20 research outputs found
A Review on Automatic Visual Inspection for Railway Overhead Contact Line Systems
No full textInspections of overhead catenary systems include checks on the geometry of contact wire, the interaction between contact wire and pantograph, defects in components, worn components, and clearance are necessary to ensure the reliability, availability, maintainability, and safety of railways infrastructure and operation. An automatic visual inspection technology of overhead catenary systems can improve conventional inspection methods\u27 efficiency, cost-effectiveness, and precision. This paper provides an overview and contributions of the research made by scholars in this field, as well as the application and advancement of automated visual inspection technology for railway overhead catenary systems. The projection of the future research direction for automatic inspection in overhead catenary system inspection activities was also provided.Inspeksi sistem overhead catenary meliputi pemeriksaan pada geometri kawat kontak, interaksi antara kawat kontak dan pantograf, cacat pada komponen, komponen yang aus, dan jarak bebas sangat diperlukan untuk memastikan keandalan, ketersediaan, pemeliharaan keselamatan infrastruktur dan operasi kereta api. Teknologi inspeksi visual otomatis pada sistem overhead catenary dapat meningkatkan efisiensi, efektivitas biaya, dan presisi jika dibandingkan dengan metode inspeksi konvensional. Makalah ini memberikan gambaran umum dan kontribusi penelitian yang dilakukan oleh para ahli di bidang ini, serta aplikasi dan kemajuan teknologi inspeksi visual otomatis untuk sistem overhead catenary kereta api. Proyeksi arah penelitian di masa depan untuk sistem inspeksi otomatis dalam kegiatan inspeksi sistem catenary overhead juga akan dibahas
Markerless Optical Motion Capture System for Asymmetrical Swimming Stroke
No full textThis work presents the development of a markerless optical motion capture system of the front-crawl swimming stroke. The system only uses one underwater camera to record swimming motion in the sagittal plane. The participant in this experiment was a swimmer who is active in the university’s swimming club. The recorded images were then segmented to obtain silhouettes of the participant by a Gaussian Mixture Model. One of the swimming images was employed to generate a human body model that consists of 15 segments. The silhouette and model of the participant were subjected to an image matching process. The shape of the body segment was used as the feature in the image matching. The model was transformed to estimate the pose of the participant. The intraclass correlation coefficient between the results of the developed system and references were evaluated. In general, all body segments, except head and trunk, had a correlation coefficient higher than 0.95. Then, dynamics analysis by SWUM was conducted based on the joint angle acquired by the present work. The simulation implied that the developed system was suitable for daily training of athletes and coaches due to its simplicity and accuracy
Development of Image Processing & Thermal Camera for Railway Vehicle Bearing Inspection: A Review
No full textInspection of the train’s bearings is an important aspect of maintaining the performance and operational safety of the rail transportation system. Bearings act as components that support wheel rotation and transmit loads between the wheels and the axles. The poor condition of bearings can cause operational disruptions, decreased efficiency, and even failures that can endanger the safety of train passengers and personnel. In recent years, the use of thermal camera sensor technology in the inspection of railway bearings has grown rapidly. The thermal camera sensor enables accurate temperature detection and visualization of heat patterns on the bearing surface. Abnormal heating patterns can indicate a problem such as excess friction, wear, or overheating that needs action. In this review paper, the importance of checking bearings on trains, image processing, and object detection technologies in detecting damage, the use of thermal camera sensors in inspections, and the benefits that can be obtained by implementing this technology will be discussed in detail. This study is intended to provide a better understanding of bearing inspection on trains and its contribution to improving the safety and efficiency of the rail transportation system
Backpack Effects on Two-Dimensional Gait Spatiotemporal and Kinematic Parameters
No full textLoads could affect the body gait in various ways. Backpacks, sling bags, suitcases, and even trolleys could hugely affect human gait without us realizing it. The effects of these loads have been scientifically researched in biomechanics and sports science for the past few years. For instance, the comparison of walking with and without a backpack could easily reveal significant differences in body segments, which could be utilized for therapy and medicine development. The aim of this research is to determine the differences of the spatiotemporal kinematic parameters between a conventional human gait and a backpack-loaded gait. Some parameters to be highlighted are stride lengths, stride duration, joint angles, linear and angular segment positions, velocities, and accelerations. The method used for marker data acquisition is based on the 2-dimensional Direct Linear Transformation. The results demonstrate that the backpack increases stride lengths and reduces stride duration, contrast to the expected where backpacks would reduce stride lengths. It was observed that the angle between the bag and the body posterior affects the abdomen relative angle, which directly translates to stride lengths as well. During unloaded walking, increases in pelvic rotation contribute to increases in stride length with increasing walking speed. However, in loaded walking, the back angle is also a factor in determining kinematic parameters
Development of a 3D Gait Measurement Protocol for Amputees Walking on Treadmill
No full textWalking motion is actually a complex activity since it involves many body parts, especially the lower limb. Due to the needs for gait analysis in many medical applications, Biomechanics Research Team at ITB has developed an affordable optical motion analyzer to measure motions of subject walking over ground. However, the needs for multicycles gait data is better met by measuring subjects walking on treadmill. This paper discusses the modification of the developed motion analyzer to accommodate data acquisition of subject walking on treadmill, including those of transfemoral amputees. Seven markers, two 95 fps cameras, a dual-channel Camera Link Acquisition NI PCIe-1430 frame grabber, and a workstation are employed in the optical motion analyzer system. The speed displayed on the treadmill is evaluated. Additional equipment such as the modified hydraulic engine crane and the body harness are introduced to ensure the safety of amputees and avoid the risk of falling down while walking on the treadmill. The modified motion analyzer system is then used to obtain gait parameters of normal (37 males and 31 females) and three amputee subjects. The gait parameters of normal subjects in the treadmill walking shows that there is a decrease in the stride length and range of motion, and increase in the cadence due to walking adaptation. There are also phase shifting and increase in the range of motion for amputee subjects compared to the normal subjects which imply that there is an extra work done by the residual limb in doing walking movement and the amputee subjects try to balance their walking on the treadmill
Design optimization, manufacturing, and testing of affordable 3-axis load cell for reliable force plate component
No full textRedesign of a Biomechanical Energy Regeneration-based Robotic Ankle Prosthesis using Indonesian Gait Data
No full textIn this research, the robotic ankle design from Arizona State University (ASU) known as SPARKy was redesigned to accommodate the specific needs of Indonesian people. Most active prosthetic legs are designed based on gait parameters for people from Western countries, which may differ for people from other cultures that have a different anthropometry and economic background. Indonesians have smaller actuating power characteristics compared to people from Western cultures due to their smaller average weight and body height. Thus, the applied design strategy took advantage of a biomechanical energy regeneration scheme to reduce the actuator input power requirement and the relatively smaller mechanical power of the typical Indonesian ankle to create a potentially affordable robotic ankle with a smaller actuator that meets the technical specifications. The specifications of the powered prosthetic ankle were determined through the same methods used by SPARKy. Only one low-level control system, to actuate normal walking, was designed and tested on a fully assembled robotic ankle. The test results indicated a promising low-level control, where the robotic ankle can follow the predetermined trajectory required to actuate normal walking based on Indonesian gait data
