While commercial trucking is a promising early implementation area for autonomy, it will still take at least till the end of the decade before autonomous trucks are widespread on public roads. Issues relating to safety, security, privacy, and liability still remain, which manifest as legal and policy issues. As a result, some level of driver supervision would likely still be needed in initial deployments. This would also circumvent regulatory barriers around the absence of a driver and allow going to market quicker.
With cruise control and lane-keeping assist already commercially available, further progress in the area points to platooning as a next step. Simply put, a platoon is a set of virtually connected trucks that drive behind one another at short headways. However, even within platooning, the level of driver involvement can vary. It is highly likely that the level will decrease as technology and regulations evolve, leading to different forms of platooning, each with its own characteristics and challenges. Like autonomous trucking, platooning will affect the system it operates in. However, the exact nature of the effect depends on the form of platooning and understanding these is important to the successful deployment of not just platooning but also autonomous trucking. Here, we outline the different forms of platooning and explain their likely roles in the real world.
All drivers in a platoon are required to be attentive at all times. The drivers in the following trucks receive assistance in operational tasks like braking and/or steering but would still be in control of tactical tasks like changing lanes and making turns. Since drivers need to be present and attentive, the cost savings from human-driven platooning stem solely from the fuel savings, which range from 6% to 10% depending on surrounding conditions.
Human-driven platooning with in-platoon resting
In this type of platooning, the following trucks can handle all the driving tasks, which means that drivers in the following trucks may rest while in platoon. This can allow for more efficient utilization of the drivers. This comes from the trucks in such a platoon still being able to drive without needing to stop to adhere to driver resting time regulations. These regulations vary by region and depend on the type of vehicle. For instance, drivers in the EU need to take a 45-minute break after driving for a period of 4.5 hours, while drivers in the U.S. must take a 30-minute break after driving for eight hours. Trucks in such a platoon can take turns being the leader, allowing the drivers in the following trucks to take breaks while still continuing toward their destination(s). In addition to resting, drivers in the following trucks may engage in other nondriving tasks.
For widespread deployment, this would require technological feasibility and legal clearance, which are both still quite a way off. However, since humans are still involved, regulations will plausibly allow for widespread deployment of such platoons much earlier than of autonomous trucks. Another important consideration here is driver resistance toward having to stay in their trucks even during breaks. Regulations around this will likely need to be updated.
Locomation is pursuing this form of platooning to get to market more quickly.
This type of platooning allows the removal of drivers from one or all of the following trucks in a platoon. Drivers would still need to be present when a truck is outside the platoon. Because fewer drivers are needed, hybrid platooning has great potential to reduce overall costs. However, it does lead to logistical challenges similar to those associated with fully autonomous trucks. For instance, drivers usually assist with tasks like (un)loading trucks, and with a single driver driving multiple trucks, a company might need to allocate more labor to these associated tasks.
When trucks that don't share origins (or destinations) need to meet (or split up) en route to form a platoon, hybrid platooning can offer great flexibility but at the same time become complicated to plan and operate. Since the trucks would still need drivers for the first and last part of their trips when they are driving alone, the formation or dissolution of platoons would require dedicated locations and can no longer be done en route. Drivers would then have to be moved around these points based on truck movements. Drivers could also switch roles at these points. For instance, a driver dropped off at such a point could take over a platoon with the original platoon driver then completing the last mile of a decoupled truck. Planning such an operation would require a high degree of collaboration and is very complex.
As the name states, these are platoons with drivers in none of the trucks. While the first three forms of platooning could be seen as steps toward fully autonomous trucking, this one is more a consequence of autonomous trucking and will occur only after autonomous trucking has been deployed widely, at least on certain corridors. That is, when many trucks on the road can drive fully autonomously, they may as well automatically form platoons to reduce fuel consumption.
With driver involvement gradually diminishing in platooning, it can be seen as a sequential pathway toward fully autonomous trucking. However, in practice, we are likely to see these forms deployed only in limited settings, i.e., each of these forms is unlikely to reach widespread deployment on its own.
Human-driven platooning offers savings only in the form of reduced fuel consumption and is therefore likely to be restricted to testing. Companies will use this form to fine-tune their technology and aim for deployment of one of the more advanced forms where labor cost savings enter the picture. Human-driven platooning with in-platoon resting will most likely be the form of platooning that sees the most deployment compared with the others. It offers more benefits but also does not affect logistics operations as heavily as hybrid platooning might. Since hybrid platooning could also lead to a lot of planning and operational complexities, it probably will be restricted to fixed routes; for instance, something like a middle-mile route where trucks constantly drive between the same locations. Driverless platooning, as indicated, is a final step and a consequence of fully autonomous trucking.