# Steady-Speed Traffic Capacity Analysis for Autonomous and Human-Driven Vehicles
## 2 Experimental Campaign  
An experimental campaign was conducted at the ZalaZONE proving ground in Hungary, with the primary objective of assessing the performance of vehicles equipped with ACC systems. The campaign utilized a two-lane motorway section spanning 1.5 km, providing sufficient length for a comprehensive study. The runs were carried out on the designated motorway section to facilitate a controlled and replicable environment for testing ACC-equipped vehicles. This setup allowed researchers to collect valuable data on the behavior and effectiveness of ACC systems under various conditions. During the experiment, three distinct vehicles were selected with the basic information shown in Table 1, each equipped with different ACC sensor types:  
* **Subaru Levorg**: The Subaru Levorg was selected to represent a vehicle equipped with a camera-based ACC sensor (Eyesight). The front-mounted position of Eyesight allows the sensor to capture a wide range of visual information, including traffic conditions, lane markings, and potential obstacles, ensuring the ACC system's ability to make informed decisions in real time.
* **Volvo XC40**: The Volvo XC40 was selected as a representative vehicle with a combined ACC sensor system, utilizing both camera and radar technologies. While cameras are adept at identifying visual cues, such as lane markings and traffic signs, radar excels in measuring the distance and speed of objects. This dual-sensor setup aims to provide a more robust and comprehensive approach to ACC.
* **VW e-Golf**: The VW e-Golf was included in the experiment to showcase a vehicle relying solely on radar-based ACC sensor technology. Choosing the electric VW E-Golf for this experiment not only diversifies the pool of ACC-equipped vehicles but also underscores the adaptability of ACC technology to electric platforms in which different sets of dynamics are presented.  
The utilization of human-driven vehicles in comparison to those above-mentioned vehicles equipped with ACC systems is considered as a focal point of the research. To  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Vehicle** & **Model Year** & **Engine** & **ACC Sensor** & **Length [mm]** & **Source** \\ \hline Subaru Levorg & 2019 & 1.6 L Petrol & Camera & 4690 & Subaru Official Website \\ Volvo XC40 & 2019 & 2.0 L Petrol & Camera-Radar & 4425 & Volvo Official Website \\ VW E-Golf & 2019 & Electric/battery & Radar & 4270 & VW Official Website \\ \hline \hline \end{tabular}
\end{table}
Table 1: Basic information of the tested vehicles.  
conduct a comprehensive analysis, data collection took place across diverse roadways within Gyor City. In this study, the lead vehicle floated through the road network, serving as a data collection platform for observing and recording the behaviors of randomly following vehicles, which are considered to be exclusively human-driven, although distinguishing between purely human-driven vehicles and those equipped with ACC while on the road can be challenging, as modern vehicles often incorporate a variety of ADAS. However, there are certain visual cues and behavioral indicators that may help us make an educated guess. For example, human drivers may exhibit more erratic driving behavior, including sudden accelerations, abrupt lane changes, and less predictable speed variations. In addition, older vehicle models are less likely to be equipped with ACC systems. It is important to emphasize that these indicators are not conclusively definitive. To address this, comprehensive trials were conducted for the case of human driving and meticulously analyzed to attain accurate results and overcome potential uncertainties.