Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

Analysis on steering characteristics of crawler pipeline robot

In order to improve the elbow passing performance and different diameter adaptability of pipeline robot,a supported crawler pipeline robot is designed,which adopts screw nut mechanism and hinge four-bar mechanism to adapt to the complex environment such as variable diameter pipeline and elbow.The steering characteristics passing through the elbow are studied,the kinematic of pipeline robot bending steering is established,the geometric constraint(GC)and steering constraint(SC)in the elbow are analyzed,and the steering experiment is conducted.The results show that the robot can pass through the elbow by the SC model.The SC model can reduce the motor current and energy consumption when the robot passes through the elbow.

Predictive Fuzzy Control of Pipeline Robot

A perdictive fuzzy control algorithm is proposed in order to solve the problems in engineering applications of pipeline robots as position information and uncertain operating conditions. Simulation results show that this algorithm improves the adaptability of the robots in the positioning process.

FMECA and FTA Methods of Reliability Analysis for Oil and Gas Pipeline Robot

In this paper,FMECA and FTA methods are presented for oil and gas Pipeline Robot in order to improve the reliability.Take a crawler pipeline cleaning robot as the research object.According to the robot′s variable working environment,high failure rate and short service life,in order to reduce the probability of its failure,and to extend its use time limit under the premise of being able to adapt to the complex working environment,and reduce maintenance cost of failure.To realize this purpose,FMECA analysis is fristly proposed,by which obtain the failure modes,causes and effects of each component mechanism,and identify the component mechanism with high risk and failure rate.Secondly,FTA is developed to establish the fault tree model of Cleaning and diameter changing mechanism,retain the underlying fault and the cause of its failure.Simulation results are carried out to illustrate the effectiveness of this proposed method and improvement measures to improve the reliability of the robot.

Traveling property of wheel-type pipeline robot with different configurations

In order to improve the travelling ability of the wheel-type pipeline robot in elbow section of pipeline, the model of drive ratios is proposed aiming at the pipeline robots with different configurations. Through the movement analysis of the robot with different configurations in elbow section, the pose model of the robot is established, and the coordinates of the wheel centers and the contact points can be got through the calculation of the pose model. Based on the pose model established, the corresponding drive ratios are obtained combining with the relations of the velocities of wheel centers and rotative velocities of wheels under the movement condition with no interference. The virtual simulations and prototype experiments are carried out, and the drive ratios accuracy of the model when the robot moved in elbow without interference is validated.

A Pipeline Inspection Micro Robot Based on Screw Motion Wheels

The micro robot based on screw motion wheels, which features high payload/mass ratio, fast and continuous motion, adaptation to pipe diameter or roundness variations, is suitable for locomotion and inspection inside small diameter pipelines. The robot inspection system, Tubot I, developed at Shanghai University is composed of locomotion mechanism with an inner motor, a micro CCD camera and a monitor outside the pipeline. In the paper, the kinematics and statics analyses are presented for the screw locomotion system of Tubot I. The moving characteristics are obtained from experiments on the robot prototype.

Design of a Submarine Pipeline Inspection Robot System Based on CT Technology

With the rapid development of submarine oil and gas,the security issues of submarine oil and gas pipeline become increasingly prominent,and regular inspection of submarine pipeline is particularly important.Therefore,a submarine pipeline inspection robot system based on CT technology to solve the problems such as low traditional manual inspection efficiency,high labor cost,low security and backward inspection methods.Based on the platform of ROV robot,carrying CT scanner as an external detection device,the system is used for non-invasive inspection of submarine pipeline,which is safe and harmless,with good economy,high mobility,and strong environmental adaptability.Compared with traditional technology,CT scanner’s external inspection technology used in the system avoids the damage to the external protective layer of the pipeline in the measurement of pipeline wall thickness.Meantime,it can provide the tomography of the pipe wall and the composition of the sediment material on the inside wall,which fills the gap in this technical field in China.According to the test,the robot has the characteristics of stable adsorption,flexible movement,and clear pipeline CT scanning image,and can realize the intelligent inspection of submarine pipeline.

In-Line Inspection of Pipeline Defects Detection Using Ring-Type Laser

Pipeline plays a vital role in transporting fluids like oils, water, and petrochemical substances for longer distances. Based on the materials they carry, prolonged usage may cause the initiation of defects in the pipeline. These defects occur due to the formed salt deposits, chemical reaction happens between the inner surface and the transferring substance, prevailing environmental conditions, etc. These defects, if not identified earlier may lead to significant losses to the industry. In this work, an in-line inspection system utilizes the nondestructive way for analyzing the internal defects in the petrochemical pipeline. This system consists of a pipeline inspection robot having two major units namely the visual inspection unit and the power carrier unit. The visual inspection unit makes use of a ring-type laser diode and the camera. The laser diode serves as a light source for capturing good quality images of inspection. This unit is controlled by the Arduino in the power carrier unit which provides the necessary movement throughout the pipe. The inspected images captured by the camera are further processed with the aid of NI vision assistant software. After applying the processing function parameters provided by this software, the defect location can be clearly visualized with high precision. Three sets of defects are introduced in a Polylactide (PLA) pipe based on its position and angle along the circumference of the pipe. Further, this robot system serves as a real-time interactive image synchronization system for acquiring the inspected images. By comparing the actual and calculated defect size, the error percentage obtained was less than 5%.

面向应用于林业采运输油管道检测的水下机器人的设计

为应用于林业采运输油管道的自主巡检,进行水下林业采运输油管道的定期巡检工作,设计了一款面向应用于林业采运输油管道检测的水下机器人。介绍了水下机器人的机械结构部分、控制部分、管道巡检部分设计。水下机器人使用的是STM32F407ZGT6单片机作为主控MCU,使用Open MV作为视觉电路板。经过实验验证,设计的水下机器人可以完成采运输油管道的巡检工作。

基于计算机视觉的管道机器人导航与目标识别

随着社会的不断发展,计算机、人工智能等先进技术愈加成熟。在人工智能技术的支撑下,管道机器人的性能不断完善,其中基于计算机视觉的管道机器人不仅能够根据运行需求对运动路线进行导航,还能够对目标信息进行有效识别。管道机器人企业只有不断加强对计算机视觉、导航及目标识别等技术的研发,才能使管道机器人在各行各业中发挥重要的作用。文章将围绕机器人视觉概述、基于计算机视觉的管道机器人导航与目标识别等方面进行具体的研究及分析。

仿生双爪式管道攀爬机器人设计与分析

针对燃气与管道工程等领域的高空作业,设计了一种永磁铁辅助式具有可调步距的蠕动和翻转两种步态的双夹持器仿生攀爬机器人。为防止机器人出现滑移和翻转倾覆失稳情况,对其进行了力学分析;根据机器人构型对其进行了运动学与攀爬步态分析;对蠕动攀爬步态进行直线路径规划,并在SOLIDWORKS MOTION环境下对其两种步态进行了运动仿真。样机试验说明了机器人在蠕动和翻转两种步态下均具有良好的稳定性,两种步态配合可实现障碍物的翻越。该机器人在高空管道领域作业方面具有较好的应用价值。

管道机器人取能模块建模与几何参数仿真分析

管道机器人在工作过程中,受到线缆长度或蓄电池容量的影响,工作时间会受到限制。为了使机器人在管道内能够持续地工作,设计了一款能在管道内部将流体动能转化为电能的取能模块。叶轮在取能模块中起到将流体动能转化为机械能的作用,是整个模块的核心部分。针对不同参数的叶轮进行建模,并对叶轮进行CFD仿真分析。进而能分析叶轮在管道内部的受力情况以及叶轮形状等参数对于管道内部流场的影响。根据受力情况可校核叶轮的强度,并根据管道内部流场的变化进行叶轮的选型。

管道机器人超声测量轮廓重建方法的研究

针对大型管道内生物附着物状态的高精度测量需求,提出一种利用齐次变换的轮廓重建方法,通过坐标变换使偏移轮廓的坐标校正回准确轮廓的坐标,消除运动位置偏差引起的轮廓测量误差。通过建立管道超声测量实验装置进行实验验证,得到偏移重建后产生的绝对误差为9 mm、相对误差为2.36%,偏转重建后产生的绝对误差为6 mm、相对误差为1.6%,误差落在超声检测系统的厘米级分辨率之内。后续可以通过提高超声检测系统的分辨率提高轮廓检测精度。该方法可以应用于水下管道轮廓检测以及水下机器人基于轮廓的自动定心探测。

一种矿用管道检测机器人设计及牵引性能分析

针对瓦斯抽采管道破损泄漏检测问题,设计了一种具有管道检测和运动控制功能的螺旋式矿用管道检测机器人,介绍了该机器人的结构和检测与控制系统方案。建立了机器人在管道中运行的力学分析模型,并通过动力学仿真研究了影响机器人牵引性能的因素,结果表明:机器人在管道内运行时的牵引力与管道材质、螺旋角、管壁与驱动轮之间法向力有关;机器人在不同材质的管道中运行时最佳螺旋角不同,在相同材质的管道中运行时,无介质运输情况下牵引力高于有介质运输情况;机器人牵引力随法向力的增大而增大,但最佳螺旋角无明显变化;随着螺旋角增大,牵引力先增大后减小,螺旋角为40°时牵引力最大。为提高机器人通过弯管时的性能,提出一种变螺旋角过弯策略,即机器人主动控制螺旋角随螺旋运动单元转动以正弦式规律变化,使管道内侧的螺旋角小于外侧。搭建机器人测试平台对矿用管道检测机器人进行测试,结果表明:机器人在直管中运行的最佳螺旋角为40°;可通过增加法向力来提升机器人的牵引性能;采用变螺旋角过弯策略时,机器人在弯管中的通过性能和平稳性优于定螺旋角过弯。

城镇聚乙烯燃气管道内检测机器人技术研究进展

国内城镇聚乙烯燃气管道主要采用埋地安装方式。在长期使用过程中,为及时发现管道老化、内部缺陷问题,需要使用管道机器人进行全面检测。文中按照机器人的运动类型分类介绍了国内外管道机器人的研究进展;介绍了聚乙烯管道的特性以及现有聚乙烯管道检测技术的发展现状;研究了目前城镇聚乙烯管道检测存在的主要问题,最后提出实现机器人与多种检测技术联合使用将对未来城镇聚乙烯燃气管道内检测的发展有重要意义。

一种小型履带式管道机器人的研究与设计

针对通风管道人工探查不便的现状,设计了一款专用的小型履带机器人。该机器人通过合理的结构设计,可以在狭窄的管道内实现爬坡和越障功能。开发了基于树莓派和STM32的控制系统,设计了整个机器体的硬件电路和各模块的控制程序,利用Qt Creator软件创建了便于控制与接收数据的上位机界面。通过光纤通信实现上位机和机器人的数据互通。机器人搭载的摄像头模块和轮速计可以在复杂的管道环境中实现定位功能。经过实验与数据采集,表明该机器人整体功能完善,在实际工作环境中运行平稳,能够满足管道机器人的工作要求。

基于振动响应分析的海底管道悬空内检测研究

铺设于海床中的海底管道常因洋流冲刷、船舶锚拽等自然或人为因素而处于悬空状态,易造成管道变形、腐蚀、损伤和开裂泄漏等问题,严重影响管线安全。针对DN200海底管道的悬空内检测,设计了一种内检测机器人并对其进行了动力学分析。同时,联合ANSYS与ADAMS软件建立了柔性管道-土耦合模型,开展了悬空管道内检测仿真分析。采用快速傅里叶变换和短时傅里叶变换方法对内检测机器人在复杂激励耦合条件下的振动响应信号进行处理,通过分析机器人的振动加速度实现了对悬空管段的有效识别。研究结果为油气管道悬空内检测提供了新思路。

复杂干扰下的管沟机器人内外环滑模自抗扰控制

管沟机器人是一种运行在排水管道,公路排水渠的欠驱动差分移动机器人,针对管沟机器人在实际环境中受到的复杂环境干扰,为了使管沟机器人具有更好的运动控制性能,提出了一种内外环的滑模自抗扰控制方法;首先对管沟受到的复杂环境干扰进行分析,将管沟机器人受到的复杂环境干扰解耦成横向和纵向干扰,建立出在干扰情况下的运动学模型;依据理想运动学模型建立出外环的滑模控制器,得出理想控制律,依据干扰运动学模型建立扩张状态观测器,观测出环境干扰数值,从而建立内环的滑模控制器,利用观测值修正外环的理想控制律;同时利用Lyapunov稳定性原理对系统进行分析,最后搭建了Matlab的Simulink模型进行仿真验证,最终证明了所提出的方法具有较强的鲁棒性和运动控制性能。