Papers by Keyword: Posture

Abstract: Work-related Musculoskeletal Disorders (WMSDs) have been seen as major health problems that have direct impacts on workers’ physical/psychosocial well beings, health, and productivity. Thus, the assessment of Musculoskeletal Disorders (MSDs) in sawmills will lead to a suitable platform for development and execution of proper ergonomic intervention programmes to achieve desirable workplaces. This research focused on determining the prevailing factors associated with MSDs and establishment of exposure’s level of sawmill workers to MSDs, based on risk and postural analyses using Quick Exposure Check (QEC), Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment Method (RULA); and physical strain assessment using relative Cardiovascular Load (% CVL), Cardiovascular Strain (% CVS) and Relative Heart Rate (%RHR) equations. Six hundred and sixty – three (663) male and thirty – three (33) female workers participated in the research survey and the participants were classified into two groups: machine operators’ classification (which included: Band-saw Operators (BOs), Circular-saw Operators (COs) and Planer Operators (POs)) and sawmill workers’ classification (which included: Machine Operators (MOs), Mill Workers (MWs), Dust Parkers (DPs); and Machine Maintenance Personnel (MMPs)). Ninety – six (96) workers each from each machine operators’ classification group (making 288 MOs), 240 MWs, 96 DPs, and 72 MMPs were considered for this study. Two cities were considered in each six Southwestern States of Nigeria, namely: Ekiti, Lagos, Ogun, Ondo, Osun, and Oyo States and a minimum of two sawmills were used in each city. The results of the postural analysis using QEC, REBA, and RULA show that an appreciable number of workers were working above the secured limit. Physical strain assessment results showed that not less than 60% of the workers were operating under high or very high-level discomfort and 61.8% of the workers were subjected to either heavy or very heavy work intensity.

Abstract: In automotive repair facilities worldwide, technicians are exposed to various ergonomic risk factors such as excessive exertions, awkward and static postures. The exposure of several ergonomic risk factors can lead to work related musculoskeletal complaints. This study was set out to examine working postures encountered by automotive service technicians in a small medium industry automotive workshop. A total of 240 observations (n=240) were made, and five types of working positions were identified, namely the “Underneath Vehicle” (vehicle on floor),“Side of Vehicle” (vehicle on floor), “Under the Hood”, “Side of Vehicle” (vehicle on lift), and “Underneath Vehicle” (vehicle on lift). Two positions, which were the “Underneath Vehicle” (vehicle on floor), and the “Side of Vehicle” (vehicle on floor) recorded 69 and 60 occurrences respectively. These two positions posed a significant ergonomic injury risk since the upper limbs, shoulders, spinal flexion combined with static holding were present in those two positions.

Abstract: In the study of excavator automation, the conventional contact-type sensors can be easily damaged because of the collision or vibration when measuring the posture of excavator’s manipulator. For this case, a novel vision-based approach for measuring the posture of excavator’s manipulator is proposed. In this approach, an industrial camera with an infrared filter is used to grab the perspective images of the manipulator under the irradiation of a LED infrared light source; and saddle point detection is adopted to detect the man-made targets which fixed on every arm of the manipulator. Then the selection algorithm based on the fixed geometric dimensioning between two targets is optimized to select the saddle point in targets, and the posture angle of the corresponding arm can be derived from the saddle point coordinates. Furthermore, the detection regions are tracked by anticipating the three group targets’ movement separately. Experiments show that with the infrared device, the vision-based posture measurement system of the excavator’s manipulator can better adapt to different illumination intensity conditions; and the optimization of target selection algorithm reduces the false detection rate from 4 times in every 30s to 1 time in every 30s; also, the average processing time for every manipulator movement frame is reduced from about 70 ms to 50ms by tracking the detection regions separately.

Abstract: A class of height double PID controller based on posture stability is designed in this paper aim at simplified dynamics model of missile pitch channel linearization and simplified model of missile height kinematics link. The implement process of using matlab software simulink toolbox is introduced in detail. Secondly, The transfer function calculating algorithm which solves nonlinear link in simulink using matlab language linmod function is proposed in this paper aim at nonlinear of height kinematics link. Finally, the bode diagram of whole system is obtained and the stability margin of system is analyzed by computer simulation.

Abstract: In basketball training, if the posture of basketball player is deviated, great impact will be brought to basketball training. Therefore, this paper presents a posture correction technology based on vision analysis. A lot of computer vision image are collected in basketball training, this images are enhanced to improve definition of image, with the high-quality images to identify wrong posture, and compare with standard posture to achieve posture correction in basketball training. Experimental results show that the proposed algorithm for posture correction in basketball training can improve the accuracy of correction, so as to meet the actual needs of basketball training.

Abstract: In this paper, three wire structure of the airflow level posture sensor is described. Using ANSYS-FLOTRAN CFD program, the temperature field and the stream field in sensing element of three wire structure and two wire structure under the effect of the different tilt state, has been obtained by a series of procedure, such as model building, meshing, loads applying and equation solving. The results are as follow: In tilt status, the airflow rate difference of three wire structure is nearly five times bigger than two wire structure in the two heat sources. Three wire structure makes heating wire separated from detection wire, solves the contradiction between operating current and output sensitivity, and decrease operating current. The test results show: The compare between three wire structure of the airflow level posture sensor and two wire structure of the airflow level posture sensor is that the sensitivity increases from 10 mV /° to 18mV/°,response time decreases from 100mS to 40mS,operating current decreases from 80mA to 40mA, so three wire structure is better than two wire structure.

Abstract: This paper presents a study in batik industry with the objective of determining any musculoskeletal disorders (MSDs) among canting batik workers in Kuala Terengganu. The MSDs symptoms were identified through questionnaires modified from a Standardized Nordic Questionnaire (SNQ) and from observational techniques by using a postural analysis tool, Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA). The results of questionnaires revealed that MSDs occurred at a high rate which the highest rates of MSDs prevalence were reported in shoulders (64.5%). By assessing postural using the REBA software, the score 4 placed it in medium risk level. However, there are other factors contribute to the existence of MSD such as prolong standing, repetitive movement and poor workstation design. These parameters are not taken into account in the RULA and REBA analysis. Thus, designing an ergonomic workstation may prevent awkward postures to provide a maximum comfort to the batik workers and consequently enhance the productivity. Keywords : batik, posture, musculoskeletal disorders, RULA,REBA

Abstract: Musculoskeletal disorder (WMSDs) is the common health problems for the industrial workers. This health problem can contribute to long term effect on the production performance. The objective of this study is to analyze the posture of industrial worker in packaging industry using the RULA assessment in CATIA P3 V5R14 software. The working posture was reconstructed and developed in the CATIA P3 V5R14 software and then RULA assessment was conducted. From the RULA analysis, several awkward postures were detected to be high in risk factors. The postures in risk are postures 1,2 and 5 which mainly involve lifting heavy product and excessive bending. As a conclusion the RULA assessment was able to detect the problematic postures and further improvement can be conducted to avoid discomfort or further health complication.

Abstract: In this paper we present some theoretical and practical considerations concerning the development procedures of some correlative investigation techniques (CIT) applied to human performances analysis expressed in specific evolution conditions of some postural malfunctions. These integrated correlative techniques may define and control by feed-back reactions the behavior of some bio-systems or even of some automated and robotized systems.

Abstract: Traumas of locomotion system, even recovered at a great extent may change subjects’ posture and stability along time by determining an emphasis of balance or forces developed at the foot-ground contact level. In this paper we present the analysis of a subject’s case study, after a trauma in the heel area, which recovered by surgery and physical and kinetic therapy, but whose normal and/or added steps gait was changed due to the prolonged recovery time. The analysis method is based upon the information gathered from the Footscan plate sensors at the contact moment between the locomotion system (sole) and the ground. In the first part of the paper, the fundamental aspect related to the measuring of contact pressure between the human body and the ground in dynamic regime are presented, also the influence of the trunk and head posture upon this type of locomotion action. In the second part, the experimental system and the experimental development are presented, while in the final part we show the results and conclusions of this experimental research on specific case studies.