the stairs at three different climbingrates. When compared to the reference electrocardiogram, the absolute and percentage errors werefound to be ≤ 21.0 s ( 52.7%) for τ, ≤ 0.14 (≤ 19.2%) for S, and ≤ 7.16 bpm (≤ 20.7%) for D in 75%of recovery phases available for analysis. The proposed approach to monitoring HRR parameters inan unobtrusive way may complement information provided by personal health monitoring devices(e.g., weight loss, physical activity), as well as have clinical relevance when evaluating the efficiencyof cardiac rehabilitation program outside the clinical setting.

Watch your step! Who can recover stair climbing independence after stroke?

Abstract: BACKGROUND After discharge, most patients who have suffered a stroke remain with some limitations in their stair climbing ability. This is a critical factor in order to be independent in real-life mobility. Although there are several studies on prognostic factors for gait recovery, few of them have focused on the recovery of stair climbing. AIM The aim of this study was to identify prognostic risk factors for the recovery of stair climbing ability in a large sample of subjects with subacute stroke. DESIGN Observational study. SETTING Neurorehabilitation Inpatient Unit. POPULATION Subjects within the first month after stroke that had been admitted to an inpatient rehabilitation unit and discharged after an intensive inpatient rehabilitation. METHODS Demographical and clinical data were collected. Barthel Index (BI), Trunk Control Test and Motricity Index (MI) scores were recorded at admission and at discharge. Patients received two daily 40-minute sessions of motor rehabilitation, six days per week, during approximately two months. Forward Binary Logistic regressions were used to identify the role of risk factors, using as dependent variables the recovery of stair climbing ability and walking ability at discharge. As independent variables we used age, gender, onset-to-admission interval, side of hemiparesis, trunk control, Motricity Index (MI), presence of obesity, presence of neglect, presence of depression, classification of cerebral infarction (total anterior circulation, partial anterior circulation, posterior circulation or lacunar infarcts), degree of independence in activities of daily living, and cognitive state, all assessed at admission. RESULTS A total of 257 subjects were enrolled. BI-Score, MI-Score and presence of unilateral spatial neglect at admission were able to explain 83% of variance for the recovery of stair climbing ability. Subjects with a BI >40 at admission were about 17 times more likely to be able to climb stairs again than other patients, and those with MI ≥25 were about 9 times more likely than the rest. The presence of unilateral spatial neglect reduced this possibility of recovering stair climbing ability by about 5.5 times. Of these factors, only MI ≥25, together with a score at Trunk Control Test >12, significantly predicted also walking recovery. CONCLUSIONS This study highlights the different prognostic factors for recovering stair climbing and walking abilities, with a major role of unilateral spatial neglect in the former. CLINICAL REHABILITATION IMPACT There is a need for specific rehabilitation of stair climbing, also for improving the independence in activities of daily living, especially in patients who the clinical staff already knows should manage stairs in their community after being discharged.

Curved-Spoke Tri-Wheel Mechanism for Fast Stair-Climbing

Abstract: Stairs are common obstacles in indoor environments and are difficult to overcome for robots. The speed of robot stair-climbing should be similar to that of humans for commercial products, but their speed remains limited. Additionally, the variety of dimensions of stairs is also a significant problem for robust stair-climbing by robots. In this paper, a curved spoke-based tri-wheel mechanism is proposed for fast and robust stair-climbing. The goal speed of stair-climbing is similar to the human speed for variously sized stairs. The proposed wheel system is composed of a tri-wheel mechanism with a curved spoke, wherein the dimensions of the mechanism are determined based on a kinematic analysis. Between the tri-wheels, a stopper mechanism acts to make the initial condition of the sequential stair-climbing the same as the initial starting condition. Static analysis to analyze the minimum friction coefficient is performed to verify the performance of the robot. Experiments based on the prototype are performed to verify the stair-climbing speed for variously sized stairs; the results indicate that fast and robust stair climbing performance is achieved. These findings can be used to design an indoor service robot for various applications.

Effects of a Brief Stair-Climbing Intervention on Cognitive Performance and Mood States in Healthy Young Adults.

Abstract: Objective: Previous studies focused on the benefits of acute exercise on cognition and mood have mostly used specialized laboratory-based equipment, thus little is known about how such protocols ge ...

Low Volume, Home-Based Weighted Step Exercise Training Can Improve Lower Limb Muscle Power and Functional Ability in Community-Dwelling Older Women.

Abstract: Stepping exercise can be used as a scalable form of high intensity exercise to enhance important aspects of physical fitness in older populations. The addition of supplementary weights increases the resistive element of stepping, with the potential for training improvements in muscular strength, power, and functional abilities alongside other fitness outcomes. The aim of this study was to evaluate the effects of a low-volume, home-based weighted step exercise programme on muscular strength, power, and functional ability in previously inactive community-dwelling older women. Eleven participants, aged between 65⁻74 years, independently completed a six-week individualised and progressive step exercise training programme wearing a weighted vest. Knee extensor strength, lower limb power output, and physical function using a battery of functional tests were measured at baseline, following a 6-week control period, and again following the 6-week training programme. Following training, lower limb power output improved by 10⁻11% (p < 0.05) and was accompanied by a corresponding 9% (p < 0.01) improvement in stair climb time and 10% (p < 0.01) improvement in normalised stair climbing power, highlighting the beneficial effects of weighted stepping for transferable improvements in functional fitness. The magnitude of observed training improvements suggest that weighted step training has the potential to prolong independence and prevent age-related health conditions such as sarcopenia.

Promoting Stair Climbing as an Exercise Routine among Healthy Older Adults Attending a Community-Based Physical Activity Program.

Abstract: Stair climbing provides a feasible opportunity for increasing physical activity (PA) in daily living. The purpose of this study was to examine the daily walking and stair-climbing steps among healthy older adults (age: 74.0 ± 4.9 years; Body Mass Index (BMI): 22.3 ± 2.5 kg/m2). Participants (34 females and 15 males) attended a weekly 6-month community-based PA program. During the entire program period, daily walking and stair-climbing steps were recorded using a pedometer (Omron, HJA-403C, Kyoto, Japan). Before and after the 6-month program, height, body weight and leg muscle strength were assessed. After the 6-month program, the mean walking and stair-climbing steps in both women and men increased significantly (p ≤ 0.01). Daily stair-climbing steps increased about 36 steps in women and 47 steps in men. At the end of 6 months, only male participants had significant correlation between the number of stair steps and leg muscle strength (r = 0.428, p = 0.037). This study reported that healthy older adults attending the community-based PA program had regular stair-climbing steps during daily living. Promoting stair climbing as an exercise routine was feasible to increase their walking and stair-climbing steps.

Robot-Assisted Stair Climbing Training on Postural Control and Sensory Integration Processes in Chronic Post-stroke Patients: A Randomized Controlled Clinical Trial.

Abstract: Background: Postural control disturbances are one of the important causes of disability in stroke patients affecting balance and mobility. The impairment of sensory input integration from visual, somatosensory and vestibular systems contributes to postural control disorders in post-stroke patients. Robot-assisted gait training may be considered a valuable tool in improving gait and postural control abnormalities. Objective: The primary aim of the study was to compare the effects of robot-assisted stair climbing training against sensory integration balance training on static and dynamic balance in chronic stroke patients. The secondary aims were to compare the training effects on sensory integration processes and mobility. Methods: This single-blind, randomized, controlled trial involved 32 chronic stroke outpatients with postural instability. The experimental group (EG, n = 16) received robot-assisted stair climbing training. The control group (n = 16) received sensory integration balance training. Training protocols lasted for five weeks (50 min/session, two sessions/week). Before, after, and at 1-month follow-up, a blinded rater evaluated patients using a comprehensive test battery. Primary outcome: Berg Balance Scale. Secondary outcomes:10-meter walking test, 6-minute walking test, Dynamic gait index, stair climbing test up and down, the Time Up and Go, and length of sway and sway area of the Center of Pressure (CoP) assessed using the stabilometric assessment. Results: There was a non-significant main effect of group on primary and secondary outcomes. A significant Time×Group interaction was measured on 6-minute walking test (p= 0.013) and on posturographic outcomes (p=0.005). Post hoc within-group analysis showed only in the EG a significant reduction of sway area and the CoP length on compliant surface in the eyes-closed and dome conditions. Conclusion: Postural control disorders in patients with chronic stroke may be ameliorated by robot-assisted stair climbing training and sensory integration balance training. The robot-assisted stair climbing training contributed to improving sensorimotor integration processes on compliant surfaces. Clinical trial registration (NCT03566901).

Gait Analysis Reveals that Total Hip Arthroplasty Increases Power Production in the Hip During Level Walking and Stair Climbing.

Abstract: BACKGROUND total hip arthroplasty (THA) is associated with decreased pain and improved function, including increased walking speed, but it does not always improve overall joint mechanics during activities of daily living such as level walking and stair climbing. The hip's ability to generate power to move and allow for smooth and efficient forward motion is critical to success after surgery. Although osteoarthritis (OA) of the hip limits the power of the affected joint, it is not known whether other joints in the affected limb or in the contralateral limb need to produce more power to compensate. Additionally, it is not known whether alterations in the production of power before and after surgery are gender-specific. QUESTIONS/PURPOSES (1) Is there a change in the power production of the bilateral ankles, knees, and hips during level walking before and after patients undergo unilateral THA, and are there important gender-specific differences in these findings? (2) How do these findings differ for stair climbing? METHODS Three-dimensional motion and ground reaction force data were collected for 13 men and 13 women who underwent primary, unilateral THA. This was a secondary analysis of previously collected data on gait mechanics from 60 patients who underwent THA. In the initial study, patients were included if they were scheduled to undergo a primary, unilateral THA within 4 weeks of the study and were able to walk without an assistive device. Patients were recruited from the practices of four surgeons at a single institution from 2008 to 2011. Patients were included in the current study if they were enrolled in the previous study, attended all three assessment visits (preoperative and 6 weeks and 1 year postoperative), and, during the preoperative visit, were able to walk without using an assistive device and climb stairs without using a handrail. Patients walked and ascended stairs at a self-selected speed at the three assessment visits. The power of each ankle, knee, or hip was calculated in Visual 3D using kinematic and kinetic data collected using motion capture. Power for each joint was normalized to the total power of the bilateral lower limbs by dividing the individual joint power by the total lower-extremity joint power. A mixed-model repeated-measures ANOVA was used to determine differences in normalized joint power for the ankle, knee, and hip, based on gender, limb (surgical-side versus nonsurgical-side) and timepoint (preoperative and 6 weeks and 1 year postoperative). RESULTS Surgical-side absolute (preoperative: -0.2 ± 0.2 [CI, -0.3 to -0.2], 1 year postoperative: -0.5 ± 0.3 [CI, -0.6 to - 0.5]; p < 0.001) and normalized (preoperative: 0.05 ± 0.04 [CI, 0.03-0.06], 1 year postoperative: 0.08 ± 0.04 [CI, 0.06-0.09]; p = 0.020) hip power production increased during walking. Surgical-side absolute (preoperative: 1.1 ± 0.3 [CI, 1.0-1.3], 1 year postoperative: 1.6 ± 0.2 [CI, 1.3-2.0]; p = 0.005) and normalized (preoperative: 0.16 ± 0.04 [CI, 0.14-0.18], 1 year postoperative: 0.21 ± 0.06 [CI, 0.18-0.24]; p = 0.008) hip power production increased during stair climbing, while nonsurgical ankle absolute (preoperative: 0.9 ± 0.5 [CI, 0.6 - 1.2], 1 year postoperative: 0.6 ± 0.3 [CI, 0.4-0.8]; p = 0.064) and normalized (preoperative: 0.13 ± 0.06 [CI, 0.10-0.16], 1 year postoperative: 0.08 ± 0.04 [CI, 0.06-0.10]; p = 0.015) power decreased during stair climbing after THA. No consistent effect of gender was observed. CONCLUSIONS In this gait-analysis study, power was improved in hip joints that were operated on, and power production in the ipsilateral and contralateral ankles and ipsilateral hips was reduced during level walking and stair climbing. The success of surgical intervention must be based on restoring reasonable balance of forces in the lower limb. Patients with OA of the hip lose power production in this joint and must compensate for the loss by producing power in other joints, which then may become arthritic. To determine future interventions, an understanding of whether changes in forces or joint angle affect the change in joint power is needed. Based on these results, THA appeared to effectively increase hip power and reduce the need for compensatory power production in other joints for both men and women in this patient cohort. LEVEL OF EVIDENCE Level I, prognostic study.

One-minute stair climbing, 50-foot walk, and timed up-and-go were responsive measures for patients with chronic low back pain undergoing lumbar fusion surgery

Abstract: Physical capacity tasks are useful tools to assess functioning in patients with low back pain (LBP), but evidence is scarce regarding the responsiveness (ability to detect change over time) and minimal important change (MIC). The aim was to investigate the responsiveness and MIC of 5-min walk, 1-min stair climbing, 50-ft walk, and timed up-and-go in patients with chronic LBP undergoing lumbar fusion surgery. In this clinimetric study, 118 patients scheduled for lumbar fusion surgery for motion-elicited chronic LBP with degenerative changes were included. All patients performed the physical capacity tasks 5-min walk, 1-min stair climbing, 50-ft walk, and timed up-and-go 8–12 weeks before and six months after surgery. Responsiveness was evaluated by testing five a priori responsiveness hypotheses. The hypotheses concerned the area under the receiver operating characteristics (ROC) curve and correlations (Spearman’s rho) between the change scores of the physical capacity tasks, the Oswestry Disability Index 2.0 (ODI), and back pain intensity measured with visual analog scale (VAS). At least 80% of the hypotheses would have to be confirmed for adequate responsiveness. Absolute and relative MICs for improvement were determined by the optimal cut-off point of the ROC curve based on the classification of improved and unchanged patients according to construct-specific global perceived effect (GPE) scales. One-minute stair climbing, 50-ft walk and timed up-and-go displayed adequate responsiveness (≥ 80% of hypotheses confirmed), while 5-min walk did not (40% of hypotheses confirmed). The absolute MICs for improvement were 45.5 m for 5-min walk, 20.0 steps for 1-min stair climbing, − 0.6 s for 50-ft walk, and − 1.3 s for timed up-and-go. The results of responsiveness for 1-min stair climbing, 50-ft walk, and timed up-and-go implies that these have the ability to detect changes in physical capacity over time in patients with chronic LBP who have undergone lumbar fusion surgery.

Whole-Body Motion and Landing Force Control for Quadrupedal Stair Climbing

Abstract: In this paper, we present a novel framework for quadrupedal stair climbing, which considers force interaction with stairs. For stable and robust climbing, a key issue is to avoid falling down on the stairs. From this point of view, control to minimize rate of change of angular momentum about Center of Mass (CoM) which is produced by ground reaction force (GRF) at contact of robot‘s foot is necessary. Using this approach, direct force-based Zero Moment Point (ZMP) for motion planning of the CoM and landing force control are implemented. The direct force-based ZMP method allows the robot to lift its foot with reduced possibility of tilting on the stairs, and the landing force control prevents instant increase of the moment by impact of the GRFs. In addition, terrain recognition to estimate parameters of the stairs and find proper footholds by vision system mounted on the robot is presented. Proposed framework is implemented to quadruped robot, AiDIN-VI, that has torque sensor at each joint, through experiments, capability of ascending several stairs including 3step stairs which have 21cm height (31% of its maximum leg length) and 26.5° inclination is validated.

Design and fabrication of a lower limb exoskeleton to assist in stair ascending

Abstract: This paper aims to deal with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.,For this purpose, a novel design of a mixture of motors and cables has been proposed for users to wear them easily and show the application of the system in stair climbing.,One of the prominences of this study is the provided robot design where four joints are actuated with only two motors; each motor actuates either the knees or ankles. Another advantage of the designed system is that with motors placed in a backpack, the knee braces can be worn under clothes to be concealed. Finally, the system performance is evaluated using electromyography (EMG) signals showing 28 per cent reduction in energy consumption of related muscles.,This investigation deals with the development of a novel lower limb exoskeleton to assist disabled people in stair ascending.

Bicruciate Substituting Total Knee Arthroplasty Improves Stair Climbing Ability When Compared with Cruciate-Retain or Posterior Stabilizing Total Knee Arthroplasty

Abstract: Purpose: The purpose of this study was to compare stair climbing and descent ability following bicruciate substituting (BCS), cruciate retaining (CR), and posterior stabilizing (PS) total knee arthroplasties (TKAs). Materials and Methods: Sixty-three participants undergoing BCS-TKA (journey II: Smith and Nephew), 47 participants undergoing CR-TKA (FINE: Teijin Nakashima Medical), and 38 participants undergoing PS-TKA (FNK: Teijin Nakashima Medical) were included in this study. Before and 12 months after surgery, a questionnaire was administered to assess daily stair climbing and descent ability. In the questionnaire, stair climbing and descent ability were classified as (1) stair climbing and descent one step at a time, (2) stair climbing and descent two steps at a time, and (3) unable to climb or descend stairs. The necessity of a handrail was also evaluated and classified as: (1) necessary, (2) unnecessary, and (3) unable to climb or descend stairs with handrail. Statistical analysis (χ2-test) was performed to compare these data between the types of TKA. Results: Preoperatively, no significant differences in stair climbing and descent ability or between handrail classifications were observed between the three different TKA groups. Postoperatively, the percentage of patients able to climb stairs one step at a time was significantly higher in BCS-TKA group (89%), when compared with CR (72%) or PS (58%) TKA groups. No significant differences in stair descent ability or among the handrail necessity classifications were observed between the types of TKA. Conclusion: BCS-TKA resulted in significantly better stair climbing ability when compared with CR or PS-TKA. This may indicate that the design of BCS-TKA better reproduces native anterior cruciate ligament and posterior cruciate ligament function and improves knee stability during stair climbing activity.

Design of a robust stair-climbing compliant modular robot to tackle overhang on stairs

Abstract: This paper discusses the concept and parameter design of a robust stair-climbing compliant modular robot, capable of tackling stairs with overhangs. Geometry modifications of the periphery of the wheels of our robot helped in tackling overhangs. Along with establishing a concept design, the robust design parameters are set to minimize performance variations. The Grey-based Taguchi method is applied to provide an optimal setting for the design parameters of the robot. The robot prototype is shown to have successfully scaled stairs of varying dimensions, with overhang, thus corroborating the analysis performed.

EMG Muscle Activation Pattern of Four Lower Extremity Muscles during Stair Climbing, Motor Imagery, and Robot-Assisted Stepping: A Cross-Sectional Study in Healthy Individuals.

Abstract: Background. Stair climbing can be a challenging part of daily life and a limiting factor for social participation, in particular for patients after stroke. In order to promote motor relearning of stair climbing, different therapeutical measures can be applied such as motor imagery and robot-assisted stepping therapy. Both are common therapy measures and a positive influence on the rehabilitation process has been reported. However, there are contradictory results regarding the neuromuscular effect of motor imagery, and the effect of robot-assisted tilt table stepping on the EMG activation compared to stair climbing itself is not known. Thus, we investigated the EMG activity during (1) a stepping task on the robot-assisted tilt table Erigo, (2) motor imagery of stair climbing, and (3) real stair climbing in healthy individuals for a subsequent study on patients with lower limb motor impairment. The aim was to assess potential amplitude independent changes of the EMG activation as a function of the different conditions. Methods. EMG data of four muscles of the dominant leg were recorded in m. rectus femoris, m. biceps femoris, m. tibialis anterior, and m. gastrocnemius medialis. The cross-correlation analysis was performed to measure similarity/dissimilarity of the EMG curves. Results. The data of the study participants revealed high cross-correlation coefficients comparing the EMG activation modulation of stair climbing and robot-assisted tilt table stepping in three muscles except for the m. gastrocnemius medialis. As the EMG activation amplitude did not differ between motor imagery and the resting phase the according EMG data of the motor imagery condition were not subjected to a further analysis. Conclusion. Robot-assisted tilt table stepping, but rather not motor imagery, evokes a similar activation in certain leg muscles compared to real stair climbing.

The effects of abdominal drawing-in maneuver during stair climbing on muscle activities of the trunk and legs.

Abstract: The purpose of this study was to investigate effects of abdominal drawing-in maneuver (ADIM) on the muscular activity of the trunk and the lower limbs during stair ascent. The subjects were healthy 15 men and 8 women who were in their 20s. After maintaining ADIM by using a pressure biofeedback unit for 15 min, the subjects performed stair ascent and their muscular activity of the right trunk and the legs was measured to determine difference between when the subjects maintained ADIM and did not. The activities of the sternocleidomastoid, the splenius capitis, the rectus abdominis (ABD), the external abdominal oblique (EO), the transverse abdominis (TRA), the elector spinae (ES), the vastus medialis (VM), and the vastus lateralis (VL) were measured using surface electromyogram (TM DTS). The collected data were statistically processed by the SPSS ver. 18.0 and analyzed with a paired t-test. The muscular activities of the TRA, VM, and VL significantly increased (P<0.05), while the activity of the ES significantly decreased (P<0.05) during stair ascent when the ADIM was maintained than when it was not. In conclusion, the stair ascent with ADIM maintained activated the abdominal muscles to control trunk balance and perform lumbar stability, simultaneously reducing excessive lumbar lordosis or pelvic anterior tilt which will help to improve the function of the musculoskeletal system.

Optimal Stair Climbing Pattern Generation for Humanoids Using Virtual Slope and Distributed Mass Model

Abstract: This study addresses optimal walking pattern generation for SURENA III humanoid robot in a stair-climbing scenario. To this end, the kinematic configuration of the 31-DOF humanoid robot is studied. Integrating the detailed dynamic properties of the robot, a comprehensive and precise dynamic model is developed for its lower-limb. In order to generate the optimal walking pattern for the considered humanoid robot, trajectories for feet and pelvis are first designed, and then joint angles are derived by means of inverse kinematics. Such a complete model provides the designer with the necessary tools to optimize the trajectory generation. Using two different types of objective functions, namely joints maximum torque and overall energy consumption, several optimization processes have been carried out to account for different stair-climbing speeds as well as different stair heights. Subsequently, the optimal walking patterns are obtained by applying the Genetic Algorithm (GA). The simulation results are verified experimentally by implementing the proposed walking patterns on SURENA III, a humanoid robot designed and fabricated in CAST (Center of Advanced Systems and Technologies). This paper provides insight into how an optimized gait for climbing stairs can be realized for a human-size humanoid robot from two different viewpoints and at several walking speeds and stair heights by assuming each stair as a virtual slope.

Signage Interventions for Stair Climbing at Work: More than 700,000 Reasons for Caution.

Abstract: Increased stair climbing reduces cardiovascular disease risk. While signage interventions for workplace stair climbing offer a low-cost tool to improve population health, inconsistent effects of intervention occur. Pedestrian movement within the built environment has major effects on stair use, independent of any health initiative. This paper used pooled data from UK and Spanish workplaces to test the effects of signage interventions when pedestrian movement was controlled for in analyses. Automated counters measured stair and elevator usage at the ground floor throughout the working day. Signage interventions employed previously successful campaigns. In the UK, minute-by-minute stair/elevator choices measured effects of momentary pedestrian traffic at the choice-point (n = 426,605). In Spain, aggregated pedestrian traffic every 30 min measured effects for 'busyness' of the building (n = 293,300). Intervention effects on stair descent (3 of 4 analyses) were more frequent than effects on stair climbing, the behavior with proven health benefits (1 of 4 analyses). Any intervention effects were of small magnitude relative to the influence of pedestrian movement. Failure to control for pedestrian movement compromises any estimate for signage effectiveness. These pooled data provide limited evidence that signage interventions for stair climbing at work will enhance population health.

Deep Learning-Based Stair Segmentation and Behavioral Cloning for Autonomous Stair Climbing

Abstract: Mobile robots are widely used in the surveillance industry, for military and industrial applications. In order to carry out surveillance tasks like urban search and rescue operation, the ability to...

Differentiating Between Walking and Stair Climbing Using Raw Accelerometry Data.

Abstract: Wearable accelerometers provide an objective measure of human physical activity. They record high frequency unlabeled three-dimensional time series data. We extract meaningful features from the raw accelerometry data and based on them develop and evaluate a classification method for the detection of walking and its sub-classes, i.e. level walking, descending stairs and ascending stairs. Our methodology is tested on a sample of 32 middle-aged subjects for whom we extracted features based on the Fourier and wavelet transforms. We build subject-specific and group-level classification models utilizing a tree-based methodology. We evaluate the effects of sensor location and tuning parameters on the classification accuracy of the tree models. In the group-level classification setting, we propose a robust feature inter-subject normalization and evaluate its performance compared to unnormalized data. The overall classification accuracy for the three activities at the subject-specific level was on average 87.6%, with the ankle-worn accelerometers showing the best performance with an average accuracy 90.5%. At the group-level, the average overall classification accuracy for the three activities using the normalized features was 80.2% compared to 72.3% for the unnormalized features. In summary, a framework is provided for better use and feature extraction from raw accelerometry data to differentiate among different walking modalities as well as considerations for study design.

Characteristics of a Lower Limb Exoskeleton for Gait and Stair Climbing Therapies

Abstract: The first exoskeleton development in Peru was performed at Pontificia Universidad Catolica del Peru (PUCP), supported by health professionals, with the aim of treating locomotion disability which is the second main limitation affecting Peruvians these days. It is a lower limb exoskeleton for assisting normal gait and stair climbing in the sagittal plane whose dynamic model was obtained from data collected from over 40 Peruvian young adults. The proposed mechanical design is a hip-knee-ankle device that is electrically actuated and which also allows for passive rotation of hip and ankle in the frontal plane. Additionally, the system includes a trolley and a telescopic guide which allow for horizontal and vertical movement of patient’s center of mass; therefore, these parameters can also be controlled in order to obtain customized therapies. Currently, a simplified model of this design is being implemented in order to verify exoskeleton proper behavior and its response to control system commands.