# Efficient Position Change Algorithms for Prolonging Driving Range of a Truck Platoon
## 6 Conclusions and Future Works  
Platooning technology benefits in reducing fuel energy consumption because a cooperative automated driving system with a small inter-vehicle helps the aerodynamic drag effect decrease. Even though the advantages of introduced fuel-saving already prolong the total driving distance of the platoon, we perceive a potential way to improve the driving range to be higher, thus enhancing fuel-saving to be the most efficient. Since vehicles at the front of the platoon will experience more air resistance than the rears, thereby consuming much more energy, vehicles in the platoon should change position from time to time so that each consumes nearly the same amount of fuel. In this paper, we propose two-position change heuristic algorithms to enhance fuel efficiency by balancing fuel consumption in each vehicle to get the highest increased driving range, \"Fuel Amount Heuristic (FAH)\" and \"Traveling Time Heuristic (TTH)\". Furthermore, we also propose an enhancement of the original position change algorithms called \"Sorted Time Slot (STS)\" to decrease the number of position changes, as the higher number of changes, the more possibility of wasting fuel energy in unnecessary position change operations.  
Through our demonstrated simulations, the results show that the proposed algorithm helps to increase the total driving distance significantly. The extended driving range reaches approximately 3% compared to the fixed order platooning in two-truck platooning and accomplishes around 8% increase in six-truck platooning. Therefore, we can conclude that the more vehicles in the platoon, the more driving range increases. Our improved position change algorithm (STS) also results in a reduced number of position changes by ensuring non-duplicated position arrangement along the traveling so that the number of position change counts decreases. We accomplish our purpose for truck platooning technology--to obtain the longest maximum driving distance with a fewer number of position changes, preventing more fuel loss in the process of the position change. In future works, we plan to apply our proposed algorithms to various scenarios and more realistic transportation environments to see whether those algorithms are possible to be implemented with practice-ready truck platooning.  
Conceptualization, S.L; methodology, I.S. and S.L.; software, I.S.; validation, I.S. and S.L.; formal analysis, I.S. and S.L.; investigation, I.S.; resources, I.S.; data curation, I.S.; writing--original draft preparation, I.S.; writing--review and editing, I.S. and S.L.; visualization, I.S. and S.L.; supervision, S.L.; project administration, I.S. and S.L.; funding acquisition, S.L. All authors have read and agreed to the published version of the manuscript.  
This research was supported by Global Scholarship Program for Foreign Graduate Students at Kookmin University in Korea and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2019R1F1A1061136).  
Not applicable.  
The authors declare no conflict of interest.