=Paper= {{Paper |id=Vol-3114/paper8 |storemode=property |title=Survey on Testing of Autonomous Driving Systems |pdfUrl=https://ceur-ws.org/Vol-3114/paper-08.pdf |volume=Vol-3114 |authors=Wenjie Chen,Zeyu Ma,Chao Wang,Mingang Chen,Lizhi Cai |dblpUrl=https://dblp.org/rec/conf/apsec/ChenMWCC21 }} ==Survey on Testing of Autonomous Driving Systems== https://ceur-ws.org/Vol-3114/paper-08.pdf
 Survey on Testing of Autonomous Driving Systems
           Wenjie Chen                                              Zeyu Ma                                              Chao Wang
   Software Engineering Institute                        Software Engineering Institute                         Software Engineering Institute
Shanghai Key Laboratory of Computer                   Shanghai Key Laboratory of Computer                    Shanghai Key Laboratory of Computer
   Software Testing & Evaluation                         Software Testing & Evaluation                          Software Testing & Evaluation
  Shanghai Development Center of                        Shanghai Development Center of                         Shanghai Development Center of
   Computer Software Technology                          Computer Software Technology                           Computer Software Technology
          Shanghai, China                                       Shanghai, China                                        Shanghai, China
        cwj@sscenter.sh.cn                                    mzy@sscenter.sh.cn                                      wc@sscenter.sh.cn

           Mingang Chen                                            Lizhi Cai
   Software Engineering Institute                        Software Engineering Institute
Shanghai Key Laboratory of Computer                   Shanghai Key Laboratory of Computer
   Software Testing & Evaluation                         Software Testing & Evaluation
  Shanghai Development Center of                        Shanghai Development Center of
   Computer Software Technology                          Computer Software Technology
          Shanghai, China                                       Shanghai, China
        cmg@sscenter.sh.cn                                     clz@sscenter.sh.cn

   Abstract—Before autonomous driving vehicles are                             II. TESTING PROCESS OF AUTONOMOUS DRIVING SYSTEMS
commercialized, they need to undergo a series of rigorous tests.
This paper first proposes the general process of autonomous                       Autonomous driving system testing is an important
driving system testing, and then summarizes the research                      procedure in the development process of autonomous vehicles,
progress of autonomous driving vehicle testing from the model,                it mainly focuses on testing the functional suitability,
simulation, network, and vehicle levels, and analyzes the                     reliability and security defined in the ISO/IEC 25010 standard.
characteristics of various testing technologies. Finally, this                The testing process of the autonomous driving system
paper gives suggestions on the development of autonomous                      includes model testing, simulation testing, cybersecurity
driving testing technology.                                                   testing, and field testing, as shown in Fig. 1. Model testing,
                                                                              simulation testing and field testing mainly test functional
   Keywords—autonomous driving,               adversarial     examples,       suitability and reliability of the autonomous driving system,
simulation testing, cybersecurity                                             and cybersecurity testing mainly tests security of the
                                                                              autonomous driving system.
                         I. INTRODUCTION
    In recent years, the pervasive and tremendous
breakthroughs of deep neural networks (DNNs) promote the                                                  Model testing
development of autonomous driving technology. However,
sometimes it is difficult to guarantee the reliability of the                                           Simulation testing
autonomous driving system. Banerjee et al. investigated the
                                                                                           Testing
causes of 5,328 failures from autonomous driving systems of                                Results         Cybersecurity          Scenario
12 AV manufacturers[1]. As high as 64% of the failures were                                                   testing             Database
found to be caused by the bugs in the machine learning system.
The industry and academia have strived to improve the safety                                               Field testing
of the autonomous driving system, they have done a lot of
research on testing autonomous driving system.
    This paper summarizes the current research of
autonomous driving testing technology from four aspects:                                Fig. 1. Testing process of autonomous driving systems
model testing, simulation testing, cybersecurity testing, and
field testing, combined with the system and software quality                      The testing process of the autonomous driving system is a
model defined in the ISO/IEC 25010 standard. Research on                      continuous cycle. During model testing, the perception model
model testing is mainly focused on the adversarial attack. At                 is tested using test data sets and adversarial examples. Then
present, there are already some works that can generate                       the simulation platform is used to test the autonomous driving
adversarial examples for street signs and billboards, leading to              system and each control unit. Cybersecurity testing mainly
misclassification of the autonomous driving system. In terms                  focuses on the network security of the autonomous driving
of simulation testing, many companies have developed                          system and its interface. Field testing is to test the autonomous
simulation platforms and scenario databases. The research of                  driving vehicle in a proving-ground. During the test, a
cybersecurity testing focuses on the vulnerability detection                  scenario database composed of environment, traffic
and data protection of the terminals and interfaces in the                    participants, sensors, and other data is generated. The results
vehicle network. Field testing mainly focuses on the                          of tests will also be used to update the scenario database, such
construction of a proving ground for autonomous driving.                      as adding some newly discovered dangerous scenes.




    This work was funded by Ministry of Science and Technology of the
People's Republic of China Program (2018YFB1403405) and Science and
Technology Commission of Shanghai Municipality Program
(21511101204).
Copyright © 2021 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
  III. TESTING TECHNOLOGY FOR AUTONOMOUS DRIVING
                           SYSTEMS

A. Testing for autonomous driving models
    Testing of autonomous driving system models is
performed by testing datasets, adversarial examples, and other
methods against perception models. Most current perception
models are implemented by DNNs, but due to the large
dimensions of input data for models, DNNs are vulnerable to
adversarial examples, which is a great concern for the prospect                 Fig. 2. Attacking stop signs with stickers[6]
of autonomous driving. Many studies have shown that the
object detection model used for autonomous driving can be              Aishan Liu et al. proposed PS-GAN, which can generate
easily deceived by the existing adversarial attack methods,        adversarial patches, innovatively combining GAN network
thereby causing errors in autonomous driving decision-             and attention mechanism[7]. PS-GAN can capture the
making.Current adversarial attack methods in the field of          sensitivity of spatial distribution to obtain the optimal attack
autonomous driving are mainly divided into attacks on the          locations in order to enhance the attack capability of the
object detection model and attacks on LIDAR.                       patches and also ensure a reasonable appearance, as in Fig. 3.
    In 2017, a team of researchers at Columbia University          However, this method does not guarantee that the patch is
proposed DeepXplore[2], an automated DNN testing system            always on the target object.
that uses several existing test inputs as seeds, then modifies
the test inputs in a continuous loop iteratively through a
gradient ascent method to maximize the difference between
the output of the model under test and the output of other
similar models. Eventually, this system is able to generate a
new set of test data, which can trigger errors in the judgment
of the model under test. Experiments on the Udacity challenge
dataset showed that the system is capable of making the                   Fig. 3. The adversarial patches generated by PS-GAN[7]
DNN-based autonomous driving systems' prediction of the
car's steering angle incorrect by changing the lightness and           Zelun Konget al. proposed PhysGAN, an algorithm that
darkness of the input images, adding noise, and so on. The         generates adversarial examples with physical world resilience
same group followed up with DeepTest[3], removing the              for autonomous driving systems in a continuous manner[8].
requirement that DeepXplore must provide multiple DNNs             Unlike PS-GAN, the input to PhysGAN is a given scene (e.g.
with similar functions. DeepTest also makes some changes for       the content of a billboard, as in Fig. 4), so the generated
the generation of test data for autonomous driving systems,        adversarial examples are more realistic. What differs from
resulting in a more efficient system for generating data for       other adversarial attack methods which aim at detection
extreme scenarios.                                                 classifiers is that PhysGAN attacks autonomous driving
                                                                   navigation systems, which are regression models. So the
    DeepXplore and DeepTest can generate a large number of         authors use the mean squared error and the maximum error of
adversarial examples, but these are very different from real       the angle of autonomous driving navigation evaluate the result.
scenes, and many extreme scenes such as rainy and foggy days
are tough to generate by simple image transformation.
DeepRoad[4] uses Generative Adversarial Networks (GAN)
to generate more realistic transformed images of rainy and
snowy days, compare the steering angle prediction results of
the generated images with results of the original images,
which can find the scenes that cause errors of DNN in the
autonomous driving.
    Zhou et al. proposed DeepBillboard, which generates real-
world adversarial examples of billboards that could trigger
steering errors in autonomous driving systems[5]. It                Fig. 4. Attacking autonomous driving navigation systems via PhysGAN
                                                                                          on the McDonald's ads[8]
demonstrates the possibility of generating real physical-world
adversarial examples for actual autonomous driving systems.            The above studies aim at vision-based autonomous driving
Kevin et al. perform a physical-world robustness attack on         systems, but LiDAR-Adv[9], a joint study of University of
parking road signs (by sticking adversarial patches at specified   Michigan, UIUC, and Baidu, breaks through LiDAR systems.
locations on the road signs) to misclassify stop signs as other    The researchers connected perturbations of a 3D target to a
signs of the specified category with 100% probability, as in       LiDAR scan (or point cloud) by modeling a differentiable
Fig. 2[6]. The authors proposed the RP2 algorithm: Firstly,        LiDAR renderer. They then used the differentiable proxy
build a model to quantify the target object's physical changes     function to produce 3D feature aggregations and designed
(including changes in distance, angle, illumination, etc., and     different losses to ensure that 3D adversarial examples were
transformations such as random cropping of images and              smooth. In a specific experiment, the researchers compared a
changes in luminance), then construct a mask of the target         normal box with a 3D printed adversarial example on the
object to discover "vulnerable regions" on which the attack is     Apollo Autopilot system. They found that the LIDAR-
achieved by masking.                                               equipped car did not detect the target until it approached the
adversarial example. In contrast, the car detected the normal              Tencent and Baidu have also released their own databases of
box at a long distance.                                                    autonomous driving scenarios.
    The University of Toronto, Princeton University in                         2) Simulation platform
conjunction with Uber also proposed a generic 3D adversarial                   The autonomous driving simulation platform is a system
object generator to fool LIDAR detectors[10]. In particular,               that tests autonomous driving functions by simulating traffic
the authors placed a generated pseudo-object on top of any                 scenes, vehicle movements, and sensor signals. Its main
target vehicle to completely hide the vehicle, resulting in an             functions include restoring static scenes and dynamic scenes,
80% success rate of not being detected by LIDAR detectors,                 camera and radar simulation, and vehicle dynamics simulation.
as shown in Fig. 5.                                                        At present, many companies and institutions have developed
                                                                           their autonomous driving simulation platforms.
                                                                               Carla[12] is an open source free autopilot simulator based
                                                                           on unreal engine. It supports flexible configuration of sensors,
                                                                           environmental states, dynamic and static traffic participants
                                                                           and maps, and can control simulated vehicles through Python
                                                                           or C language API. Autoware[13] is an open source software
                                                                           for automatic driving technology research. It includes four
                                                                           modules: localization, detection, prediction and planning, and
                                                                           control. It supports path planning, traffic signal detection, lane
                                                                           detection, virtual reality and other functions. PreScan[14] is a
                                                                           widely used vehicle driving simulation software product of
                                                                           Siemens. It supports the simulation of multiple functions such
                                                                           as camera, radar, LiDAR, GPS, and vehicle-to-vehicle
                                                                           communication, and can simulate simple traffic scenarios.
   Fig. 5. Placing an antagonistic object on the target vehicle made the
                                                                           SiVIC[15] is similar to PreScan, but it can provide more
                    vehicle "invisible" to LIDAR[10]                       realistic and complete sensor models. Google developed the
                                                                           simulation platform Carcraft, based on the scenario data
B. Simulation testing for autonomous driving systems                       collected by Waymo, combined with high-precision map
                                                                           information, to realistically simulate the real traffic
    The simulation test is to test the autonomous driving
                                                                           environment. NVIDIA released the cloud-based NVIDIA
system and each control unit through the simulation platform.
                                                                           Drive Constellation simulation system in 2018, which can
Currently, about 90% of autonomous driving tests are
                                                                           generate realistic data, create various test environments,
completed through simulation platforms. Both Scenario
                                                                           simulate various weather conditions such as rain and snow,
database and simulation platform are required for simulation
                                                                           simulate different roads and terrains, and simulate dazzling
testing.
                                                                           light during the day and limited vision at night. Microsoft
    1) Creating Scenario Database                                          open-sourced the cross-platform Unreal Engine simulator
    A scenario is the overall description of the autonomous                AirSim in 2017, which supports simulations of drones and
vehicle and environment components over a period, which is                 autonomous driving. It can create a highly realistic traffic
abundant and complex. The scenario database is a database                  environment and simulate vehicles and sensors. LG Silicon
composed of a series of test scenarios that meet certain test              Valley Lab released the open-source autonomous driving
requirements. The construction of the scenario database is                 simulator LGSVL Simulator in early 2019, which supports
generally divided into four steps[11]: data collection, data               sensor simulation and editable maps, vehicles, weather, traffic
cleaning, information labeling, and scenario clustering. The               flow, pedestrians, etc.
source of scenario data mainly includes real-world driving                     Tencent released the autonomous driving simulation
data and simulation data synthesized from real-world driving               platform TAD Sim in 2018, which combines professional
data. The test results of the simulation test will also be used to         game engines, industrial level vehicle dynamics models,
update the scenario database as required.                                  integrated virtual and real traffic flow and other technologies.
    At present, many auto companies and autonomous driving                 Baidu's self-developed autonomous driving simulation system
solution providers have established their own scenario                     AADS includes a data-driven traffic flow simulation
databases. Waymo collects simulation scenarios based on                    framework and a scene picture synthesis framework based on
field tests. After testing autonomous vehicles on public roads             image rendering. Researchers of Jilin University
and proving ground, Waymo accumulates thousands of                         independently developed the PanoSim, a virtual autonomous
scenario data, creates virtual scenarios based on these data,              driving test platform[16]. They analyzed the driving habits of
and produces more scenarios by modifying scenario                          drivers based on the platform and proposed ADAS control
parameters. Waymo has released a database of more than one                 strategies that consider different driving habits.
thousand scenarios. Automotive Data of China Co., Ltd. has
                                                                           C. Cybersecurity testing for autonomous driving systems
initially built a simulation testing scenario database that
includes nearly 500,000 kilometers of driving data and traffic                 The autonomous driving system is deployed in the
rules, covering important cities such as Beijing, Tianjin, and             Intelligent Connected Vehicle(ICV), which can not only assist
Shanghai. China Automotive Engineering Research Institute                  or replace drivers to control a vehicle through advanced
Co., Ltd. released the "China Typical Scenario Database                    onboard sensors, controllers, actuators, and other devices but
V2.0" in 2019, including hundreds of standard traffic rules                also integrate modern communication and network
scenarios, 3,000 empirical scenarios, 50,000 functional                    technologies to realize Vehicle-to-everything(V2X), complex
scenarios, and 150 accident scenarios. Companies such as                   environmental perception, decision making and cooperative
control of multi-vehicle, etc. The vehicle network technology                                                     To test the four types of cybersecurity testing objects for
provides the possibility that crackers hack into the                                                          autonomous driving systems, several researchers not only
autonomous driving system or ICV system. Crackers can slow                                                    applied existing traditional effective and valuable
down, stop the engine, brake, or do other malicious operations                                                cybersecurity testing methods to cloud service platforms and
to the vehicles by hacking into the cloud account. They may                                                   mobile phone terminals, but also proposed testing methods for
also hack into the mobile application to take over the control                                                the items of autonomous driving systems that require special
of vehicle such as unlocking and starting engine remotely;                                                    attention. Wu Lingyun et al. proposed a random forest-based
implant malicious files into the in-vehicle networking (IVN)                                                  CAN bus message anomaly detection method model, which
through USB storage media to control the vehicle, etc.                                                        effectively detects anomalous data on ICV and improves
Yoshiyasu Takefuji listed several cybersecurity incidents,                                                    vehicle operation security[18]. Mazloom S et al. created a
such as white hat hackers stopped the engine of a car on the                                                  malicious demo application, loaded on a mobile terminal. It
highway through a remote man-in-the-middle attack in 2015;                                                    uses the open MirrorLink interface on an IVI to connect to a
Ford car's parking assistance module could be forced to                                                       mobile phone and discovers a heap overflow vulnerability that
intervene the control of steering wheel through the CAN                                                       allows an attacker to obtain the control flow of a privileged
command named "0x0081"[17].                                                                                   process executing on the IVI[19]. It will further allow
                                                                                                              malicious attacks on the controller of the autonomous driving
    The frequent occurrence of security accidents has                                                         system. Testers can use the same principle to test whether the
accelerated the in-depth examination of cybersecurity issues                                                  dangerous interface of IVI has been closed using the relevant
of ICV. The security of autonomous driving systems requires                                                   Payload.
the support of layered distributed technology, including the
security of in-vehicle module systems, network-side                                                           D. Field testing for autonomous driving systems
interaction and cloud information processing. The security of                                                     Field testing is to test the autonomous vehicle on the real-
each layer guarantees the security of ICV and connected                                                       world road, typically in a proving ground. The autonomous
vehicle system, and ensures the safety of the autonomous                                                      vehicle must be tested in many scenarios and environments in
driving system ultimately.                                                                                    a limited field.
                                                                                                    Backend




                                                                                                                  The United States and the European Union have built
 Autonomous driving system cybersecurity




                                           Mobile phone terminal         Cloud service platform
                                                                                                              some proving ground for autonomous driving testing. The
                                                                                                              Smart Road was built in Virginia by renovating part of the
                                                       Communication Network
                                                                                                              highway, which is 2.2 miles long and can simulate rainy and
            testing objects




                                                                                                    Network




                                                             Cellular Network                                 foggy weather by spraying water mist. The Mcity proving
                                                                                                              ground in Michigan contains pavements of different materials,
                                                       In-vehicle Network (CAN Bus)
                                                                                                              and is equipped with abundant traffic signs, signal lights,
                                                                                                              tunnels, and other traffic elements. Google rents the Castle Air
                                                           In-vehicle terminal                                Force Base in California to test its autonomous vehicles. There
                                                                                                              are various streets, highways, traffic lights, traffic
                                                                                                    Car




                                            T-Box          IVI            ECU         GateWay/...             roundabouts, etc. inside the proving ground, as well as rainy
                                                                                                              weather simulators. The AstaZero Proving Ground in Sweden
               Fig. 6. Objects of autonomous driving system cybersecurity testing
                                                                                                              includes urban roads, highways, multi-lane parallel road,
                                                                                                              roundabouts and intersections, and has become a research and
    According to the structure of vehicle security operation                                                  development platform for autonomous driving safety
center (VSOC) defined in the white book, "Setting the                                                         technology. Shanghai, Hangzhou, Wuhan, Shenzhen and
Standard for Connected Cars' Cybersecurity", the objects of                                                   some other cities in China also plan to build proving ground
testing autonomous driving system cybersecurity can be                                                        for autonomous driving testing.
classified into cloud service platform, mobile phone terminal,
                                                                                                                                    IV. CONCLUSION
in-vehicle terminal, and communication network (Fig. 6).
Specific testing points for these objects include the following:                                                  Testing and verifying the safety of autonomous driving
                                                                                                              systems is an important prerequisite for running autonomous
    a) Cloud service platform testing concerns more about the                                                 vehicles on the road. The difficulty of testing is increasing as
traditional Web vulnerability and the transmission security                                                   the level of autonomous driving increases. Currently, the
between the cloud and the other two terminals;                                                                industry and academia have carried out a lot of research on
    b) Mobile phone terminal has become the standard                                                          testing autonomous driving systems and developed
configuration of ICV so that testers should evaluate whether                                                  corresponding tools and technologies to test autonomous
the communication key and communication protocol between                                                      driving models, systems, networks, and vehicles. A lot of
the mobile and vehicle terminal can be cracked by                                                             achievements have been made in adversarial example
technologies, analyze the communication protocol, and use it                                                  generation, simulation platform development, network
to forge malicious requests for vehicle control;                                                              vulnerability analysis and proving ground construction.
                                                                                                              However, there are still some unresolved problems in
    c) In-vehicle terminal testing objects include In-Vehicle                                                 autonomous driving system testing. For example, the
Infotainment (IVI), Telematics-Box (T-Box), sensors,                                                          cooperation mechanism of developing the scenario database
external interfaces, and other components. Generally, IVI, T-                                                 is still inefficient, and the standard of autonomous driving
Box and other components contain operating systems, in-                                                       system evaluation is not established yet. In the future, it is
vehicle APPs, and a large number of third-party libraries;                                                    necessary to establish a set of testing standards and tool chains
    d) Communication networks are tested for authentication,                                                  for autonomous driving systems to provide forceful supports
transmission encryption, and protocol security.
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                                                                                      autonomous driving systems," arXiv:1907.05418, 2019.
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