*Models and Technologies for Smart, Sustainable and Safe Transportation Systems*


To understand the differences between each SAE level, guidelines written by AdaptIVe (a project co-founded by European Commission) [9] have been taken into account. In the following a brief explanation for each SAE level is reported:


In current research and practice SAE levels are grouped into 2 classes: 012 and 345 as it can be seen within the **Figure 1**.

Still, several considerations about the relationships between kinds of sensors available on a vehicle and SAE Levels support a 3-class meta-classification useful to effectively support specification and calibration of models for transportation systems analysis.

**Table 1** shows the relationship between SAE Levels and types of sensors, supporting the 2-class meta-classification in **Figure 1**: Human driving vs. Automated driving. It could be noticed indeed that there is a huge difference between the type

**207**

**Table 2.**

shown below.

**Table 1.**

SAE level 5.

*Advanced Vehicles: Challenges for Transportation Systems Engineering*

of sensors installed in vehicles of each level. Note that the ultrasonic sensors are used only for parking maneuvers and not for drive assistance, thus they will not be

Image sensors and processors N N Y Y Y Y Radar sensors and systems N Y Y Y Y Y Lidar sensors and systems N N N Y Y Y Ultrasonic sensors and systems N Y Y Y Y Y

From these considerations, it is possible to see why many authors choose to use

**Human driving Automated driving**

**SAE 0 SAE 1 SAE 2 SAE 3 SAE 4 SAE 5**

• Human Driver: as shown in **Figure 1**, the vehicle certified within SAE Level 0 to Level 2 is in this macro class. Even if they show some technological differences between each level, in this type of vehicles the driving function is still human related. Hence, the currently available models for transport systems analysis [11] can almost straightforwardly be applied to these vehicles;

• Automated Driving System: the other levels are defined this class; the types of vehicles in this class are still at a prototypal stage, but it can easily be antici-

This meta-classification is probably over-simplified: at a closer look, vehicles in the "Automated Driving System" class cannot be conceived as homogeneous, as

In addition to sensors application range, by studying the SAE Levels definitions [10], it's possible to see that SAE Level 3 and SAE Level 4 vehicles still need a human driver compare to SAE Level 5. The human driver function within this level represents only a safeguard measure in emergency conditions or both SAE Levels: both presents different reaction times for the takeover, but the description used for the possible action that can be made by the driver during the travel are too permissive for the human driver and their reaction time. On the other hand, SAE Level 5 vehicles do not need a human driver at all, not even a steering wheel (as show in some prototype vehicle that have the possibility to hidden it), leaving all the control function to the vehicle. Starting from those considerations about the control of

Radar sensors and systems 200 [m] 200 [m] 200 [m] Image sensors and processors 250 [m] 250 [m] 200 [m] Lidar sensors and systems 150 [m] 150 [m] 100 [m]

*Relationship between automated driving SAE levels (3 to 5) and ranges of sensors.*

First, looking at the relationship between Automated Driving SAE Levels (3 to 5) and ranges of sensors, as shown in **Table 2**, it can easily find out that application ranges of sensors for SAE levels 3 and SAE Level 4 and quite different from those for

**SAE 3 SAE 4 SAE 5**

pated that new models need to be studied and developed.

*DOI: http://dx.doi.org/10.5772/intechopen.94105*

further considered within the following.

*Relationship between SAE levels and types of sensors.*

two macro classes, to group SAE Levels [10]:


*Advanced Vehicles: Challenges for Transportation Systems Engineering DOI: http://dx.doi.org/10.5772/intechopen.94105*

#### **Table 1.**

*Models and Technologies for Smart, Sustainable and Safe Transportation Systems*

To understand the differences between each SAE level, guidelines written by AdaptIVe (a project co-founded by European Commission) [9] have been taken into

• Level 2: more electronic devices for security, the driver is helped in some

• Level 3: in a smart road, the vehicle is supervised by human driver that takes

• Level 4: in a smart road, the vehicle is still supervised by the human driver, but

In current research and practice SAE levels are grouped into 2 classes: 012 and

Still, several considerations about the relationships between kinds of sensors available on a vehicle and SAE Levels support a 3-class meta-classification useful to effectively support specification and calibration of models for transportation

**Table 1** shows the relationship between SAE Levels and types of sensors, supporting the 2-class meta-classification in **Figure 1**: Human driving vs. Automated driving. It could be noticed indeed that there is a huge difference between the type

account. In the following a brief explanation for each SAE level is reported:

• Level 1: some electronic devices but the driver is still human,

maneuvers, but it still has the main control of the vehicle,

• Level 0: no electronic device and human driver,

control of the vehicle in case of emergency,

the driver can make other actions,

• Level 5: completed automated vehicle.

345 as it can be seen within the **Figure 1**.

**206**

systems analysis.

**Figure 1.** *SAE levels.* *Relationship between SAE levels and types of sensors.*

of sensors installed in vehicles of each level. Note that the ultrasonic sensors are used only for parking maneuvers and not for drive assistance, thus they will not be further considered within the following.

From these considerations, it is possible to see why many authors choose to use two macro classes, to group SAE Levels [10]:


This meta-classification is probably over-simplified: at a closer look, vehicles in the "Automated Driving System" class cannot be conceived as homogeneous, as shown below.

First, looking at the relationship between Automated Driving SAE Levels (3 to 5) and ranges of sensors, as shown in **Table 2**, it can easily find out that application ranges of sensors for SAE levels 3 and SAE Level 4 and quite different from those for SAE level 5.

In addition to sensors application range, by studying the SAE Levels definitions [10], it's possible to see that SAE Level 3 and SAE Level 4 vehicles still need a human driver compare to SAE Level 5. The human driver function within this level represents only a safeguard measure in emergency conditions or both SAE Levels: both presents different reaction times for the takeover, but the description used for the possible action that can be made by the driver during the travel are too permissive for the human driver and their reaction time. On the other hand, SAE Level 5 vehicles do not need a human driver at all, not even a steering wheel (as show in some prototype vehicle that have the possibility to hidden it), leaving all the control function to the vehicle. Starting from those considerations about the control of


**Table 2.**

*Relationship between automated driving SAE levels (3 to 5) and ranges of sensors.*
