METHOD FOR SORTING VEHICLES OF VEHICLE PLATOONS

A method for sorting vehicles of vehicle platoon includes providing a first vehicle platoon driving along a first route and a second vehicle platoon driving along a second route, where the first vehicle platoon has a lead vehicle and a plurality of following vehicles and the second vehicle platoon has a lead vehicle and a plurality of following vehicles. The method selects a road segment in common to the first route and the second route, and controls at least one following vehicle of the first vehicle platoon to leave the first vehicle platoon and join the second vehicle platoon, and/or controls at least one following vehicle of the second vehicle platoon to leave the second vehicle platoon and join the first vehicle platoon, while driving the first vehicle platoon and the second vehicle platoon along said road segment.

TECHNICAL FIELD

The invention relates to a method for sorting vehicles of vehicle platoons and a control arrangement for controlling vehicles of vehicle platoons.

BACKGROUND

In a traffic system comprising vehicle platoons, where each vehicle platoon has a lead vehicle and a plurality of following vehicles driving in a convoy after the lead vehicle, there is a need for individual vehicles to change from one vehicle platoon to another vehicle platoon for reaching the planned destination. The connection and disconnection of vehicles to/from a vehicle platoon should however be performed without disturbances leading to delays and longer driving times.

SUMMARY

An objective of the invention is to provide a method for sorting vehicles of vehicle platoons, by which method connection and disconnection of vehicles to/from a vehicle platoon can be performed in an efficient way.

The objective is achieved by a method for sorting vehicles of vehicle platoons, where the method comprises the steps of providing a first vehicle platoon driving along a first route and a second vehicle platoon driving along a second route, wherein the first vehicle platoon comprises a lead vehicle and a plurality of following vehicles and the second vehicle platoon comprises a lead vehicle and a plurality of following vehicles, and selecting a road segment in common to the first route and the second route, and controlling at least one following vehicle of the first vehicle platoon to leave the first vehicle platoon and join the second vehicle platoon, and/or controlling at least one following vehicle of the second vehicle platoon to leave the second vehicle platoon and join the first vehicle platoon, while driving the first vehicle platoon and the second vehicle platoon along said road segment.

The invention is based on the insight that by such method, vehicles having same planned destination but initially are driving in different vehicle platoons can join the same vehicle platoon while keeping a significant velocity of the vehicle platoons, and then continue towards the planned destination.

According to one embodiment of the method, the method comprises the steps of driving the first vehicle platoon in a first lane of the road segment and driving the second vehicle platoon in a second lane of the road segment, and positioning the first vehicle platoon and the second vehicle platoon relative to each other such that a rear end of the second vehicle platoon is in front of said at least one following vehicle of the first vehicle platoon, controlling said at least one following vehicle of the first vehicle platoon to change from the first lane to the second lane and join the second vehicle platoon at the rear end of the second vehicle platoon, and, the method preferably comprises the steps of repositioning the first vehicle platoon and the second vehicle platoon relative to each other such that a rear end of the first vehicle platoon is in front of said at least one following vehicle of the second vehicle platoon, controlling said at least one following vehicle of the second platoon to change from the second lane to the first lane and join the first vehicle platoon at the rear end of the first vehicle platoon. Hereby, the energy consumption can be kept low at the same time as the sorting of vehicles can be performed in a relatively short time.

According to a further embodiment, the method comprises the steps of performing the lane change of said at least one following vehicle of the first vehicle platoon, and thereafter the lane change of said at least one following vehicle of the second vehicle platoon, during an overtaking where the first vehicle platoon passes the second vehicle platoon. Hereby, no additional braking consuming energy is required for performing sorting of the vehicles.

According to a further embodiment, the method comprises the steps of driving the first vehicle platoon in a first lane of the road segment and driving the second vehicle platoon in a second lane of the road segment, side by side, providing a distance between a first following vehicle and a second following vehicle of the second vehicle platoon, for receiving a following vehicle therebetween at a position corresponding to the longitudinal position of said at least one following vehicle of the first vehicle platoon, controlling said at least one following vehicle of the first vehicle platoon to change from the first lane to the second lane and join the second vehicle platoon between the first following vehicle and the second following vehicle of the second vehicle platoon, and, the method preferably comprises the steps of providing a distance between a first following vehicle and a second following vehicle of the first vehicle platoon, for receiving a following vehicle therebetween at a position corresponding to the longitudinal position of said at least one following vehicle of the second vehicle platoon, controlling said at least one following vehicle of the second vehicle platoon to change from the second lane to the first lane and join the first vehicle platoon between the first following vehicle and the second following vehicle of the first vehicle platoon. Hereby, vehicles can change from one vehicle platoon to any position of another vehicle platoon.

According to a further embodiment, the method comprises the steps of performing the lane change of said at least one following vehicle of the first vehicle platoon and the lane change of said at least one following vehicle of the second vehicle platoon by zipper merging said at least one following vehicle of the first vehicle platoon and said at least one following vehicle of the second vehicle platoon. Hereby, vehicles from two vehicle platoons can be sorted laterally at the same time in an efficient way.

According to another aspect of the invention, a further objective is to provide a control arrangement for controlling vehicles of vehicle platoons, by which control arrangement connection and disconnection of vehicles to/from a vehicle platoon can be performed in an efficient way.

This objective is achieved by a control arrangement for controlling vehicles of vehicle platoons, where the vehicle platoons comprises a first vehicle platoon driving along a first route and a second vehicle platoon driving along a second route, and the first vehicle platoon comprises a lead vehicle and a plurality of following vehicles and the second vehicle platoon comprises a lead vehicle and a plurality of following vehicles, where the control arrangement is configured to select a road segment in common to the first route and the second route, and to control at least one following vehicle of the first vehicle platoon to leave the first vehicle platoon and join the second vehicle platoon, and/or control at least one following vehicle of the second vehicle platoon to leave the second vehicle platoon and join the first vehicle platoon, while the first vehicle platoon and the second vehicle platoon are driving along said road segment.

The advantages of the control arrangement are similar to the advantages already discussed hereinabove with reference to the different embodiments of the method.

DETAILED DESCRIPTION

FIG. 1shows a vehicle platoon1having a lead vehicle2and a plurality of following vehicles3. The lead vehicle2and the following vehicles3are individual vehicles but driven together as a group or convoy. The following vehicles3are positioned in a line after the lead vehicle2. The driving direction is indicated with an arrow8. The lead vehicle2can be a so called autonomous or self-driving vehicle, or the lead vehicle2can be at least partly controlled by an operator of the lead vehicle. The following vehicles3of the vehicle platoon are suitably automatically controlled without any driver assistance.

When driving in the vehicle platoon1, the following vehicles3are controlled to follow the lead vehicle2or the vehicle closest to the front, such that when the speed of the lead vehicle2is increased/decreased the speed of the following vehicles3is increased/decreased correspondingly for maintaining or achieving the desired distances and time gaps between the vehicles. Further, when the lead vehicle2is changing driving direction, a following vehicle3will also change driving direction and follow the lead vehicle or rather the vehicle closest to the front.

For enabling the vehicles2,3to be controlled, each vehicle can be provided with any suitable sensor equipment4for receiving information about the environment, and a control unit5for controlling the vehicle. The sensor equipment gives information about at least the vehicle closest to the front, but preferably the sensor equipment is covering 360 degrees around the vehicle for obtaining the information that is required for longitudinal and lateral control of the vehicle. Such sensor equipment4may comprise LIDAR, radar and ultrasonic sensors, cameras, etc. The information received by the sensor equipment is used by the control unit5for controlling the driving behaviour of the vehicle. In addition, maps, GPS, etc., can be used for determining the current position of a vehicle platoon or an individual vehicle of a vehicle platoon.

Alternatively or in addition to the sensor equipment4, each vehicle2,3is provided with a communication unit6for communicating with one or more of the other vehicles of the vehicle platoon1. Such a communication unit6may comprise any suitable components for establish communication between the vehicles. For example, the communication unit6may comprise a transmitter and a receiver based on radio waves or microwaves. In other words, each vehicle can be part of a local network for communication7between the vehicles of the vehicle platoon1. By means of the local network, control signals can be transmitted from one vehicle to another vehicle. The control signals received are then used by the control unit5arranged on the vehicle for controlling the driving behaviour of the vehicle. Such control signals received by the following vehicles3are preferably at least initially transmitted by the lead vehicle2.

FIG. 2shows two vehicle platoons1a,1bdriving in different lanes of a road. Each vehicle platoon1a,1bof the current traffic system is also part of a central network for communication9between the vehicle platoon1a,1band a central control unit10. By means of the central network, control signals can be transmitted from the central control unit10to a vehicle platoon1a,1bfor controlling the driving behaviour of the vehicle platoon. Such control signals are preferably received by the lead vehicle2a,2bof the vehicle platoon, but could also be received by one or more of the following vehicles3of the vehicle platoon. The central control unit10can be part of a server of a wireless network, such as Internet, for cloud computing.

The central control unit10and the local control unit5arranged on a vehicle may comprise one or more microprocessors and/or one or more memory devices or any other components for executing computer programs to perform the method described hereinafter. Thus, the central control unit and/or the local control unit is preferably provided with a computer program comprising program code means for performing the steps of any example embodiment of the method described hereinafter.

For controlling a vehicle platoon or an individual vehicle of the vehicle platoon when a vehicle is to change from one vehicle platoon to another vehicle platoon, preferably both the control unit5of the vehicle and the central control unit10are used in cooperation.

Alternatively or in addition to what has been described hereinabove, sensors can be arranged in the environment to the current road where the vehicle platoons are driven. These sensors may provide information received by the control unit5and/or the central control unit10. Such sensors could be a complement to the sensors of the vehicles, giving further information and/or redundancy to the system.

FIG. 3is a simplified map showing some routes for vehicle platoons. In this example, a first vehicle platoon is driving from position A to position D along a first route20, and a second vehicle platoon is driving from position B to position C along a second route21. The first route20and the second route21have a road segment22in common. In this case, some following vehicles of the first vehicle platoon could however have position C as final destination, and some following vehicles of the second vehicle platoon could have position D as final destination.

When describing the method hereinafter, reference toFIGS. 1-3will be made.

The method comprises the steps of providing the first vehicle platoon1adriving along the first route20and the second vehicle platoon1bdriving along the second route21. As previously described hereinabove, the first vehicle platoon1acomprises a lead vehicle2aand a plurality of following vehicles3and the second vehicle platoon1bcomprises a lead vehicle2band a plurality of following vehicles3. The method further comprises the steps of selecting the road segment22in common to the first route20and the second route21, and controlling at least one following vehicle3aof the first vehicle platoon1ato leave the first vehicle platoon and join the second vehicle platoon1b, and/or controlling at least one following vehicle3bof the second vehicle platoon1bto leave the second vehicle platoon and join the first vehicle platoon1a, while driving the first vehicle platoon1aand the second vehicle platoon1balong said road segment22.

FIGS. 4A, 4B, 4C and 4Dshow an example embodiment of the method where sorting of vehicles is performed during overtaking. These figures show a part of the road segment22in common to the first route20and the second route21. The road23of the road segment22comprises a first lane24and a second lane25, which lanes preferably are dedicated for vehicle platoons only.

In the example embodiment illustrated inFIGS. 4A-4D, the method comprises the steps of driving the first vehicle platoon1ain the first lane24of the road segment22and driving the second vehicle platoon1bin the second lane25of the road segment22, and positioning the first vehicle platoon1aand the second vehicle platoon1brelative to each other such that a rear end26of the second vehicle platoon1bis in front of said at least one following vehicle3aof the first vehicle platoon1a, and controlling said at least one following vehicle3aof the first vehicle platoon1ato change from the first lane24to the second lane25and join the second vehicle platoon1bat the rear end26of the second vehicle platoon1b.

As indicated inFIGS. 4A and 4B, two following vehicles3a,3a′ of the first vehicle platoon1aare disconnecting from the first vehicle platoon1aand changing from the first lane24to the second lane25for connecting to the second vehicle platoon1b. These following vehicles3a,3a′ are dark grey for illustration purposes only. The wording “connecting” and “disconnecting” to/from a vehicle platoon used herein, is referring to which lead vehicle the following vehicle will follow and the connection to any local network associated with the current vehicle platoon. The vehicles of the vehicle platoon are however individually driven vehicles as previously described hereinabove, though driven together as a group or convoy.

The method further comprises the steps of repositioning the first vehicle platoon1aand the second vehicle platoon1brelative to each other such that a rear end27of the first vehicle platoon1ais in front of said at least one following vehicle3bof the second vehicle platoon1b, controlling said at least one following vehicle3bof the second platoon1bto change from the second lane25to the first lane24and join the first vehicle platoon1aat the rear end27of the first vehicle platoon1a.

As indicated inFIGS. 4C and 4D, two following vehicles3b,3b′ of the second vehicle platoon1bare disconnecting from the second vehicle platoon1band changing from the second lane25to the first lane24for connecting to the first vehicle platoon1a. These following vehicles3b,3b′ are grey for illustration purposes only.

The method can comprise the step of performing the lane change of said at least one following vehicle3aof the first vehicle platoon1a, and thereafter the lane change of said at least one following vehicle3bof the second vehicle platoon1b, during an overtaking where the first vehicle platoon1apasses the second vehicle platoon1b. In the example embodiment illustrated inFIGS. 4A-4D, during the sorting operation of the following vehicles the first vehicle platoon1ahas performed an overtaking relative to the second vehicle platoon1b. After the sorting operation has been performed, the first vehicle platoon1aand the second vehicle platoon1bcan proceed towards their destinations, as indicated inFIG. 4D.

It should be stressed that the sorting operations described herein are preferably performed by controlling the vehicles by means of the equipment and control units described with reference toFIGS. 1 and 2, without any assistance from any driver of any of the vehicles.

FIGS. 5A, 5B, 5C and 5Dshow another example embodiment of the method where sorting of vehicles is performed by zipper merging. These figures show a part of the road segment22in common to the first route20and the second route21. The road23of the road segment22comprises the first lane24and the second lane25, which lanes preferably are dedicated for vehicle platoons only.

In the example embodiment illustrated inFIGS. 5A-5D, the method comprises the steps of driving the first vehicle platoon1ain the first lane24of the road segment22and driving the second vehicle platoon1bin the second lane25of the road segment22, side by side, providing a distance30between a first following vehicle3band a second following vehicle3b′ of the second vehicle platoon1b, for receiving a following vehicle3atherebetween at a position corresponding to the longitudinal position (in the driving direction8) of said at least one following vehicle3aof the first vehicle platoon1a, and controlling said at least one following vehicle3aof the first vehicle platoon1ato change from the first lane24to the second lane25and join the second vehicle platoon1bbetween the first following vehicle3band the second following vehicle3b′ of the second vehicle platoon1b.

As indicated inFIGS. 5A and 5B, two following vehicles3a,3a′ of the first vehicle platoon1aare disconnecting from the first vehicle platoon1aand changing from the first lane24to the second lane25for connecting to the second vehicle platoon1b. These following vehicles3a,3a′ are dark grey for illustration purposes only.

The method can also comprise the steps of providing a distance31between a first following vehicle3and a second following vehicle3aof the first vehicle platoon1a, for receiving a following vehicle3btherebetween at a position corresponding to the longitudinal position (in the driving direction8) of said at least one following vehicle3bof the second vehicle platoon1b, controlling said at least one following vehicle3bof the second vehicle platoon1bto change from the second lane25to the first lane24and join the first vehicle platoon1abetween the first following vehicle3and the second following vehicle3aof the first vehicle platoon1a.

The distances30,31are adapted to the size of the vehicles and the time gap between the vehicles for performing the lane shift.

As also indicated inFIGS. 5A and 5B, two following vehicles3b,3b′ of the second vehicle platoon1bare disconnecting from the second vehicle platoon1band changing from the second lane25to the first lane24for connecting to the first vehicle platoon1a. These following vehicles3b,3b′ are grey for illustration purposes only.

The method can comprise the step of performing the lane change of said at least one following vehicle3aof the first vehicle platoon1aand the lane change of said at least one following vehicle3bof the second vehicle platoon1bby zipper merging said at least one following vehicle3aof the first vehicle platoon1aand said at least one following vehicle3bof the second vehicle platoon1b. In the example embodiment illustrated inFIGS. 5A-5D, during the sorting operation of the following vehicles, two following vehicles3a,3a′ of the first vehicle platoon1aand two following vehicles3b,3b′ of the second platoon1bhave been controlled to perform a zipper merge operation. After the sorting operation has been performed, the first vehicle platoon1aand the second vehicle platoon1bcan proceed side by side towards their destinations, as indicated inFIG. 5D.

The invention also relates a control arrangement40for controlling vehicles of vehicle platoons. When describing the control arrangement40hereinafter, reference is made to previously described figures, particularlyFIGS. 1 and 2.

The control arrangement40preferably comprises one or more of the central control unit10, control units5and communication units6arranged on the vehicles, and the sensor equipment4of the vehicles. For example, the central control unit10is suitably used for selecting the road segment22, and the first vehicle platoon1aand the second vehicle platoon1b, between which vehicle platoons1a,1bone or more following vehicles are to be switched.

In analogy to what is described hereinabove as it regards the method, the control arrangement is configured to control the vehicle platoons1a,1baccordingly.

The control arrangement40is configured to select the road segment22in common to the first route20and the second route21, and to control at least one following vehicle3aof the first vehicle platoon1ato leave the first vehicle platoon1aand join the second vehicle platoon1b, and/or control at least one following vehicle3bof the second vehicle platoon1bto leave the second vehicle platoon1band join the first vehicle platoon1a, while the first vehicle platoon1aand the second vehicle platoon1bare driving along said road segment22.

The control arrangement40can be configured to control the first vehicle platoon1adriving in a first lane24of the road segment22and the second vehicle platoon1bdriving in a second lane25of the road segment22, thereby positioning the first vehicle platoon1aand the second vehicle platoon1brelative to each other such that a rear end26of the second vehicle platoon1bis in front of said at least one following vehicle3aof the first vehicle platoon1a, and to control said at least one following vehicle3aof the first vehicle platoon1ato change from the first lane24to the second lane25and join the second vehicle platoon1bat the rear end26of the second vehicle platoon1b.

Correspondingly, the control arrangement40can be configured to control the first vehicle platoon1aand the second vehicle platoon1bfor repositioning the first vehicle platoon1aand the second vehicle platoon1brelative to each other such that a rear end27of the first vehicle platoon1ais in front of said at least one following vehicle3bof the second vehicle platoon1b, and to control said at least one following vehicle3bof the second vehicle platoon1bto change from the second lane25to the first lane24and join the first vehicle platoon1aat the rear end27of the first vehicle platoon1a.

Further, the control arrangement40can be configured to control the first vehicle platoon1adriving in a first lane24of the road segment22and control the second vehicle platoon1bdriving in a second lane25of the road segment22, and to control a first following vehicle3band a second following vehicle3b′ of the second vehicle platoon1b, thereby providing a distance30between the first following vehicle3band the second following vehicle3b′ of the second vehicle platoon1b, for receiving a following vehicle3atherebetween at a position corresponding to the longitudinal position (in the driving direction8) of said at least one following vehicle3aof the first vehicle platoon1a, and configured to control said at least one following vehicle3aof the first vehicle platoon1ato change from the first lane24to the second lane25and join the second vehicle platoon1bbetween the first following vehicle3band the second following vehicle3b′ of the second vehicle platoon1b.

Correspondingly, the control arrangement40can be configured to control a first following vehicle3and a second following vehicle3aof the first vehicle platoon1a, thereby providing a distance31between the first following vehicle3and the second following vehicle3aof the first vehicle platoon1a, for receiving a following vehicle3btherebetween at a position corresponding to the longitudinal position (in the driving direction8) of said at least one following vehicle3bof the second vehicle platoon1b, and configured to control said at least one following vehicle3bof the second vehicle platoon1bto change from the second lane25to the first lane24and join the first vehicle platoon1abetween the first following vehicle3and the second following vehicle3aof the first vehicle platoon1a.