# Road Infrastructure Challenges Faced by Automated Driving: A Review
## 5 Discussion  
In the previous section, we derived five challenges that should be overcome to deal with future mobility. To summarise:  
* Harmonisation: It is a long-term process that involves local road authorities, vehicle manufacturers and legislative bodies as a managing organisation. Harmonisation should aim to accept a common interpretation of the existing standards (MUTCD or Vienna Convention) and upcoming format and standards for digitalisation on the basis of large landmasses. The subject of harmonisation could be parameters that are easily distinguishable among different cultures such as shape, colour and fonts while textual and collocated signs could be solved through digitalisation. Nonharmonised road marking and signs among countries increases the complexity in technology design and acceptance of upcoming ADAS. * Maintenance: In recent years, many reports were written on recommendations for the maintenance and visibility of road markings and traffic signs. AVs will require stricter rules for maintenance, but digitalisation allows potential improvements in real-time road monitoring and maintenance period scheduling. These real-time updates will require access to data from public and private transport, which is part of data access regulation. Moreover, to keep a high level of maintenance and cope with oncoming technology, the road authorities will need to reform their finances and expertise. Yet, there may be a need for clear and precise guidance and policies to support the activities of road authorities. * Design: Through literature research, it was observed that some limitations of ADAS are caused by the design and placement of traffic signs and road markings, which do not normally cause issues for human drivers. Some of those limitations are solvable with sensor fusion, digitalisation or through new regulation. The solutions to issues that are easily solvable and have viable solutions could be addressed in the next maintenance period, while others such as changing the appearance of lines from dashed to solid are not viable at least while human drivers are present. However, those particular issues are solvable through digitalisation. * Digitalisation: Digitalisation is an important and promising step with the potential to increase reliability and support environmental, maintenance and design limitations. However, it is also dependent on strict maintenance and real-time updates. To take full advantage of digitalisation, data access should first be regulated and standardised. Nevertheless, security must remain up-to-date with the progress of digitalisation and sufficiently resist or at least recognise cyber-attacks. * Interdisciplinarity: The need for people with strong skills in multiple fields, such as mechanical engineering, electrical engineering, computer science, traffic sciences and even psychology and biotechnology, is already a necessity, and be increasing required in the future. To cope with this, universities and research activities are already nurture multidisciplinary. This is also of great importance for road authorities that will need to strengthen their collaboration with research, vehicle manufacturers and telecommunication in addition to establishing new job opportunities and extending their in-house expertise. We can observe strong links and integrity over the challenges that are defined through this study. We have noted that digitalisation solves many existing problems not just in improving the reliability of ADS but also in supporting maintenance through real-time road monitoring via public and private transportation. To enable successful data exchange among road authorities, vehicle manufacturers, digital map providers and other stakeholders, a common consensus about data format and standards should be achieved, which should also undergo harmonisation to allow normal traffic flow across the regions of different road jurisdictions. The same implementation of standards as in MUTCD or Vienna Convention would simplify the process of digitalisation and the market penetration of ADS.