Academic Journal of Science and Technology 
ISSN: 2771-3032 | Vol. 9, No. 1, 2024 

 

208 

Overview	of	Pipeline	Inspection	Robots	
Jingtao Tan, Yuan Yang, Zixuan Fan, Yifei Wang, Qiandi Zhou and Zhiwen Wang 

School of mechanical and electrical engineering, Southwest Petroleum University, Chengdu 637001, China 

 

Abstract: Pipelines are widely used in our daily life and industrial production, in order to solve the ensuring problem of 
pipeline failure, many kinds of pipeline inspection robots have appeared, and nowadays, pipeline robots have been widely used 
in various pipeline inspection and repair. This paper mainly discusses the importance of pipeline inspection robots in various 
pipeline fields, describes the technical characteristics of pipeline robots at home and abroad in recent years, and puts forward 
suggestions for the future development of pipeline robots in view of the existing problems, which is of reference significance for 
the future development. 

Keywords: A plumbing robot; Tube inspection; Developing the status. 
 

1. Introduction 
In modern society, pipelines have penetrated into many 

corners of our lives, providing convenience for the 
transmission of energy and materials and bringing great 
economic benefits. However, at the same time, problems such 
as aging, corrosion and clogging of pipelines also come along. 
Due to the special location of many pipelines, human beings 
cannot have direct access to them, which brings great 
challenges to pipeline inspection and maintenance work. 
Traditional inspection and maintenance methods, such as 
excavation and random sampling, are not only labor intensive 
but also inefficient. 

Since the beginning of the 1950s, since the domestic and 
foreign research on pipeline robots, pipeline robots have 
begun a rapid development, and now pipeline robots have 
been widely used in gas transmission, water diversion, 
petrochemical and thermoelectric steam transmission and 
other areas of pipeline inspection and maintenance. The 
research and application of pipeline robots can not only 
greatly reduce the workload of pipeline inspection and 
maintenance, reduce the labor intensity of workers, improve 
the efficiency of pipeline inspection and maintenance, but 
also reduce the cost of inspection and maintenance. 

2. Classification of pipeline robots 
According to the moving mechanism, the pipeline robots 

can be divided into roller mobile, Tracked mobile, peristaltic 
mobile, and liquid-driven, etc [1]. 

2.1. Roller mobile pipeline robot 
Roller mobile pipeline robots use rollers as a driving 

mechanism and move by motor. Roller drive has advantages 
such as high power transmission efficiency and stability of 
operation, which has become the main driving mode of 
pipeline robot [2]. 

Roller mobile pipeline robots are supported straight-in type 
and screw-driven type. Supported straight-in pipeline robot, 
as shown in Fig. 1, the axis of the pipeline robot roller is 
perpendicular to the centerline of the pipeline, the forward 
direction of the roller is the same as the direction of the 
pipeline, and it moves along the axis of the pipeline under the 
action of the driver [3]. 

 
Figure 1. Supported straight-in pipeline robot 

 
Spiral-driven pipeline robot, as shown in Fig. 2, the axis of 

the robot's rollers is not perpendicular to the axis of the 
pipeline, and there exists a certain angle a (helical climb angle, 
0<a<90°), the helical climb angle provides axial and 
circumferential partial velocity for the robot to move forward, 
and it advances along the pipeline in the putative form of a 
helix under the action of the actuator [3]. 

 
Figure 2. Screw-driven pipeline robot 

2.2. Tracked mobile pipeline robot 
A tracked mobile pipeline robot uses tracks as its traveling 

mechanism and moves using motor drives. Tracks provide 
stable support for the robot and increase the robot's ability to 
pass. Commonly, tracked pipeline robots can be categorized 
into double-tracked and triple-tracked depending on the 
number of tracks.  

Dual-tracked pipeline robot, as shown in Fig. 3. The 
double-tracked pipeline robot has a smaller structure and 
better flexibility, but it can't stick to the inner wall of the 
pipeline, and its movement in the pipeline is unstable and 
prone to tilting, and it's not suitable for occasions where the 



 

209 

slope of the pipeline is large [4]. 
 

 
Figure 3. Dual tracked pipeline robot 

 
A three-track pipeline robot, as shown in Fig. 4. The three-

track robot can adapt itself to the size of the pipeline by 
adjusting the device, so that the three tracks closely fit the 
inner wall of the pipeline to generate a large enough adhesion 
force, and ultimately provide greater forward momentum for 
the robot movement under the action of the actuator [5]. 

 

 
Figure 4. Three tracked pipeline robot 

 

2.3. Peristaltic mobile pipeline robot 
Peristaltic mobile pipeline robots are modeled after the 

peristaltic forward and backward movements of reptiles 
crawling on the ground. Peristaltic pipeline robots are highly 
redundant degrees of freedom motion robots that avoid the 
disadvantage of wheeled or tracked robots that cannot 
continue working after they have rolled over on their side [6]. 

2.4. Liquid-driven pipeline robot 
Fluid-driven pipeline robots utilize the pressure difference 

drive of the fluid to achieve motion in a pipeline filled with a 
medium, as shown in Fig. 5. Roller-type and crawler-type 
pipeline robots are more difficult to control the traveling 
speed and are prone to large fluctuations. In addition, they are 
limited in carrying energy, making it difficult to work for long 
periods of time inside pipelines. These problems severely 
limit the working time and working distance of pipeline 
robots. Fluid-driven pipeline robots, on the other hand, utilize 
the pressure of the fluid to achieve the walking function. This 
design makes it easier to accurately control its speed and 
enables it to travel stably, thus improving the overall 
performance of pipeline robots [7]. 

 

 
Figure 5. Liquid-driven pipeline robot 

3. Current Status of Research on 
Pipeline Robots 

3.1. Current status of pipeline robot 
development abroad 

Foreign research on pipeline robots can be traced back to 
the 1950s. With the development of industrialization in the 
West, the demand for inspection and maintenance of oil and 
gas pipelines gradually increased, and the demand for in-pipe 
robots also grew rapidly. J. VERTUT of France developed a 
wheel-legged in-pipe walking mechanism model IPRIV in 
1978, which realized autonomous walking in the pipeline 
despite its simple structure and single function, and had a 
profound impact on the development of pipeline robots. In the 
1870s, the United States rapid development of pipeline 
transportation, greatly enhancing the United States of 
America on the pipeline inspection equipment research needs. 
1962, the United States Knapp and Girard developed a robot 
for pipeline cleaning "pipeline pig". PIG is the most 
representative of the early pipe cleaning and inspection 
equipment, there is no autonomous drive capability, its 
forward power from the head and end of the fluid pressure 
difference, without the need for trailing cables or carrying 
batteries to drive, once can walk several hundred kilometers 
[8]. 

Islas-Garciaea et al. at the National Polytechnic Institute of 
Mexico developed a bionic type pipeline robot [9], as shown 
in Fig. 6. The robot uses rollers as a walking mechanism and 
is mainly used to detect and analyze the condition of 
underground drainage pipes in different highways in Mexico. 

 

 
Figure 6. Roller mobile pipeline robot 

 
A peristaltic drive mechanism for narrow pipes was 

designed by Tomonari Yamamoto et al. in Japan, as shown in 
Fig. 7. The robot achieves rapid motion through narrow ducts 
by a unique dual-chamber structure, and the mechanism 
achieves smooth bi-directional peristaltic motion by a 
combination of expandable silicone rubber and coil springs, 
which can be fully controlled by only two air supply lines [10]. 

 
Figure 7. Peristaltic pipe drive mechanism 

 
H. Torajizadeh, et al. at Kharazmi University, Iran, 

designed a spiral type of pipeline robot as shown in Fig. 8. 
The robot is capable of moving through any pipe in a 
predefined range of diameters at a variable helix angle and 
reporting any required data inside the pipe with the help of an 



 

210 

installed camera [11]. 
 

 
Figure 8. Spiral pipeline robot 

3.2. Current status of domestic development of 
pipeline robots 

Domestic research on pipeline robots started late, and the 
development of pipeline robots still has a certain gap 
compared with developed countries. However, with the rapid 
development of China's industry, as well as the importance of 
the field, there has been considerable progress. 

In 1989, Deng Zongquan and others from Harbin Institute 
of Technology were the first to carry out research on mobile 
robots in the pipeline, which was mainly used for automated 
inspection of large-caliber pipelines [7]. Shanghai Jiao Tong 
University, Shanghai University and a large number of 
colleges and research institutions in the field of pipeline 
robotics also have more research results. 

Li Yin et al. from Shaoguan College designed a snake-
shaped pipeline robot [6], as shown in Fig. 9. The robot 
advances through the motion of peristalsis, a peristaltic cycle 
advances 0.145m, while using 57 two-phase stepper motors 
and STM32 control, which is able to realize the pipeline 
detection and unclogging work. 

 

 
Figure 9. Snake pipeline robot 

 
A fluid-driven pipeline robot was designed by Tao Shi et al. 

from Kunming University of Science and Technology, as 
shown in Fig. 10. The robot is a modular chain pipeline robot, 
which solves the problems of traditional fluid-driven robots 
with large structural volume and unpredictable friction main 
force[12]. 

 

 
Figure 10. Fluid-driven pipeline robot 

Liu Qingyou et al. from Southwest Petroleum University 
designed an active spiral-driven pipeline robot [13], as shown 
in Fig. 11. The robot consists of guide wheels, drive wheels, 
planetary gears, motors and other components, and STM32 is 
used as the central control unit. This pipeline robot solves the 
problems of passive spiral pipeline robot's small traction force 
and low mechanical transmission efficiency. 

 

 
Figure 11. Active screw-driven pipeline robot 

4. Problems with Pipeline Robots 
1) Adaptation and obstacle-crossing ability problem. In 

reality, pipelines have various shapes, such as reducers, bends, 
"T" pipes, etc. At the same time, there may be debris or 
defects in the pipeline, which may affect the work of pipeline 
robots. Therefore, how to improve the adaptability and 
passability of pipeline robots in various complex pipeline 
environments is an important direction for current and future 
research. 

2) Energy supply problem. Currently, pipeline robots 
mainly use electricity as their energy source. For cable-
trailing pipeline robots, when the working distance is far away 
or the internal environment of the pipeline is uneven, the 
friction between the cable and the pipeline wall increases and 
the length of the cable limits the working distance of the robot. 
For cable-less pipeline robots, batteries are generally used as 
the storage energy, which is limited by the size of the pipeline 
and the machine itself, the energy it carries is limited, also 
limiting its working distance. 

3) Signal transmission problem. Pipeline robots in the 
pipeline inspection and maintenance need to timely contact 
with the outside world, there are two main signal transmission 
methods, one is dragging the communication cable, the other 
is wireless signal transmission. Robot communication by 
dragging the communication cable in long-distance operation 
cable in the pipeline resistance will become very large, 
hindering the work of the robot. The wireless communication 
method is limited by the working environment of the pipeline 
robot, and the signal may be weakened by the medium in the 
pipeline, or by the pipeline itself, or by the environment 
outside the pipeline. 

4) Reliability issues. Pipeline robot due to its special 
working environment, if the robot fails in the pipeline or gets 
stuck in the pipeline and clogs the pipeline, it may cause 
greater economic losses. 

5. Conclusions 
After decades of development, pipeline robotics 

technology has gradually matured and is transitioning from 
experimental research to practical applications. With the 
continuous progress of science and technology, as well as 
more and more researchers' attention and investment in 
pipeline robotics, future pipeline robotics research will 
mainly focus on the following aspects: 

1) Intelligent: future pipeline robots will be more 



 

211 

intelligent, capable of autonomous perception, decision-
making and execution of tasks, with greater autonomy and 
adaptability. 

2) High performance: In order to adapt to more complex 
and harsh pipeline environments, pipeline robots need to have 
higher performance and greater adaptability. Future pipeline 
robots will use more advanced sensors, controllers and 
actuators to achieve more efficient and accurate detection and 
operation. 

3) Miniaturization: In order to access smaller pipelines, 
such as urban drainage pipes and oil and gas pipelines, future 
pipeline robots will be more miniaturized. Miniaturized 
pipeline robots can more easily enter small spaces for finer 
inspection and maintenance. 

4) Safety: The safety of pipeline robots is an important area 
for future research. Future pipeline robots will utilize safer 
and more reliable designs and technologies to ensure that they 
perform their tasks without causing damage to people and the 
environment. 

5) Remote control: Future pipeline robots will pay more 
attention to the development of remote control technology. 
Through remote control technology, operators can control 
pipeline robots in a safe and comfortable environment, 
realizing more efficient and safer operations. 

References 
[1] Yi Ding, Ruhong Wang, Chenying Jiang. The development of 

the pipeline robot and its application in packaging area. 
Packaging and Food Machinery, Vol. 27 (2009) No. 5, p. 128-
130. 

[2] Hongwei Yan, Yang Wang, Jianqiang Ma, et al. Analysis for 
dynamic characteristics of wheeled pipe robot in Elbow. 
Journal of Xi 'an Jiaotong University, Vol. 52 (2009) No. 8, p. 
87-94. 

[3] Zheng Zhang, Xin Wang, Tianxiang Jiang, et al. Research and 
simulation of key parameters for wheeled pipeline robot in 

elbow. Machinery Design & Manufacture, Vol. 30 (2023) No. 
4, p. 90-95. 

[4] Zenghui Liu, Zhengkuo Ma, Lei Peng. Research on Anti-roll 
mechanism of double-wheel crawler pipeline robot. 
Mechanical Manufacturing and Automation, Vol. 49 (2020) No. 
5, p. 142-145. 

[5] Xianggui Cui, Jizhong Zhang, Jinhua Jiang. Simulation 
analysis and optimal design of diameter-changing mechanism 
of tracked pipeline robot. Journal of Qingdao university, Vol. 
36 (2023) No. 2, p. 79-83. 

[6] Yin Li, Yunlong Miao, Qi Li. Structural design and motion 
analysis of a serpentine pipe robot. Robot Technique and 
Application, Vol. 20 (2023) No. 5, p. 30-35. 

[7] Yingjie Zhang. A survey of pipeline robot. Equipment 
Manufacturing Technology, Vol. 25 (2021) No. 6, p. 114-117. 

[8] Dezhao Qin, Yanfeng Li, Yongzhi Zhang. Research and 
development trends of robots in tubes. Industrial Control 
Computers. Vol. 34 (2021) No. 7, p. 31-35. 

[9] Islas-Garciae, Ceccarellim, Tapia-Herrerar, et al. Pipeline 
inspection tests using a biomimetic robot. Biomimetics. Vol. 6 
(2021) No. 1, p. 17-21. 

[10] Yamamotot, Sakamas, Kamimura. Pneumatic duplex-
chambered inchworm mechanism for narrow pipes driven by 
only two air supply lines. IEEE Robotics and Automation 
Letters, Vol. 5 (2020) No. 4, p. 5034-5042. 

[11] Torajizadeh, Asadirad, Mashayekhi et al. Design and 
manufacturing a novel screw‐in‐pipe inspection robot with 
steering capability. Journal of Field Robotics. Vol. 40 (2023) 
No. 3, p. 429-446. 

[12] Tao Shi, Ruibo Yuan, Yuran Shao, et al. The invention relates 
to the structure of a fluid driven pipeline robot optimization 
design and motion analysis. Journal of Chongqing University 
of Technology. Vol. 37 (2023) No. 9, p. 322-331. 

[13] Qingyou Liu, Yujia Li, Tao Ren, et al. An active helical drive 
in-pipe robot. ROBOT. Vol. 36 (2014) No. 6, p. 711-718.