GB2540039A

GB2540039A - Method for operating a vehicle as a following vehicle in a platoon

Info

Publication number: GB2540039A
Application number: GB1609738.8A
Authority: GB
Inventors: Gabriel Josef; Hudson Walter; Cotter John
Original assignee: Daimler AG
Current assignee: Mercedes Benz Group AG
Priority date: 2016-06-03
Filing date: 2016-06-03
Publication date: 2017-01-04
Also published as: GB201609738D0

Abstract

The invention relates to a method for operating a vehicle 14 as a following vehicle in a platoon 10 which comprises at least one leading vehicle 12 and at least the following vehicle 14 following the leading vehicle 12. The method comprises an optical detection system 22 of the following vehicle 14 detecting at least one pattern (32, Fig.2) arranged on the leading vehicle 12, a receiving system 36 of the following vehicle 14 receiving, with dependence on the detected pattern 32, data broadcasted by the leading vehicle 12 providing characteristics of the state of movement of the leading vehicle 12, and an electronic control unit 40 of the following vehicle 14 adjusting the state of movement of the following vehicle 14 on the basis of the received data. The pattern (32, Fig.2) is preferably used as an identification code for the lead vehicle, and could be designed as a barcode (34, Fig.2).

Description

Method for Operating a Vehicle as a Following Vehicle in a Platoon

The invention relates to a method for operating a vehicle as a following vehicle in a platoon. WO 2013/187835 A1 shows a system for assisting a vehicle behind when overtaking a vehicle train, the vehicle behind and at least a leader vehicle in the train being adapted to communicating via wireless communication. The system comprises a processor unit adapted to receiving from said vehicle behind an overtake signal which indicates that the vehicle behind wishes to overtake the vehicle train. The processor unit is further adapted to receiving from a monitoring system onboard the leader vehicle a monitoring signal which indicates the presence of objects around the leader vehicle which relate to the traffic situation. The processor unit also adapted to analyzing said presence of objects with respect to predetermined criteria related to the possibility of the vehicle behind overtaking safely, and generating an assistance signal which indicates the result of the analysis. The processor unit is further adapted to sending the assistance signal to said vehicle behind, thereby conveying to the driver of the vehicle behind the result of the analysis. The processor unit is also adapted to generating on the basis of said analysis one or more control signals which indicate how one or more of the train’s vehicles need to be regulated to make it possible for said vehicle behind to overtake the train, and sending said one or more control signals to one or more control systems of said vehicles in the train, which vehicle or vehicles are then regulated accordingly.

Furthermore, a system for regulating vehicles in a vehicle train which comprises a leader vehicle and at least one further vehicle adapted to communicating via wireless communication can be found in WO 2013/187834 A1. The system comprises a processor unit which is adapted to: receiving data related to one or more vehicle parameters for a vehicle in the train or in an area around the train; analyzing said data according to predetermined criteria; placing said vehicle in one of a predetermined number of categories based on the result of said analysis, each of which categories has rules for how at least one vehicle in the train is to be regulated on the basis of the categorization; generating at least one control signal which indicates how one or more vehicles in the train are to be regulated on the basis of said categorization; and, sending the control signal to one or more control units on board one or more of the train’s vehicles which are then regulated accordingly.

It is also known that vehicles often drive at different speeds on highways, wherein said vehicles should be organized into caravans or platoons to optimize vehicle energy use and, thus, fuel efficiency as well as safety.

Thus, it is an object of the present invention to provide a method by means of which a particularly efficient and safe operation of a vehicle can be realized.

This object is solved by a method having the features of patent claim 1. Advantageous embodiments with expedient developments of the invention are indicated in the other patent claims.

The invention relates to a method for operating a vehicle as a following vehicle in a platoon which comprises at least one leading vehicle and at least the following vehicle which follows the leading vehicle. The method according to the present invention comprises a first step of, by means of an optical detection system of the following vehicle, detecting at least one pattern arranged on the leading vehicle. For example, said pattern is arranged on a backside of the leading vehicle, in particular on a backside of a trailer of the leading vehicle, wherein the pattern is optically detected by the optical detection system of the following vehicle.

The method according to the present invention further comprises a second step of, by means of a receiving system of the following vehicle, receiving, in dependence on the detected pattern, data broadcasted by the leading vehicle, wherein said data characterize a state of movement of the leading vehicle. For example, the data comprise a cruise set speed, a current speed, an adaptive cruise control availability, a broadcast code, etc. of the leading vehicle.

The method according to the present invention further comprises a third step of, by means of an electronic control unit of the following vehicle, adjusting a state of movement of the following vehicle on the basis of the received data. By means of the method according to the present invention said platoon can be formed in a particularly easy and effective way by operating said vehicle as a following vehicle on the basis of the pattern and the broadcasted data. Thus, the method does not require GPS data (GPS - Global Positioning System) to operate the vehicle as a following vehicle. Thus, GPS data are not required to form the platoon. By forming said platoon and, thus, by operating the vehicle as a following vehicle, a particularly efficient and safe operation of the vehicle can be realized. Driving distances between the leading vehicle and the following vehicle can be kept particularly low which in turn leads to increased fuel economy. Moreover, the method according to the present invention does not require handshaking between the two vehicles to work so that the method can be realized in a particularly easy and cost-effective way. Moreover, preferably, the pattern can be moved from vehicle to vehicle, in particular from trailer to trailer so that different vehicles can be used as leading vehicle particularly easily.

Since, in the method according to the present invention, the state of movement of the following vehicle, in particular the speed of the following vehicle is adjusted on the basis of the data broadcasted by the leading vehicle, the following vehicle’s braking reaction can be kept particularly low thereby ensuring a particularly safe operation. Furthermore, predictive cruise control could be shared among the vehicles thereby realizing a particularly high fuel economy. The method according to the present invention further allows vehicles to join and leave convoys or platoons individually without using GPS data.

Further advantages, features, and details of the invention derive from the following description of a preferred embodiment as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respectively indicated combination but also in other combination or taken alone without leaving the scope of the invention.

The drawings show in:

Fig. 1 part of a schematic side view of a platoon comprising a first vehicle being a leading vehicle, and a second vehicle which is operated as a following vehicle which follows the leading vehicle;

Fig. 2 a schematic back view of the leading vehicle;

Fig. 3 a schematic top view of the vehicles;

Fig. 4 a schematic top view of said vehicles;

Fig. 5 a schematic top view of the platoon; and

Fig. 6 a further schematic top view of the platoon.

In the figures the same elements or elements having the same functions are indicated by the same reference signs.

Fig. 1 shows in a schematic side view a platoon 10 comprising a first vehicle 12 being a leading vehicle of the platoon 10. The platoon 10 further comprises a second vehicle 14 which is a following vehicle of the platoon 10, the following vehicle following the leading vehicle in the platoon 10. The first vehicle 12 is a combination of vehicles, said combination comprising a trailer 16 and a tractor 17 (Fig. 3) to which the trailer 16 is articulated so that the trailer 16 can be moved, in particular pushed and/or pulled by the tractor. Said tractor is a motor vehicle such as a commercial vehicle, in particular a truck. Moreover, the second vehicle 14 is also a combination of vehicles, said combination comprises a second trailer 18 and a second tractor 20 which is a motor vehicle in a form of a commercial vehicle such as a truck.

The trailer 18 is articulated to the tractor 20 so that the trailer 18 can be moved, in particular pulled and/or pushed by the tractor 20. Thus, both vehicles 12 and 14 are configured as long-haul vehicles, wherein the vehicle 12 is a long-haul leading vehicle, and the vehicle 14 is a long-haul following vehicle. Flowever, the method can be used for other types of vehicles. In the following, a method for operating the second vehicle 14 as a following vehicle in the platoon 10 is described. As can be seen from Fig. 1, the second vehicle 14 comprises an optical detection system 22 which comprises at least one camera 24 for visual or optical tracking. The camera 42 has a field of view 26 which is also referred to as fov, wherein the camera 24 can optically detect objects which are arranged in the field of view 26.

Fig. 2 shows the vehicle 12 from the back so that a backside 28 of the trailer 16 can be seen in Fig. 2, the backside 28 facing towards the vehicle 14, in particular the tractor 20. As can be seen from Fig. 2, a pattern element 30 comprising a pattern 32 is attached to the backside 28, the pattern 32 facing towards the vehicle 14, in particular the tractor 20. When the pattern 32 is in the field of view 26 of the camera 24, the pattern 32 can be optically detected by the camera 24 and, thus, the optical detection system 22. As will be described in more detail in the following, the method utilizes the optical detection system 22 configured as a camera tracking system to track objects in the camera’s 24 field of view 26 in front of the vehicle 14 for example, the pattern 32 comprises at least one bar code 34, wherein, for example, the pattern element 30 is configured as a large bar-coded magnet which, for example, is magnetically attached to the backside 28.

The bar-coded magnet (pattern element 30) serves at least two purposes: a first one of said purposes is that the bar-coded magnet has a specific size. The bar-coded magnet’s size is a constant for the optical detection system 22 which is a visual tracking system. The visual tracking system would have a specific object to track versus calculating an object the vehicle 14 is following. A second one of said purposes is to relay a broadcasting code or broadcast of data broadcasted by the leading vehicle 12.

For example, each vehicle 12, 14 continually broadcasts data characterizing a respective state of movement of the respective vehicle 12, 14. This means that at least the leading vehicle 12 broadcasts data characterizing a state of movement of the leading vehicle 12. For example, the broadcasted data comprise a cruise set speed, a current speed, an adaptive cruise control availability, said broadcast code, etc. Said broadcast code is indicative of the data broadcasted by the respective vehicle 12, 14. This means the broadcast code is an identity of the respective data so that, for example, when the leading vehicle 12 broadcasts a first set of data and the second vehicle 14 broadcasts a second set of data, the respective set of data can be identified on the basis of the respective broadcast code belonging to the respective set of data. This means, if a third vehicle received both sets of data, the third vehicle would be able to distinguish the first set of data from the second set of data by means of the broadcast codes. Moreover, said data can also comprise predictive cruise control states so that, in essence, allowing the following vehicle 14 to also benefit from predictive cruise control. As can be seen from the figures, the method is described on the basis of the platoon 10 comprising the two vehicles 12 and 14 only. The method can also be used for platoons comprising n daisy chained vehicles.

In a first step of the method the pattern 32 of the pattern element 30 arranged on the leading vehicle 12 is detected by the means of the optical detection system 22 of the following vehicle 14. In a second step of the method the data broadcasted by the leading vehicle 12 is received in dependence on the detected pattern 32 by means of a receiving system 36 of the following vehicle 14. The receiving system 36 comprises at least one antenna 38 configured to broadcast said data and to receive said data broadcasted by other vehicles such as the leading vehicle 12. Since the pattern 32 is optically detected by the camera 24, an electronic control unit 40 of the following vehicle 14 can determine whether or not the received data are broadcasted by the leading vehicle 12 whose pattern 32 is detected by the camera 24. In order to determine whether or not the received data is broadcasted by the same vehicle whose pattern is detected by the camera 24, said broadcast code is used.

For example, the broadcast code of the broadcasted data is compared with the detected pattern 32. For example, the detected pattern 32 is analyzed by the electronic control unit 40 so as to determine an identification code being indicative of the data broadcasted by the leading vehicle 12. This means, for example, the identification code is encoded in the pattern 32, wherein the pattern 32 is decoded by the electronic control unit 40 in such a way that the identification code contained in the pattern 32 is encrypted. Then, the encrypted identification code is compared with the broadcast code belonging to the received data. If the broadcast code matches the identification code the electronic control unit 40 determines that the received data is broadcasted by the same vehicle whose pattern 32 is detected. Thus, in the present case, the identification code matches the broadcast code since the pattern 32 of the leading vehicle 12 is optically detected by the camera 24 and the data broadcasted by the leading vehicle 12 is received by the receiving system 36 of the following vehicle 14.

In a third step of said method a state of movement of the following vehicle 14 is adjusted on the basis of the received data by means of the electronic control unit 40 of the following vehicle 14. For example, a current speed of the following vehicle 14 is adjusted or set by the electronic control unit 40 on the basis of the received data which are broadcasted by the leading vehicle 12 and received by the following vehicle 14 on the basis of the pattern 32. Since the pattern element 30 is magnetically attached to the trailer 16, the pattern element 30 and, thus, the pattern 32 can be transferred from vehicle to vehicle so that these vehicles can be used as leading vehicles in a platoon.

Fig. 3 shows a traffic situation in which the first vehicle 12 is travelling on a right lane 42 and the second vehicle 14 is travelling on a left lane 44 so that the pattern 32 is not in the field of view 26. Thus, there is no target that could be detected by the camera 24 and used to operate the vehicle 14 as a following vehicle. In the situation shown in Fig. 3, the forward vehicle 12 is broadcasting said broadcast code and said data. However, the bar-coded magnet is not in the proper field of view 26 of the camera 24. Thus, for example, the broadcast code of the data broadcasted by the vehicle 12 is not accepted so that the vehicle 14 is not operated as a following vehicle, i.e. the vehicle 14 is not latched onto the vehicle 12. The following vehicle is also referred to as a trailing vehicle.

Fig. 4 shows a situation in which both vehicles 12 and 14 are travelling in the right lane 42. In the situation shown in Fig. 4, the vehicle 14 is not yet operated as a following vehicle since the identification code first needs to be checked against the broadcast code after acquiring and optically detecting the pattern 32 as a target by means of the camera 24. This means the process of operating the vehicle 14 as a following vehicle starts in the situation shown in Fig. 4. The vehicle 14, in particular the optical detection system 22, begins the process of tracking the vehicle 12, in particular the trailer 16. Now, the bar-coded magnet and, thus, the pattern 32 is in the proper field of view 26 of the visual tracking system, i.e. the camera 24. The bar-coded magnet is read by the visual tracking system of the vehicle 14, wherein the visual tracking system, in particular the electronic control unit 40 relays the bar code 34 or the identification code to the vehicle’s 12 broadcast code thereby comparing the bar code 34 or the identification code with the broadcast code. Moreover, the receiving system 36 begins to receive the data broadcasted by the vehicle 12. The electronic control unit 40 then begins to check the broadcasted vehicle speed of the vehicle 12 versus the speed of the bar-coded magnet. wherein said speed of the bar-coded magnet is, for example, calculated by the electronic control unit 40 on the basis of the optically detected pattern 32. The vehicle speed of the vehicle 12 and the speed of the bar-coded magnet are checked over a predetermined or predeterminable time period. If the calculated speed of the bar-coded magnet and the broadcasted vehicle speed of the vehicle 12 match, the following vehicle 14 will latch onto the vehicle 12, i.e. the vehicle 14 will be operated as a following vehicle in the platoon 10. The broadcasted vehicle speed is a current speed of the vehicle 12, wherein said current speed of the vehicle 12 is characterized by or contained in the data broadcasted by the vehicle 12 and received by the vehicle 14.

Fig. 5 shows a further situation in which the vehicle 14 is latched onto the vehicle 12. This means the vehicle 14 is operated as a following vehicle in the platoon 10, the following vehicle following the leading vehicle. Once latched, the visual tracking system can use the same industry interface for adaptive cruise control which does not preclude using other interfaces and/or a proprietary interface.

Fig. 6 illustrates a situation in which the leading vehicle 12 broadcasts, via said data, an external braking request xbr. This external braking request xbr is, for example, sent by a collision mitigation system of the leading vehicle 12. The xbr is transmitted over the broadcasted data to the following vehicle 14 which, by receiving the broadcasted data, receives the xbr. For example, the electronic control unit 40 of the following vehicle 14 relays the xbr to a brake system of the following vehicle 14, so that, on the basis of the xbr broadcasted by the leading vehicle 12, said brake system of the following vehicle 14 is actuated thereby decelerating the following vehicle 14. This means the following vehicle’s 14 brake system brake system reacts to the external braking request xbr.

Summing up, in the method the vehicle 14, in particular its optical detection system 22 acquires a target vehicle in the form of the leading vehicle 12 by moving behind the target vehicle. The optical detection system 22 uses the bar-coded magnet, in particular its pattern 32 as a reference point to determine whether or not the vehicle 14 is directly behind the target vehicle. The pattern 32 will be read and compared to different data broadcasted by, for example, different vehicles and received by the vehicle 14.

Comparing the pattern 32 to the different data broadcasted by different vehicles and received by the vehicle 14 is to be understood as comparing said identification code contained in the pattern 32 with the respective broadcast codes belonging to the respective data. Once a received broadcast code matches the pattern 32, i.e. the identification code, the visual tracking system, in particular the electronic control unit 40 compares the calculated speed of the detected pattern 32 to the broadcasted and received data whose broadcast code matches the identification code. For example, in said comparison, the calculated speed of the pattern 32 is compared with a speed of the leading vehicle 12, wherein said speed of the leading vehicle 12 is contained in or characterized by the broadcasted and received data whose broadcast code matches the identification code, i.e. the pattern 32. The visual checks against the broadcasted and received data will continue as a safety check so as to ensure the received data are broadcasted by the same vehicle whose pattern 32 is detected by the optical detection system 22. Then, the following vehicle 14 can now be considered locked or latched onto the target vehicle 12. Thus, a distance between the vehicles 12 and 14 can be kept particularly low thereby realizing a particularly efficient operation of the vehicles 12 and 14.

List of reference signs 10 platoon 12 first vehicle 14 second vehicle 16 trailer 17 tractor 18 trailer 20 tractor 22 optical detection system 24 camera 26 field of view 28 backside 30 pattern element 32 pattern 34 bar code 36 receiving system 38 antenna 40 electronic control unit 42 white lane 44 left lane

Claims

1. A method for operating a vehicle (14) as a following vehicle (14) in a platoon (10) which comprises at least one leading vehicle (12) and at least the following vehicle (14) following the leading vehicle (12), the method comprising: by means of an optical detection system (22) of the following vehicle (14): detecting at least one pattern (32) arranged on the leading vehicle (12); by means of a receiving system (36) of the following vehicle (14): receiving, in dependence on the detected pattern (32), data broadcasted by the leading vehicle (12), the data characterizing a state of movement of the leading vehicle (12); by means of an electronic control unit (40) of the following vehicle (14): adjusting a state of movement of the following vehicle (14) on the basis of the received data.

2. The method according to claim 1, wherein, by means of the electronic control unit (40), the pattern (32) is analyzed so as to determine an identification code being indicative of the data broadcasted by the leading vehicle (12), wherein the data are received on the basis of the determined identification code.

3. The method according to claim 1 or 2, wherein, by means of the electronic control unit (40), a speed of the leading vehicle (12) is determined on the basis of the detected pattern (32), wherein the vehicle (14) is operated as the following vehicle (14) in dependence on the determined speed.

4. The method according to any one of the preceding claims, wherein the pattern (32) comprises a bar code (34).