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1 – 10 of 44Jiaoli Piao, Yehyoun Kim, Ru Han, Darinka Popov and Sumin Koo
An increasing aging population and an increasing number of people suffering from musculoskeletal disorders have increased the demand for wearable robots. Comfortable, wearable…
Abstract
Purpose
An increasing aging population and an increasing number of people suffering from musculoskeletal disorders have increased the demand for wearable robots. Comfortable, wearable robots that can be worn like clothing are currently being investigated. However, the embedded components may be displaced owing to the flexibility of the fabrics, which can lower the sensing accuracy and limit natural body movements. This study aims to develop clothing-type wearable platforms to minimize the displacement of embedded components such as sensors and actuators while maintaining comfort.
Design/methodology/approach
Four designs were developed using materials with different seam lines, that can serve as anchoring details, and flatlock stitches considering body movements and musculoskeletal structures. The wear evaluation experiment was filmed using a speed camera and analyzed using the TimeViewer software and SPSS 26.0. Based on these results, four clothing-type wearable platform designs were developed.
Findings
The variation in the location of a point in the armhole among the designs was marginal. Participants were satisfied with the functionality, practicality, wearability, efficiency and ease of use of the developed designs. A final clothing-type wearable platform was developed by applying a design with the least change in location, a suitable design for each area and wear comfort.
Originality/value
The results of this study contribute to the development of wearable robots by establishing clothing design data to minimize changes in sensor and actuator movements.
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Akinwale Okunola, Abiola Abosede Akanmu and Anthony Olukayode Yusuf
Low back disorders are more predominant among construction trade workers than their counterparts in other industry sectors. Floor layers are among the top artisans that are…
Abstract
Purpose
Low back disorders are more predominant among construction trade workers than their counterparts in other industry sectors. Floor layers are among the top artisans that are severely affected by low back disorders. Exoskeletons are increasingly being perceived as ergonomic solutions. This study aims to compare the efficacy of passive and active back-support exoskeletons by measuring range of motion, perceived discomfort, usability, perceived rate of exertion and cognitive load during a simulated flooring task experiment.
Design/methodology/approach
In this study eight participants were engaged in a repetitive timber flooring task performed with passive and active back-support exoskeletons. Subjective and objective data were collected to assess the risks associated with using both exoskeletons. Descriptive statistics were used for analysis. Scheirer-Ray-Hare test and Wilcoxon signed-rank test were adopted to compare the exoskeleton conditions.
Findings
The results show no significant differences in the range of motion (except for a lifting cycle), perceived level of discomfort and perceived level of exertion between the two exoskeletons. Significant difference in overall cognitive load was observed. The usability results show that the active back-support exoskeleton made task execution easier with less restriction on movement.
Research limitations/implications
The flooring task is simulated in a laboratory environment with only eight male participants.
Originality/value
This study contributes to the scarce body of knowledge on the usage comparison of passive and active exoskeletons for construction work.
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Søren Munch Lindhard, Astrid Heidemann Lassen, Yang Cheng, Matteo Musso, Geng Wang and Shaoping Bai
Exoskeletons are moving into industries with the potential to reduce muscle strains and prevent occupational injuries. Although exoskeletons have been designed and tested in…
Abstract
Purpose
Exoskeletons are moving into industries with the potential to reduce muscle strains and prevent occupational injuries. Although exoskeletons have been designed and tested in laboratory settings, rare empirical studies of their application in construction have been reported. Therefore, the purpose of this study is on in a real-life setting testing the applicability of adopting exoskeletons in the construction industry.
Design/methodology/approach
A feasibility study of exoskeletons in construction is conducted by testing a passive exoskeleton, designed for shoulder support. Five bricklayers tested in a two-month period the exoskeleton, each wearing it for a three-day period while carrying out normal work activities. Test data in terms of interviews were collected and analyzed using qualitative content analysis.
Findings
The application of exoskeletons in construction revealed several limitations, where the two primary ones are the exoskeleton is not designed while considering the tasks of a bricklayer causing several challenges and the exoskeleton only supports a single upward motion while limiting other movements and even counteracted when a downward movement was necessary.
Originality/value
The identified challenges could easily have been revealed by coupling the design and testing of exoskeletons to actual application. Thus, the design approach needs to be reversed. Instead of designing an exoskeleton to support a specific body part or motion and then identifying where it is applicable, it should target specific industries and focus on the actual work and movements and the necessary support. As part of the change, the design metrics should be reevaluated to reflect the work to support.
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Ruoxing Wang, Shoukun Wang, Junfeng Xue, Zhihua Chen and Jinge Si
This paper aims to investigate an autonomous obstacle-surmounting method based on a hybrid gait for the problem of crossing low-height obstacles autonomously by a six wheel-legged…
Abstract
Purpose
This paper aims to investigate an autonomous obstacle-surmounting method based on a hybrid gait for the problem of crossing low-height obstacles autonomously by a six wheel-legged robot. The autonomy of obstacle-surmounting is reflected in obstacle recognition based on multi-frame point cloud fusion.
Design/methodology/approach
In this paper, first, for the problem that the lidar on the robot cannot scan the point cloud of low-height obstacles, the lidar is driven to rotate by a 2D turntable to obtain the point cloud of low-height obstacles under the robot. Tightly-coupled Lidar Inertial Odometry via Smoothing and Mapping algorithm, fast ground segmentation algorithm and Euclidean clustering algorithm are used to recognize the point cloud of low-height obstacles and obtain low-height obstacle in-formation. Then, combined with the structural characteristics of the robot, the obstacle-surmounting action planning is carried out for two types of obstacle scenes. A segmented approach is used for action planning. Gait units are designed to describe each segment of the action. A gait matrix is used to describe the overall action. The paper also analyzes the stability and surmounting capability of the robot’s key pose and determines the robot’s surmounting capability and the value scheme of the surmounting control variables.
Findings
The experimental verification is carried out on the robot laboratory platform (BIT-6NAZA). The obstacle recognition method can accurately detect low-height obstacles. The robot can maintain a smooth posture to cross low-height obstacles, which verifies the feasibility of the adaptive obstacle-surmounting method.
Originality/value
The study can provide the theory and engineering foundation for the environmental perception of the unmanned platform. It provides environmental information to support follow-up work, for example, on the planning of obstacles and obstacles.
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Priyaranjan Biswal and Prases Kumar Mohanty
Legged walking robots have numerous advantages over the wheel or tracked robots due to their strong operational ability and exposure to the complex environment. This paper aims to…
Abstract
Purpose
Legged walking robots have numerous advantages over the wheel or tracked robots due to their strong operational ability and exposure to the complex environment. This paper aims to present details about the mechanical formation and a new conceptual elliptical trajectory generation discussed throughout the paper of the quadruped robot.
Design/methodology/approach
Initially, a realistic CAD model of the four-legged robot is developed in Solidwork-2019. The proposed model’s forward and inverse kinematics equations are deduced using Denavit–Hartenberg parameters. Based on geometry and kinematics, manipulability and obstacle avoidance are investigated. A method of galloping trajectory is proposed for aiming the increase of upright direction impulse, which is produced by ground reaction force at each step frequency. Furthermore, the locomotion equation of the ellipse trajectory is derived by setting transition angle polynomial of free-fall phase, stance phase and swing phase and the constraints.
Findings
Finally, a successive simulation on a 2D sagittal plane is performed to check and verify the usefulness of the proposed trajectory. Before the development of the full quadruped, a single prototype leg is generated for experimental verification of the dynamic simulations.
Originality/value
The proposed trajectory is novel in that it uses force tracking control, which is intended to improve the quadruped robot’s robustness and stability.
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Hang Guo, Xin Chen, Min Yu, Marcin Uradziński and Liang Cheng
In this study, an indoor sensor information fusion positioning system of the quadrotor unmanned aerial vehicle (UAV) was investigated to solve the problem of unstable indoor…
Abstract
Purpose
In this study, an indoor sensor information fusion positioning system of the quadrotor unmanned aerial vehicle (UAV) was investigated to solve the problem of unstable indoor flight positioning.
Design/methodology/approach
The presented system was built on Light Detection and Ranging (LiDAR), Inertial Measurement Unit (IMU) and LiDAR-Lite devices. Based on this, one can obtain the aircraft's current attitude and the position vector relative to the target and control the attitudes and positions of the UAV to reach the specified target positions. While building a UAV positioning model relative to the target for indoor positioning scenarios under limited Global Navigation Satellite Systems (GNSS), the system detects the environment through the NVIDIA Jetson TX2 (Transmit Data) peripheral sensor, obtains the current attitude and the position vector of the UAV, packs the data in the format and delivers it to the flight controller. Then the flight controller controls the UAV by calculating the posture to reach the specified target position.
Findings
The authors used two systems in the experiment. The first is the proposed UAV, and the other is the Vicon system, our reference system for comparison purposes. Vicon positioning error can be considered lower than 2 mm from low to high-speed experiments. After comparison, experimental results demonstrated that the system could fully meet the requirements (less than 50 mm) in real-time positioning of the indoor quadrotor UAV flight. It verifies the accuracy and robustness of the proposed method compared with that of Vicon and achieves the aim of a stable indoor flight preliminarily.
Originality/value
Vicon positioning error can be considered lower than 2 mm from low to high-speed experiments. After comparison, experimental results demonstrated that the system could fully meet the requirements (less than 50 mm) in real-time positioning of the indoor quadrotor UAV flight. It verifies the accuracy and robustness of the proposed method compared with that of Vicon and achieves the aim of a stable indoor flight preliminarily.
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Huang Taiming, JingMao Ma, Li Zhang, Pan Hao, MingChen Feng, Wei Zeng and Changjie Ou
The purpose of this study is investigate the transient aerodynamic characteristics of high-speed vehicle with body roll motion under crosswind condition to improve aerodynamic…
Abstract
Purpose
The purpose of this study is investigate the transient aerodynamic characteristics of high-speed vehicle with body roll motion under crosswind condition to improve aerodynamic stability.
Design/methodology/approach
An overset mesh was used to simulate the rolling motion of the vehicle body. A wind tunnel experiment was conducted to validate the numerical method.
Findings
The results revealed that the vehicle’s aerodynamic characteristics changed periodically with the body’s periodic motion. In the absence of crosswind, the pressure distribution on the left and right sides of the vehicle body was symmetrical, and the speed streamline flowed to the rear of the vehicle in an orderly manner. The maximum aerodynamic lift observed in the transient simulation was −0.089, which is approximately 0.70 times that of the quasi-static simulation experiment. In addition, the maximum aerodynamic side force observed in the transient simulation was 0.654, which is approximately 1.25 times that of the quasi-static simulation experiment.
Originality/value
The aerodynamic load varies periodically with the vehicle body’s cyclic motion. However, the extreme values of the aerodynamic load do not occur when the vehicle body is at its highest or lowest position. This phenomenon is primarily attributed to the mutual interference of airflow viscosity and the hysteresis effect in the flow field, leading to the formation of a substantial vortex near the wheel. Consequently, the aerodynamic coefficient at each horizontal position becomes inconsistent during the periodic rolling of the vehicle body.
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Abhilash C.R., Sriraksha Murali, M. Abdul Haq, Tanay N. Bysani and N.S. Narahari
In certain industrial operations, workers are required to stand for a prolonged duration. This leads to muscular fatigue in the legs, posing a threat to the productivity and…
Abstract
Purpose
In certain industrial operations, workers are required to stand for a prolonged duration. This leads to muscular fatigue in the legs, posing a threat to the productivity and well-being of the workers. This paper aims to address this problem of women in the clothing industry with an exoskeleton designed for lower extremities and improve productivity.
Design/methodology/approach
Ulrich’s product design approach has been followed with suitable modifications. The methodology involves a study to justify the need for this product and terminating at the physical and virtual evaluations of the product. Required anthropometric parameters are considered along the design process.
Findings
The exoskeleton discussed in this paper is an innovative product made of Aluminium 6061 alloy. During the simulation phase of the product, total von-mises stresses to a part bearing 1 leg were 31.5 MPa, 94.7 MPa and 284 MPa for aluminium, SS308 and springs, respectively. These values are below the yield limit by a great margin. Based on a user survey of this product, 72% of the targeted customers were interested in buying. Also, comparing electromyography (EMG) mean value of the voltage between workers’ leg with and without exoskeleton revealed that there was an improvement in the voltage by 2.5% when exoskeleton was used.
Originality/value
This paper emphasizes, for the first time – the necessity of an exoskeleton indigenized for the Indian population and the process of realizing it by designing an exoskeleton.
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Isik Ates Kiral and Sevilay Demirkesen
This study aims to observe the impact of peripheral vision on construction safety. The study further intends to create awareness of eye diseases in construction safety, an…
Abstract
Purpose
This study aims to observe the impact of peripheral vision on construction safety. The study further intends to create awareness of eye diseases in construction safety, an important root cause for most construction-related hazards and accidents.
Design/methodology/approach
This study focuses on the impact of peripheral vision in terms of construction site safety. Experiments were conducted with construction employees with different qualifications, ages, expertise and previous safety training experience. The experiments were conducted with an experiment set consisting of a tangent screen to measure the peripheral angle of the participants. The study measured peripheral vision, which helped determine the vision field accordingly. In this context, a total of 32 participants were investigated in terms of their peripheral visual angle and the field of vision. The data collected were analyzed in terms of several statistical tests such as One-Sample t-test, multivariate ANOVA and multiple linear regression.
Findings
The results of the study indicated that there are significant differences in peripheral vision in terms of age of participants, work qualification, work experience, area of expertise and previous safety training experience. The study further revealed that most of the participants failed to satisfy both OSHA requirements about peripheral vision, and normal limits defined in the previous literature. The study further implies that participants, who reported previous sight problems or eye diseases are more vulnerable to construction site accidents.
Originality/value
Construction site safety remains a major concern for most construction companies despite the latest developments in technology. Several companies are struggling with poor safety performance, occupational injuries and illnesses, and work-related accidents resulting in fatalities. However, the root causes behind several construction accidents are still vague due to different dynamics in the construction industry. Among these root causes, poor sight, vision and or eye diseases constitute an important part. Hence, the study provides empirical evidence with the workers checked for eye health to help policymakers and industry practitioners in terms of developing awareness for eye-related injuries and accidents and review their safety programs accordingly.
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Mohamed Tahir Shoani, Mohamed Najib Ribuan and Ahmad 'Athif Mohd Faudzi
The current methods for inspecting tall or deep structures such as towers, chimneys, silos, and wells suffer from certain constraints. Manual and assisted inspection methods…
Abstract
Purpose
The current methods for inspecting tall or deep structures such as towers, chimneys, silos, and wells suffer from certain constraints. Manual and assisted inspection methods including humans, drones, wall climbing robots, and others are either costly, have a limited operation time, or affected by field conditions, such as temperature and radiation. This study aims to overcome the presented challenges through a teleoperated soft continuum manipulator capable of inspecting tall or deep structures with high resolution, an unlimited operation time and the ability to use different arms of the manipulator for different environments and structure sizes.
Design/methodology/approach
The teleoperated manipulator uses one rotary and two tendon actuators to reach and inspect the interior of a tall (or deep) structure. A sliding part along the manipulator’s body (arm constrainer and tendon router) induces a variable-length bending segment, allowing an inspection camera to be placed at different distances from the desired location.
Findings
The experiments confirmed the manipulator’s ability to inspect different locations in the structure’s interior. The manipulator also demonstrated a submillimeter motion resolution vertically and a 2.5 mm per step horizontally. The inspection time of the full structure was 48.53 min in the step-by-step mode and was calculated to be 4.23 min in the continuous mode.
Originality/value
The presented manipulator offers several design novelties: the arm’s thin-wide cross-section, the variable-length bending segment in a fixed-length body, the external rolling tendon routing and the ability to easily replace the arm with another of different material or dimensions to suite different structures and environments.
Details