# Enabling Technologies for Urban Smart Mobility: Recent Trends, Opportunities and Challenges
## 4 Smart Mobility Services and Applications
### Autonomous Vehicles
#### 4.4.4 Ethical Issues  
The recent popularity of autonomous vehicles has drawn the attention of automobile manufacturers from all over the world. Autonomous vehicles represent any means of transportation that are capable of navigating the roads with no or minimum human interventions and provide potential solutions to the road safety issues caused by human errors [93]. The transition from a purely human operated vehicle to a fully automated vehicle is still far from reality. However, many automobile companies are already offering partial automation in terms of services such as emergency brakes application, assisted parking, etc. Despite the several benefits and the rising popularity, the deployment of these vehicles on the road poses several critical challenges related to the operations, technology, legal aspects and, most of all, ethical issues [94]. \begin{table}
\begin{tabular}{c c c} \hline
**Sensor** & **Location** & **Purpose** \\ \hline \hline \multirow{2}{*}{Long-Range Radar} & \multirow{2}{*}{Front-center of the vehicle} & Emergency Braking Pedestrian Detection \\  & & Collision Avoidance \\  & & Adaptative Cruise Control \\ \hline LIDAR & Front, back and 4 corners (diagonals) & Environment mapping \\ \hline \hline \multirow{4}{*}{Camera} & \multirow{4}{*}{Front, back and 2 sides} & Traffic Sign Recognition \\  & & Lane Departure Warning \\ \cline{1-1}  & & Surround View \\ \cline{1-1}  & & Digital Side Mirror \\ \cline{1-1}  & & Rear View Mirror \\ \hline \hline \multirow{2}{*}{Short-Medium Range Radar} & \multirow{2}{*}{Front, back and rear corners} & Cross Traffic Alert \\ \cline{1-1}  & & Rear Collision Warning \\ \hline \end{tabular}
\end{table} 
Table 5: Vehicle sensors, location and its purpose. The main concerns regard how AVs should behave in extreme traffic situations. In the literature, this is known as the trolley problem, first proposed in 1967, where a moral choice must be taken, and the AV should decide whether to kill five people by allowing the trolley to proceed, or kill \"just\" one person while stopping the trolley [95]. This issue has been deeply debated as the Moral Machine Experiment (MME), but there is still no solution. From this research, it emerged that customers are willing to buy AVs that prioritize the safety of their passengers, whilst they agree on others buying AVs that sacrifice passengers' life for a greater good [96]. This is no more a technological problem, but Philosophy, Law and Ethics are involved and the individual good is opposed to a greater one [97]. The trolley problem was the first example of extreme traffic situations that lead to a moral choice. Several situations have been discussed in the literature. Just to mention a few, one regards whether to kill a child or an elderly person to avoid an obstacle, or whether to invade the  
Figure 8: Categories of protocols on vehicular communications. opposite carriageway, thus involving more cars in an accident, to avoid collision with a heavy goods vehicle that surely would strongly injure the AV [98]. From a technical point of view, these choices can be addressed by rules that embed the human driver experience and return risk and gain probabilities. However, first of all, the problem is so complex that it is not possible to foresee all possible situations; moreover, other ethical and moral issues arise: there is the need to judge if the rules are acceptable, then the same rules should be adopted by all the companies, and finally the main issue regards the damage responsibility [98]. It is worth noting that whilst in the scientific literature this moral dilemma has been largely debated, and yet no answers have been found, industry reports on the same topic assume a pragmatic approach. Indeed, these extreme traffic situations are considered to be rare cases that cannot be avoided, and damages to objects and people must be minimized [95]. However, with the spread of the first autonomous vehicles, some accidents have already happened.