M. Tavakoli, M.R. Zakerzadeh, G.R. Vossoughi and S. Bagheri
Aims to describe design, prototyping and characteristics of a pole climbing/manipulating robot with ability of passing bends and branches of the pole.
Abstract
Purpose
Aims to describe design, prototyping and characteristics of a pole climbing/manipulating robot with ability of passing bends and branches of the pole.
Design/methodology/approach
Introducing a hybrid (parallel/serial) four degree of freedom (DOF) mechanism as the main part of the robot and also introduces a unique gripper design for pole climbing robots.
Findings
Finds that a robot, with the ability of climbing and manipulating on poles with bends and branches, needs at least 4 DOFs. Also an electrical cylinder is a good option for climbing robots and has some advantages over pneumatic or hydraulic cylinders.
Research limitations/implications
The robot is semi‐industrial size. Design and manufacturing of an industrial size robot are a good suggestion for future works.
Practical implications
With some changes on the gripper module and the last tool module, the robot is able to do some service works like pipe testing, pipe/pole cleaning, light bulb changing in highways etc.
Originality/value
Design and manufacturing of a pole‐climbing and manipulating robot with minimum DOFs for construction and service works.
Details
Keywords
Field robots can surmount or avoid some obstacles when operating on rough ground. However, cable-climbing robots can only surmount obstacles because their moving path is…
Abstract
Purpose
Field robots can surmount or avoid some obstacles when operating on rough ground. However, cable-climbing robots can only surmount obstacles because their moving path is completely restricted along the cables. This paper aims to analyse the dynamic obstacle-surmounting models for the driving and driven wheels of the climbing mechanism, and design a mechanical structure for a bilateral-wheeled cable-climbing robot to improve the obstacle crossing capability.
Design/methodology/approach
A mechanical structure of the bilateral-wheeled cable-climbing robot is designed in this paper. Then, the kinematic and dynamic obstacle-surmounting of the driven and driving wheels are investigated through static-dynamic analysis and Lagrangian mechanical analysis, respectively. The climbing and obstacle-surmounting experiments are carried out to improve the obstacle crossing capability. The required motion curve, speed and driving moment of the robot during obstacle-surmounting are generated from the experiments results.
Findings
The presented method offers a solution for dynamic obstacle-surmounting analysis of a bilateral-wheeled cable-climbing robot. The simulation, laboratory testing and field experimental results prove that the climbing capability of the robot is near-constant on cables with diameters between 60 and 205 mm.
Originality/value
The dynamic analysis method presented in this paper is found to be applicable to rod structures with large obstacles and improved the stability of the robot at high altitude. Simulations and experiments are also conducted for performance evaluation.
Details
Keywords
Yanzhang Yao, Wei Wang, Yue Qiao, Zhihang He, Fusheng Liu, Xuelong Li, Xinxin Liu, Dehua Zou and Tong Zhang
The purpose of this paper is to describe the design and development of a novel series-parallel robot, which aims to climb on the transmission tower.
Abstract
Purpose
The purpose of this paper is to describe the design and development of a novel series-parallel robot, which aims to climb on the transmission tower.
Design methodology approach
This study introduces a hybrid robot, which consists of adsorption and two 3-degree of freedom (DOF) translation parallel legs connected by a body linkage. The DOF of the legs ensures that the robot can move on the climbing plane, also contribute to a compact design of the robot. An electromagnet is used to adsorb onto the transmission tower, simplifying the overall structure. Based on the robot design, this paper further defines its climbing gait and adopt the 6th B-spline curves for climbing trajectory planning under different working environments.
Findings
The developed prototype that implements the design of the robot, which was used in simulation and experiments, showing that the robot is capable of climbing in the test environments with the planned climbing gait.
Originality value
The hybrid robot is able to climb under varying degrees of inclinations and cross the obstacles, and the magnetic attraction can ensure stable climbing.
Details
Keywords
Hadi Minbashian, Hojatollah Adibi and Mehdi Dehghan
This paper aims to propose an adaptive method for the numerical solution of the shallow water equations (SWEs). The authors provide an arbitrary high-order method using high-order…
Abstract
Purpose
This paper aims to propose an adaptive method for the numerical solution of the shallow water equations (SWEs). The authors provide an arbitrary high-order method using high-order spline wavelets. Furthermore, they use a non-linear shock capturing (SC) diffusion which removes the necessity of post-processing.
Design/methodology/approach
The authors use a space-time weak formulation of SWEs which exploits continuous Galerkin (cG) in space and discontinuous Galerkin (dG) in time allowing time stepping, also known as cGdG. Such formulations along with SC term have recently been proved to ensure the stability of fully discrete schemes without scarifying the accuracy. However, the resulting scheme is expensive in terms of number of degrees of freedom (DoFs). By using natural adaptivity of wavelet expansions, the authors devise an adaptive algorithm to reduce the number of DoFs.
Findings
The proposed algorithm uses DoFs in a dynamic way to capture the shocks in all time steps while keeping the representation of approximate solution sparse. The performance of the proposed scheme is shown through some numerical examples.
Originality/value
An incorporation of wavelets for adaptivity in space-time weak formulations applied for SWEs is proposed.
Details
Keywords
Jun Luo, Shaorong Xie, Zhenbang Gong and Tiansheng Lu
In order to replace the conventional human maintenance of cable‐stayed bridges, a robot is designed and constructed for tasks such as cleaning, painting and rust‐detecting.
Abstract
Purpose
In order to replace the conventional human maintenance of cable‐stayed bridges, a robot is designed and constructed for tasks such as cleaning, painting and rust‐detecting.
Design/methodology/approach
Adopting a modular approach, two kinds of climbing mechanisms, plus a painting mechanism and a rust‐detecting method are designed.
Findings
A robot that can climb and maintain the cables of cable‐stayed bridges has been designed and constructed. It has been proved by experiment that the robot can overcome many disadvantages of conventional human bridge‐maintenance, and drastically improve efficiency, cost, and safety.
Research limitations/implications
The robot is of industrial size, but a new mechanism requiring less installing time will be designed for the future.
Practical implications
The robot has been applied to cables of the Nanpu Bridge and Xupu Bridge in Shanghai. More than 80 cable‐stayed bridges and six suspension bridges have been built or are being constructed across large rivers in China alone. This gives an enormous potential market.
Originality/value
The cable maintenance robot developed in this paper is the world's first special robot for the cables of cable‐stayed bridges.
Details
Keywords
This study aims to investigate a critical review on the applications of fluid-structure interaction (FSI) in porous media.
Abstract
Purpose
This study aims to investigate a critical review on the applications of fluid-structure interaction (FSI) in porous media.
Design/methodology/approach
Transport phenomena in porous media are of continuing interest by many researchers in the literature because of its significant applications in engineering and biomedical sectors. Such applications include thermal management of high heat flux electronic devices, heat exchangers, thermal insulation in buildings, oil recovery, transport in biological tissues and tissue engineering. FSI is becoming an important tool in the design process to fully understand the interaction between fluids and structures.
Findings
This study is structured in three sections: the first part summarizes some important studies on the applications of porous medium and FSI in various engineering and biomedical applications. The second part focuses on the applications of FSI in porous media as related to hyperthermia. The third part of this review is allocated to the applications of FSI of convection flow and heat transfer in engineering systems filled with porous medium.
Research limitations/implications
To the best knowledge of the present authors, FSI analysis of turbulent flow in porous medium never been studied, and therefore, more attention should be given to this area in any future studies. Moreover, more studies should also be conducted on mixed convective flow and heat transfer in systems using porous medium and FSI.
Practical implications
The wall of the blood vessel is considered as a flexible multilayer porous medium, and therefore, rigid wall analysis is not accurate, and therefore, FSI should be implemented for accurate predictions of flow and hemodynamic stresses.
Social implications
The use of porous media theory in biomedical applications received a great attention by many investigators in the literature (Khanafer and Vafai, 2006a; Al-Amiri et al., 2014; Lasiello et al., 2016a, Lasiello et al., 2016b; Lasiello et al., 2015; Chung and Vafai, 2013; Mahjoob and Vafai, 2009; Yang and Vafai, 2008; Yang and Vafai, 2006; Ai and Vafai, 2006). A comprehensive review was conducted by Khanafer and Vafai (2006b) summarizing various studies associated with magnetic field imaging and drug delivery. The authors illustrated that the tortuosity and porosity had a profound effect on the diffusion process within the brain. AlAmiri et al. (2014) conducted a numerical study to investigate the effect of turbulent pulsatile flow and heating technique on the thermal distribution within the arterial wall. The results of that investigation illustrated that local heat flux variation along the bottom layer of the tumor was greater for the low-velocity condition. Yang and Vafai (2006) presented a comprehensive four-layer model to study low-density lipoprotein transport in the arterial wall coupled with a lumen (Figure 1). All the four layers (endothelium, intima, internal elastic lamina and media) were modeled as a homogenous porous medium.
Originality/value
Future studies on the applications of FSI in porous media are recommended in this review.
Details
Keywords
Xiaolong Lu, Shiping Zhao, Deping Yu and Xiaoyu Liu
The purpose of this paper is to describe the design and development of “Pylon-Climber”, a pole climbing robot (PCR) for climbing along the corner columns of electricity pylon and…
Abstract
Purpose
The purpose of this paper is to describe the design and development of “Pylon-Climber”, a pole climbing robot (PCR) for climbing along the corner columns of electricity pylon and assisting the electricians to complete maintenance tasks.
Design/methodology/approach
Introduces a PCR that is composed of a simple climbing mechanism and two novel grippers. The gripper consists of two angle-fixed V-blocks, and the size of V-block is variable. The clamping method of the angle bar meets the requirement of the force closure theorem. The whole design adopts symmetrical design ideas.
Findings
The developed prototype proved possibility of application of PCRs for inspection and maintenance of pylon. The novel gripper can provide enough adhesion force for climbing robot.
Practical implications
The robot is successfully tested on a test tower composed of different specification steel angles, oblique ledges and overlapping steel struts.
Originality/value
Design and development of a novel climbing assistive robot for pylon maintenance. The robot is able to climb along the column of electricity pylon and pass all obstacles. The gripper can reliably grasp the angle bar with different specification and overlapping steel struts from multiple directions.
Details
Keywords
Mahmoud Tavakoli, Lino Marques and Aníbal T. de Almeida
The purpose of this paper is to describe design and development of a pole climbing robot (PCR) for inspection of industrial size pipelines. Nowadays, non‐destructive testing (NDT…
Abstract
Purpose
The purpose of this paper is to describe design and development of a pole climbing robot (PCR) for inspection of industrial size pipelines. Nowadays, non‐destructive testing (NDT) methods are performed by dextrous technicians across high‐level pipes, frequently carrying dangerous chemicals. This paper reports development of a PCR that can perform in situ manipulation for NDT tests.
Design/methodology/approach
Introduces a PCR including a novel four‐degrees of freedom climbing serial mechanism with the nearly optimal workspace and weight, unique V‐shaped grippers and a fast rotational mechanism around the pole axis. Simplicity, safety, minimum weight, and manipulability were concerned in the design process.
Findings
The developed prototype proved possibility of application of PCRs for NDT inspection on elevated structures. Design and development of PCRs which are able to pass bends and T‐junctions faces much more difficulties than those which should climb from a straight pole.
Practical implications
The robot is successfully tested on an industrial size structure (exterior diameter of 219 mm) with bends and T‐junctions.
Originality/value
Design and development of a novel pole climbing and manipulating robot for inspection of industrial size pipelines. The robot is able to pass bends and T‐junctions. The V‐shaped grippers offer many advantages including safety and tolerance to power failure. After grasping the structure, in case of power failure in any of the grippers' motors, the robot does not slip on the structure. The Z‐axis rotational mechanism provides fast navigation around the pole which is not possible with the traditional serial articulated arms.
Details
Keywords
H. Benyaghla, M. Meksaouin and L. Belabed
Two theoretical models very simple in calculation of active earth pressure of prism of three-dimensional rupture mobilised behind pile or screen in translation, were proposed…
Abstract
Two theoretical models very simple in calculation of active earth pressure of prism of three-dimensional rupture mobilised behind pile or screen in translation, were proposed. Improvements were done in order to pass from one to another, by the introduction of frustum of cone, which permits to obtain forms of prism of rupture more near to the reality. Basing on Kinematics Theorem of Drucker and Prager of limit analysis theory, there models give, in this way, two boundary-stones or superiors limits of this active earth pressure according to real value of this last. This is effectively well verified on experimental trials realized.
Details
Keywords
Xiaolong Lu, Shiping Zhao, Xiaoyu Liu and Yishu Wang
The purpose of this paper is to describe the design and development of “Pylon-Climber II”, a 5-DOF biped climbing robot (degree of freedom – DOF) for moving on the external…
Abstract
Purpose
The purpose of this paper is to describe the design and development of “Pylon-Climber II”, a 5-DOF biped climbing robot (degree of freedom – DOF) for moving on the external surface of a tower and assisting the electricians to complete some maintenance tasks.
Design/methodology/approach
The paper introduces a pole-climbing robot, which consists of a 5-DOF mechanical arm and two novel grippers. The gripper is composed of a two-finger clamping module and a retractable L-shaped hook module. The robot is symmetrical in structure, and the rotary joint for connecting two arms is driven by a linear drive mechanism.
Findings
The developed prototype proved a new approach for the inspection and maintenance of the electricity pylon. The gripper can reliably grasp the angle bars with different specifications by using combined movement of the two-finger clamping module and the retractable L-shaped hook module and provide sufficient adhesion force for the Pylon-Climber II.
Practical implications
The clamping experiments of the gripper and the climbing experiments of the robot were carried out on a test tower composed of some angle bars with different specification.
Originality/value
This paper includes the design and development of a 5-DOF biped climbing robot for electricity pylon maintenance. The climbing robot can move on the external surface of the electric power tower through grasping the angle bar alternatively. The gripper that is composed of a two-finger gripping module and a retractable L-shaped hook module is very compact and can provide reliable adhesion force for the climbing robot.