Riding Posture Research Articles

Design and Optimization of Multifunctional Human Motion Rehabilitation Training Robot EEGO

A multifunctional human motion rehabilitation training robot named EEGO (electric easy go) that could achieve four functions through structural transformation was designed. The four functions achieved by four working modes: the Supporting Posture Mode (SM), the Grasping Posture Mode (GM), the Riding Posture Mode (RM), and the Pet Mode (PM), which are suitable for patients in the middle and late stages of rehabilitation. The size of the equipment under different functions is determined by the height of different postures of the human. During the design process, the equipment was lightweight using size optimization methods, resulting in a 47.3% reduction in mass compared to the original design. Based on the Zero Moment Point (ZMP) stability principle, the stability mechanism of the robot was verified under the three different functions. According to the wanted function of the equipment, the control system of the equipment was designed. Finally, a prototype was prepared based on the analysis and design results for experimental verification, which can effectively assist patients in motion rehabilitation training such as gait, walking, and other movements.

Effectiveness of a 3D bikefitting method in riding pain, fatigue, and comfort: a randomized controlled clinical trial

ABSTRACT To investigate the effects of bike fitting compared to qualitative-based riding posture recommendations on comfort, fatigue, and pain in amateur cyclists. This was a randomised controlled parallel trial of 162 amateur cyclists divided into two groups: bike fitting group (BFG) – participants received a bike fitting session based on 3D kinematic assessments; and a control group (QG) – participants who received a handout containing qualitative-based cycling posture recommendations. Primary outcomes were perceived comfort (FEEL Scale), perceived fatigue (OMNI Scale), and perceived pain (numeric rating pain scale, NRPS). Outcomes were assessed at baseline, when the interventions were delivered, and after 15 days. Intention-to-treat analyses were conducted using student t-tests between pre and post intervention on both groups. All dependent variables from BFG displayed significant statistical difference between both groups post-intervention (p < 0.05). FEEL Scale and OMNI Scale results showed the highest changes of all variables under analysis (mean differences of 3.12 and 3.95 points, respectively); while the body parts with more reduction in riding pain were Groin and Back (mean differences of 1.68 and 1.35, respectively). In conclusion, 3D kinematic bikefit demonstrated superior improvements over riding pain, comfort and fatigue compared to qualitative riding posture recommendations.

Long-Term Effects of a Kinematic Bikefitting Method on Pain, Comfort, and Fatigue: A Prospective Cohort Study.

Highlights What are the main findings? Pain and comfort levels improved after bikefit and remained stable through 4 months.Even with discrete increase after 3 months, fatigue levels remained significantly lower. What is the implication of the main findings? Ergonomic adjustments through bikefitting improves riding experience for a long period of time, and it can contribute to increase cycling adhesion.With increased riding comfort and reduced pain, participants showed increased fatigue and mileage levels, indicating increased sports practice. The purpose of this study is to analyze the long-term riders’ subjective responses to a standardized bikefitting method on their bicycles. Eighty-six amateur mountain bikers had their riding posture and bicycle components ergonomically adjusted through a 3D kinematic bikefitting method. Validated subjective scales (Feeling, OMNI, and Numerical Rating Pain Scale) were used to assess their overall riding comfort and fatigue along with localized pain for six body parts. Data were collected just before intervention (baseline or pre), immediately after (or post), and 30, 60, 90, and 120 days after the bikefit session. A Student’s t-test comparing before bikefit and after 120 days showed significant (p < 0.05) reduction in localized pain for all six body parts and riding comfort along with a large effect size effect (d = 1.18) for riding comfort. Although initially reduced, fatigue scores gradually increased over the months, showing a high correlation (r = 0.946) with increased monthly training volume. In conclusion, overall riding discomfort and pain were significantly decreased after a standardized kinematic bikefit session even after 120 days post intervention. However, fatigue scores began to rise after 30 days, showing a high correlation with increasing monthly training volume.

The Influence of the Inter-Relationship of Leg Position and Riding Posture on Cycling Aerodynamics

Aerodynamics is an important factor affecting cyclist performance, as at the elite level 90% of rider energy is used to overcome aerodynamic drag. As such, much effort has been channeled into understanding the detailed flow around cyclists, since small gains can produce large rewards. Previous studies have shown that cycling aerodynamic drag is sensitive to leg position during the pedaling cycle; however, a systematic analysis comparing the impact of leg position between different riding postures is yet to be undertaken. To address this question, we compare the impact of leg position for two elite-level riding postures: the standard sprint and pursuit body positions. The comparison shows that the effect of leg position on drag is not consistent between the two riding postures, as the altered flow associated with different leg positions is influenced by the wakes from and proximity of other upstream or nearby components, such as the arms. This study reveals the inter-relationship between leg position and riding posture; and suggests that the flow associated with varied leg position should include surrounding geometrical components to obtain and understand the full aerodynamic impact. Practically, the results are valuable for optimizing the posture and improving skin-suit design for drag minimization.

Exploring the association of riders’ physical attributes with comfortable riding posture and optimal riding position

In recent years, there has been a keen interest in the design improvisation of motorcycles. However, the theoretical model of association between motorcycle design attributes (like frame size/riding position) and rider’s physical attributes (like anthropometry, range of motion (ROM), and comfort joint angles) are not well established. This study aims to estimate the relationship between rider’s physical attributes and motorcycle design attributes. During this experimental study, the data was collected from 120 motorcyclists (aged between 19 and 44 years) belonging to 20 major states of India. A test-rig was fabricated to obtain the perceived comfort posture and position data using image processing technique. The anthropometry and ROM were manually measured and verified by reliability testing. The principal component analysis (PCA) and multiple linear regression were used to reduce the set of variables and estimate the relationship between 10 comfortable riding position and joint angles (as dependent variables), and the reduced set of 29 anthropometry and 20 ROM measurements (as the independent variables). These results indicate that the comfort joint angles and riding position were significantly associated with the anthropometrics and ROM of the riders. Highly significant regression models were formulated to examine the relationship between the comfort joint angles/riding position and the anthropometrics and ROM of the riders. The findings may support the motorcycle designers to design a comfortable motorcycle complying with Indian anthropometry and ROM.

Perceived comfortable posture and optimum riding position of Indian male motorcyclists for short-duration riding of standard motorcycles

Dimensional incompatibility between rider and motorcycle is one of the most causative factors responsible for the prevalence of musculoskeletal discomfort among motorcyclists. The present study aims to identify the comfortable riding posture (CRP) and optimum riding position (ORP) for improving motorcycle design for better riding experience. The data (through image processing technique) was acquired from 120 Indian male motorcyclists (aged 19–40 years) using a static simulator test-rig. The CRP was achieved by adjusting three controls (handgrip, seat, and footrest of the test-rig), and perceived comfort and discomfort ratings. Weighed mean comfort joint angles of ten body-joints defining CRP were estimated and compared with the earlier studies. The best possible ORP among the nine test conditions (defined by the positions of the three controls) was estimated using Taguchi DOE. The study outcomes will help automobile designers to conceptualize the comfortable standard motorcycles.

Assessment of ergonomic risk factors in occupational motorcycle riding: an experimental investigation

Today, the use of motorcycles has increased in the e-commerce sector for the delivery of fast food, courier or parcels, etc. The associated risk of discomfort exists here, due to long hours of exposure. For the ergonomic risk factors assessment, an experimental simulation of motorcycle riding from an occupational point of view was planned. In this, participants were invited to ride the motorcycle for 25 min at an average speed of 30 km/h for different riding postures depending on the geometry of the motorcycles. Whole body vibration (WBV) has been shown to be a major ergonomic risk factor as per the ISO 2631-1 assessment. The WBV exposure level found to be exceeding the upper limit of the health guideline caution zone (HGCZ) of ISO 2631-1 by more than five times. WBV exposure was higher for the slightly forward lean riding posture motorcycle than for the upright erect riding posture motorcycle. In addition, upper body muscle activities have shown that the slightly forward lean posture had higher muscular activity than the upright erect posture. Ergonomic interventions can reduce the risk of work-related musculoskeletal disorders (WMSDs) to delivery workers if implemented.

Analysis of the Riding Posture of Bicyclists and Influence Parameters on the Helmet Use

In the scope of COST Action TU1101 a field study of the use of bicycle helmets was carried out and different seating positions of the human body on the cycle were analyzed from photos to identify the vertical vision limit due to the helmet geometry of the cyclists when riding a bicycle. It could be interesting to know if different helmet postures will influence the resulting head impact and head injury situation and which influence parameters are responsible for the decision of the cyclist to use or not to use a helmet. For the study helmet users are compared with non-helmet users, distinguished for different bicycle types. For this purpose a total of 1565 cyclists with and without helmets were photographed and relevant geometrical values such as the angle between seat and handle bar, the decline of the torso or the head posture and the angle of the vertical vision limit were established from the photo analysis. A significant variation of the sitting posture of the cyclist could be seen in field which is influenced by the bicycle type and the age group of the cyclist riding the bike. Even the helmet users showed slight differences in the head posture compared to non-helmet users.

A REVIEW ON ENHANCING HUMAN-MACHINE-ENVIRONMENT INTERFACE FOR POSTURA MOTERGOTM

In this era of critical traffic congestion, motorcycles have become one of the popular go-to vehicles. Recently, there are several motorcycle simulators that was developed by several group researchers around the world due to the statistics of motorcycle road accidents globally alarming. They are developed for 2 different purposes which are as testing on prototype models prior to mass production and also as conducting a study on human skills and behaviour in specific motorcycling conditions. The aim of this study was to review several issues detected with respect to the currently available motorcycle simulators. In addition, a special attention was given to a motorcycle test rig named the Postura MotergoTM. The Postura MotergoTM is a new revolutionary motorcycle test rig which was developed based on Riding Posture Classification (RIPOC) system. However, it is noticeable that the current design of Postura MotergoTM could be improved to further elevate users’ experience. Other than adding to better fidelity of the motorcycle test rig, further improvements with respect to design, functionality and users’ experience would ensures the design longevity and overall cost effectiveness provided by the particular motorcycle test rig. Thus, enables the particular motorcycle test rig to contribute to various motorcycle ergonomics researches in the near future. Such matter would then be hope to ultimately aid in reducing the global motorcycle road accident statistics.

SELECTION OF MUSCLE GROUPS FOR SURFACE ELECTROMYOGRAPHY (SEMG) MEASUREMENT IN ANALYZING MOTORCYCLING ACTIVITY

While riding motorcycle have become a popular mode of transportation in most parts of the world, increase in motorcycle road accidents are very alarming. Many factors have been found to cause such motorcycle accidents and among others is motorcyclist fatigue. The aim of this study is to identify muscle groups that are related to motorcycling activity that may lead to motorcyclist muscle fatigue especially during prolonged riding. The groups of muscle recommended by this study were extracted from current literatures and studies, questionnaires and direct observation, and also a pilot surface electromyography (sEMG) experiment. Direct observation was made on motorcyclists’ hand and foot positioning during riding including their riding posture. Upon confirming the recommended muscle groups, a sEMG experiment was conducted using an established adjustable motorcycle test rig, the Postura MotergoTM. Several torso muscle groups were identified and recommended for analyzing motorcyclist muscle fatigue. However, lower extremity body muscle groups were not listed. This is due to no considerations were made by neither researchers nor being testified by participants answering the questionnaire.

Applying riding-posture optimization on bicycle frame design

Customization design is a trend for developing a bicycle in recent years. Thus, the comfort of riding a bike is an important factor that should be paid much attention to while developing a bicycle. From the viewpoint of ergonomics, the concept of “fitting object to the human body” is designed into the bicycle frame in this study. Firstly, the important feature points of riding posture were automatically detected by the image processing method. In the measurement process, the best riding posture was identified experimentally, thus the positions of feature points and joint angles of human body were obtained. Afterwards, according to the measurement data, three key points: the handlebar, the saddle and the crank center, were identified and applied to the frame design of various bicycle types. Lastly, this study further proposed a frame size table for common bicycle types, which is helpful for the designer to design a bicycle.

Male vs. Female Horse Riders: Differences in Musculoskeletal Response to the Force Generated by a Horse at the Trot

Anatomic differences in the bony pelvis and lumbar spine of male and female riders affect their riding postures. We have previously shown that the vertical force from the horse is directed toward the bodies of the lumbar vertebrae and intervertebral discs in males, but toward the zygapophyses and pedicles, an area less well-suited for force distribution, in females. The purpose of this study was to detail more specifically the forces generated by the muscles of a male and female rider in response to the force from the horse. Analysis of the classical riding posture in two phases (P1, P2) of the trot revealed: (1) In P1 of the trot, the torque from the horse affects the thorax, but not hip, of the female. It affects both in the male, who thus recruits the longissimus thoracis muscle for counterbalance. (2) In P1 of the trot, the psoas muscle is more vertically-oriented in the female, and thereby less capable than that of the male in creating forward movement of the lumbar spine. (3) The male generates relatively larger muscle forces in response to the same force from the horse in both phases, but in P1 the female iliacus muscle generates a force almost as large as that of the male, demonstrating its relative importance in the female. A better understanding of the functional consequences of such sexual dimorphisms allows riders to adapt their techniques to increase their effectiveness and decrease the potential for discomfort and injury.

Aerodynamic drag interactions between cyclists in a team pursuit

Performance in cycling events is strongly dependent on aerodynamic drag due to the high proportion of resistance that it contributes. The drag of individual cyclists has been shown to vary with riding posture and the drag of cyclists travelling in close proximity will vary as a function of separation distance. However, the influence of riding posture and the interplay between cyclists in a team is a complex problem that is not well understood. This study aims to develop a better understanding of the aerodynamic drag interactions between cyclists riding in a team as a function of their riding position. A team of four athletes was tested in the Monash University Wind Tunnel using a bespoke force balance that can measure drag on all four athletes simultaneously. Compared to an individual rider, the four riders in a team experienced mean drag savings of 5, 45, 55 and 57 % in positions 1, 2, 3 and 4 of the team, respectively. The results of individual athlete tests were shown to be a good indicator of drag response when applied in a team environment. Strong aerodynamic interactions were observed between the riders in a pursuit team. However, these varied significantly and appear to be unique functions of individual athlete body shape. Given the small winning margins at the elite level, a detailed understanding of the interactions between riders will deliver a performance edge. However, it appears necessary to test the actual athletes in situ to fully optimise performance as general trends were not consistent.

The Motorcycle Design Parameter Database (MDPD) for Different Motorcycle Models

Globally, motorcycle road accidents are increasing annually. Among the efforts in overcoming this dire scenario, motorcycle simulators were developed. The Postura MotergoTM which was developed by researchers at the Motorcycle Engineering Technology Lab (METAL) is an example of such simulators. The Postura MotergoTM has a unique capability in replicating various riding postures according to the Riding Posture Classification (RIPOC) system. However, there is the need for a novel database that gives information on the workstation design parameters of various motorcycles. Hence, a specifically built mannequin (the D5EM110N) was developed as a tool to measure various workstation dimensions on actual motorcycles. As of April 2015, the mannequin's design is being filed for an intellectual property (IP) protection. The motorcycles’ design parameters which were collected via the D5EM110N mannequin was then tabulated into the Motorcycle Design Parameter Database (MDPD). The database is then could be utilized to set up the Postura MotergoTM to accurately replicate the desired motorcycle model's workstation design parameters. This is vital in ensuring that the motorcycle simulator could accurately simulate an immersive user experience to the subject in utilizing the desired motorcycle model. By having this novel database and mannequin design, researchers have greater opportunity in conducting various studies in a controlled laboratory setting with respect to motorcycle workstation designs and its possible connection with road accidents.

B-8 荷重計測に基づいた自転車乗車時のハンドル把持位置の推定(サイクリング1)

Riding posture as well as leg motion is very important for cycling. To improve riding skills, it is very useful for riders to show their riding posture during cycling. In this study, we aim for developing a method to estimate a rider's posture only using sensors attached to a bicycle or the rider. For the first step, we propose a method to estimate hand grip position. The method uses Support Vector Machine based on the observed data from a 6-axis force/torque sensor installed at an ahead stem. Through the experiments, our estimation method achieved both high precision and high recall.

승마 숙련도에 따른 기승자세 교정효과의 운동학적 분석

The purpose of this study was to analyse the effect of posture correction & stabilization according to horse rider's(n=10) skill levels of novice(0wk), mid-skill(12wk) & skill(24wk) in walk & trot. First, Mean posture of 3 times experiments; Anterior & posterior leaning posture of trunk showed rather unstable according to progress of the stages of TD1, TO, TD2 phase, and also shoulder & elbow angle, which effects to the distance from bit to rein, showed unstable riding posture. There was close relationship between shoulder and elbow Angle in walk and hip, knee & ankle angle in trot. Second, Posture correction & stabilization according to riding skill levels; Anterior & posterior leaning posture of trunk did not show significant difference statistically but showed approaching tendency to trunk's vertical line and showed significant difference(p<.05) according to improvement of skill levels in walk & trot horse riding. Hip angle showed significant difference according to progress of the stages of TD1, TO, TD2 phase(p<.05) and showed tendency maintaining the larger thigh flexion according to improvement of skill levels in walk & trot. Knee angle showed more stable posture by maintaining the larger flexion between thigh and shank according to improvement of skill levels in walk & trot(p<.05). Ankle angle also showed tendency maintaining the larger plantar flexion of foot according to improvement of skill levels in walk & trot. When considering the above, regular horse riding program could be useful in posture correction & stabilization according to improvement of skill levels of novice(0wk), mid-skill(12wk) & skill(24wk) in walk & trot.

Motorcyclist's Riding Discomfort in Malaysia: Comparison of BMI, Riding Experience, Riding Duration and Riding Posture

AbstractThere is very little (or no) information about the riding discomfort of motorcyclists in Malaysia. Therefore, this study was done with the intention of highlighting the relationship of the discomfort on the motorcyclist's body parts during the riding process concerning factors such as body mass index (BMI), riding experience, riding hours, and preferred riding posture. This study (questionnaire survey) was done by using 957 respondents (481 males and 476 females) with an age range from 18 years to 24 years, which was collected from a previous study. The results indicate that the majority of motorcyclists who participated in this study are in the normal BMI category. However, the majority of these motorcyclists suffer discomfort in their body parts during the riding process. It is noticeable that the majority of female motorcyclists started with higher discomfort symptoms concerning the corresponding factors (BMI, riding hours, and riding experience) compared with male motorcyclists. Most male discomfort symptoms were focused on the buttock and upper body parts, whereas the female motorcyclists experienced discomfort in all of their body parts (lower, buttocks, and upper body parts). Furthermore, the results also highlight that the motorcyclists' discomfort was correlated with riding posture. Therefore, this study clearly identified that motorcyclists experience discomfort in their body parts during the riding process. The findings also highlight that the current interaction of humans (motorcyclists) and machine (motorcycle) is not an ideal ergonomic philosophy. However, further detailed study (laboratory and field study) needs to be done to uncover fully the parameters or factors that constrain the ergonomic comfortability in the motorcycle riding process. © 2011 Wiley Periodicals, Inc.

Muscles force and joints load simulation of bicycle riding using multibody models

A three dimensional multibody dynamic numerical model using LifeMOD and ADAMS is presented to simulate and analyze the load of wrists, shoulders, leg muscles, knees, and ankles of bicycle riding. Applications of ADAMS/LifeMOD are widely used, for example, rifle shot stress to the human body, golf swing, Tae Kwon Do side kick simulation, rowers paddle boat. Applications are even in the medical research including dynamic stability of human spine simulation, and thoracic and lumbar dynamic simulation. Vertical (height) and horizontal position of bicycle saddle are adjusted in the three dimensional multibody model to simulate muscles force for city bicycle riding and race bicycle riding. Besides, loads of shoulders, wrists, knees, and ankles are analyzed between postures of city bicycle riding and race bicycle riding. The objective of this research is to obtain a suitable posture either for city bicycle riding or race bicycle riding to prevent sports injuries. ADAMS/LifeMOD simulation of riding city bicycle and race bicycle with different riding postures is presented in this paper. Several main findings include: (1) If the bicycle saddle is too high, soleus force would be increased. (2) If the bicycle saddle is too low, biceps femoris and iliacus forces would be increased. (3) The influence on muscles force caused by a little adjustment of distance between saddle and handlebars may be ignored. (4) Posture of riding race bicycle bends upper body more and increases iliacus forces but decreases soleus force. (5) Because race bicycle riding posture bends upper body, the joints loads on lumbar, shoulders and elbows are greatly increased.

승마 평보와 속보시 기승자세의 운동학적 비교분석

The purpose of the study was to present the quantitative data utilizing in various teaching of horse riding by comparison·analysis of kinematic variables by phases & events of walking and trot used The JE-JU-horse. Participated subjects consisted of 5 horse riding experts and experiment method was based on 3D cinematography(Kwon3D Motion Analysis System). The variables was composed of temporal, linear and angular data. It was considered that ratio of elapsed time of supporting & swing phase during 1 stride was consisted of 59% & 41% and 49% & 51% in walking and trot and was proper portions. Trot continued more lager 2.46 cm range of movement in up-down direction with rising & sitting and significant difference in velocity of right-left & up-down direction and more increased in right-left sway velocity than walking. Trot continued more flexion in elbow, extension in shoulder, flexion in hip, extension in knee and more planter flexion in ankle than walking. Also trot continue more forward, while walking continued backward to vertical live through 1 stride Riding posture.

1A2-M05 生体信号処理と推論アルゴリズムによる自転車運動姿勢の最適化手法の提案

This study focuses on the importance of a riding posture of bicycle. Recently, the utilization of bicycle has been reviewed against latter social issues, such as global warming, destabilizing oil price, and diseases associated with adult lifestyle habits. A riding form of bicycle is basically determined with the mechanical settings of bicycle components, especially the saddle height has an significant influence on user's performance because muscular activities and joint mobilities are forcibly restricted. Conventional determination method for saddle height of bicycle is depending on the individual riding feelings, since there were no numerical evaluation method for the relationship between bicycle position and user's physical properties. Then we firstly define a new performance evaluation criterion based on leg electromyography during pedaling, and propose an optimization method of bicycle saddle height by using Fuzzy inference.