SE538767C2

SE538767C2 - Method and control unit for determining a velocity profile for each vehicle comprised in a platoon of grouped vehicles

Info

Publication number: SE538767C2
Application number: SE1550385A
Authority: SE
Inventors: Johansson Björn; Flärdh Oscar
Original assignee: Scania Cv Ab
Priority date: 2015-03-31
Filing date: 2015-03-31
Publication date: 2016-11-15
Also published as: DE102016003433A1; SE1550385A1

Description

25 30 35 538 767 Thereby, the optimal driving methodology, perhaps in particular when driving in hilly terrain, may be different for different vehicles. ln case the first vehicle in the platoon is an unloaded vehicle, it may hardly be affected at all by the uphill, while a heavily loaded following vehicle may not be able to maintain the desired speed.

Another and perhaps even bigger problem in particular for platoons comprising a large number of vehicles driving in hilly terrain is that the vehicles are in different states of incli- nation in all times, except when the road is horizontal.

For example, in case of uphill driving followed by a downhill, a single vehicle is normally releasing the accelerator when approaching the hill peak in order to roll over the peak and downhill without any driving torque in the powertrain of the vehicle. Thereby fuel is saved.

However, when a platoon is driving in the same hilly environment (uphill followed by down- hill) and the first vehicle of the platoon is approaching the hill peak, the following vehicles are still driving uphill and need to increase the engine torque in order to overcome the hill. ln case the first vehicle of the platoon release the accelerator when approaching the hill peak, the following vehicles will have to brake away energy in order to keep the distance to the forward vehicle. A following vehicle in the platoon which may be in the beginning of the uphill, may after the brake be required to change gears, leading to further lost velocity dur- ing the time of the gear change. The vehicle then has to speed up for reducing the gap to the forward vehicle, causing also the behind vehicle to speed up etc. Such inconsequent braking and acceleration will increase the fuel consumption of the vehicles in the platoon substantially.

The reversed problem may appear in the opposite situation when the first vehicle in the platoon starts driving downhill and increase speed due to gravity while the following vehicle may be driving on plain ground, or uphill and thus the following vehicle has to accelerate in order to keep the time gap, just for start braking some seconds later.

Thereby energy is unnecessarily wasted. Also, the brakes are excessively used, which may lead to early replacement due to wear, i.e. increased maintenance costs. lt also pre- sents a potential security problem, if a vehicle should run out of brake capacity when driv- ing in a platoon. 10 15 20 25 30 35 538 767 Thus, previously known look-ahead control strategies for a single vehicle in order to reduce fuel consumption are not necessarily suitable for platoons.

There are studies indicating that platoon driving is more fuel consuming in hilly terrain than normal driving. The above described problems are true for any kind of vehicles, but the effects will increase with vehicle weight, as more energy is required for accelerating a heavy vehicle like a truck or bus in comparison with a car.

As these described scenarios, and similar variants of them, will lead to increased fuel con- sumption, it is desirable to find a solution in order to achieve the advantages of platoon driving.

SUMMARY lt is therefore an object of this invention to solve at least some of the above problems and improve platooning.

According to a first aspect of the invention, this objective is achieved by a method for de- termining a velocity profile for each vehicle comprised in a platoon of grouped vehicles, for use in an upcoming road section, situated ahead of the platoon in the driving direction. The method comprises obtaining at least two candidate velocity profiles for the platoon to keep at the upcoming road section from at least two of the vehicles in the platoon. Also, the method comprises distributing the obtained candidate velocity profiles to the at least two vehicles in the platoon. Further, the method also comprises evaluating each distributed candidate velocity profile at the at least two vehicles, based on how preferable the respec- tive candidate velocity profile would be for the own vehicle in order to reduce a weighted sum of energy consumption and travel time of said vehicle with regard to the topology of the upcoming road section. Furthermore, the method in addition comprises compiling the made evaluations of each distributed candidate velocity profile, made by the at least two vehicles. The method also comprises determining the velocity profile for each vehicle in the platoon, to be used when driving at the upcoming road section, based on the compiled evaluations of the distributed candidate velocity profiles.

According to a second aspect of the invention, this objective is achieved by a control unit for determining a velocity profile for each vehicle comprised in a platoon of grouped vehi- cles, for use in an upcoming road section, situated ahead of the platoon in the driving direc- tion. The control unit is configured for obtaining at least two candidate velocity profiles for the platoon to keep at the upcoming road section from at least two of the vehicles in the 10 15 20 25 30 35 538 767 platoon. Also, the control unit is configured for distributing the obtained candidate velocity profiles to the at least two vehicles grouped in the platoon. Additionally, the control unit is configured for evaluating each distributed candidate velocity profile at the at least two vehi- cles, based on how preferable the respective candidate velocity profile would be for the own vehicle in order to reduce a weighted sum of energy consumption and travel time of said vehicle with regard to the topology of the upcoming road section. Furthermore, the control unit is configured for compiling the made evaluations of each distributed candidate velocity profile, made by the at least two vehicles. Also, the control unit is configured for determining the velocity profile for each vehicle in the platoon, to be used when driving on the upcoming road section, based on the compiled evaluation of the distributed candidate velocity profiles.

Thanks to the described aspects, platooning may be made energy saving also in hilly ter- rain, as unnecessary braking and acceleration respectively is avoided. Thereby energy consumption of the platoon as a whole is reduced, while maintaining a safe distance be- tween the vehicles in the platoon. Furthermore, the disclosed aspects enable justice be- tween the vehicles, for distributing the advantages of the energy savings between the vehi- cles. Also, thanks to the described aspects, no vehicle has to expose or reveal any proprie- tary or sensitive information concerning the performance of the vehicle and drivetrain. Fur- thermore, the described aspects are robust and easily understandable, thereby presenting an easily implemented solution to energy saving platooning.

Other advantages and additional novel features will become apparent from the subsequent detailed description.

FIGURES Embodiments of the invention will now be described in further detail with reference to the accompanying figures, in which: Figure1 illustrates a vehicle organised in a platoon according to an embodiment of the invention; Figure 2A illustrates a vehicle according to an embodiment of the invention; Figure 2B illustrates a platoon according to an embodiment of the invention; Figure 2C illustrates a first vehicle in a platoon according to an embodiment of the in- vention; Figure 2D illustrates a first vehicle in a platoon according to an embodiment of the in- vention; 10 15 20 25 30 35 538 767 Figure 2E illustrates a first vehicle in a platoon according to an embodiment of the in- vention; Figure 3A illustrates a vehicle in a platoon according to an embodiment of the inven- tion; Figure 3B illustrates a vehicle in a platoon according to an embodiment of the inven- tion; Figure 4 is a flow chart illustrating an embodiment of the method; Figure 5 is an illustration depicting a system according to an embodiment.

DETAILED DESCRIPTION Embodiments of the invention described herein are defined as a method and a control unit, which may be put into practice in the embodiments described below. These embodiments may, however, be exemplified and realised in many different forms and are not to be lim- ited to the examples set forth herein; rather, these illustrative examples of embodiments are provided so that this disclosure will be thorough and complete.

Still other objects and features may become apparent from the following detailed descrip- tion, considered in conjunction with the accompanying drawings. lt is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the herein disclosed embodiments, for which reference is to be made to the appended claims. Further, the drawings are not necessarily drawn to scale and, unless othen/vise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Figure 1 illustrates a scenario with a multitude of vehicles 100-1, 100-2, 100-3, driving in a driving direction 105, with an inter-vehicular distance t1, t2, organised in a platoon 110, driving on a road 120.

The vehicle platoon may be described as a chain of coordinated, inter-communicating ve- hicles 100-1, 100-2, 100-3 travelling at given inter-vehicular distances t1, t2 and velocity.

The inter-vehicular distances t1, t2 may be fixed or variable in different embodiments. Fur- ther, the inter-vehicular distances t1, t2 may comprise a time gap, or a length distance in different embodiments. Also, the inter-vehicular distances t1, t2 may be identical between some or all of the vehicles 100-1, 100-2, 100-3 in the platoon 110 in some embodiments.

Alternatively however, the inter-vehicular distances t1, t2 between each of the vehicles 10 15 20 25 30 35 538 767 100-1, 100-2, 100-3 in the platoon 110 may be distinct. Further, the inter-vehicular distanc- es t1, t2 in length between any vehicles 100-1, 100-2, 100-3 in the platoon 110 may vary with the speed of the vehicles 100-1, 100-2, 100-3, as the time gaps t1, t2 will create length distances of different length in different vehicle speeds (except when driving at very low speed, approaching a stationary condition, where a certain minimum distance in length may be desired). Thus the distances t1, t2 may be e.g. some centimetres, some decime- tres, some meters or some tenths of meters in some embodiments, such as e.g. 20-40 meters. ln other embodiments, the distances t1, t2 may be e.g. some fractions of a second such as e.g. some tenths of a second. The inter-vehicular distances t1, t2 may be the same between at least some of the vehicles 100-1, 100-2, 100-3 in the platoon 110 in some em- bodiments. Alternatively, each vehicle 100-1, 100-2, 100-3 in the platoon 110 may have a different distance t1, t2 to the vehicle following or leading vehicle 100-1, 100-2, 100-3, than all other vehicles 100-1, 100-2, 100-3 in the platoon 110.

The low inter-vehicular distances t1, t2 in the platoon 110, in comparison with the normal distance kept between non-coordinated vehicles, leads to reduced air drag for the vehicles 100-1, 100-2, 100-3 in the platoon 110, leading to reduced energy consumption.

The distance to the preceding vehicle 100-1, 100-2, 100-3 may be measured by a e.g. ra- dar unit, lidar unit or similar equipment in some embodiments, configured for emitting radio waves and receiving reflexions of the emitted radio waves, reflected by the preceding vehi- cle 100-1, 100-2, 100-3. By continuously or at certain time intervals measuring the distance to the preceding vehicle 100-1, 100-2, 100-3 and also continuously or at certain time inter- vals determine the speed of the vehicle 100-1, 100-2, 100-3, e.g. from the speedometer of the vehicle 100-1, 100-2, 100-3, or from a Global Positioning System (GPS) receiver in the vehicle 100-1, 100-2, 100-3. Thereby, the time gaps t1, t2 may be calculated by dividing the measured distance in length with the determined speed.

According to some alternative embodiments, another on-board rangefinder sensor may be used instead of the radar unit, such as e.g. a laser rangefinder, an ultrasonic sensor emit- ting an ultrasonic wave and detecting and analysing the reflections, or other similar devic- es. ln order to keep the respective time gap t1, t2 signals may be generated for increasing the speed of the vehicle 100-1, 100-2, 100-3, or braking the vehicle 100-1, 100-2, 100-3, re- spectively. Thereby a safe distance is upheld to the preceding vehicle 100-1, 100-2, 100-3. 10 15 20 25 30 35 538 767 The vehicles 100-1, 100-2, 100-3 in the platoon 110 may comprise e.g. a truck, a bus, a car, a motorcycle or any similar vehicle or other means of conveyance. The vehicles 100-1, 100-2, 100-3 may comprise vehicles of the same, or different types.

The vehicles 100-1, 100-2, 100-3 may be driver controlled or driverless autonomously con- trolled vehicles in different embodiments. However, for enhanced clarity, the vehicles 100- 1, 100-2, 100-3 are subsequently described as having a driver.

According to some embodiments, a velocity profile for each vehicle 100-1, 100-2, 100-3 comprised in a platoon 110 of grouped vehicles 100-1, 100-2, 100-3, to be used at an up- coming road section ahead of the platoon 110. Thus each vehicle 100-1, 100-2, 100-3 in the platoon 110, or at least some of those vehicles 100-1, 100-2, 100-3, may calculate and suggest at least one candidate velocity profile each. These candidate velocity profiles may then be distributed wirelessly to each other vehicle 100-1, 100-2, 100-3 in the platoon 110, e.g. by making a wireless broadcast. Each vehicle 100-1, 100-2, 100-3 may then evaluate the received candidate velocity profiles, based on how appropriate they are for the own vehicle 100-1, 100-2, 100-3, in particular in terms of energy consumption, such as e.g. fuel consumption, with regard to the topology of the ahead road section.

The evaluation may result in a rating or ranking of the received candidate velocity profiles.

In some embodiments, any of the vehicles 100-1, 100-2, 100-3 may prohibit utilisation of a candidate velocity profile that would result in an accident (or that a minimum distance t1, t2 between the vehicles 100-1, 100-2, 100-3 is breached), or that would be impossible to fol- low by the vehicle 100-1, 100-2, 100-3 due to constraints of the vehicle 100-1, 100-2, 100- 3.

The made evaluations or ratings of the respective candidate velocity profiles are then dis- tributed among the vehicle 100-1, 100-2, 100-3 of the platoon 110.

Based on the evaluations of the candidate velocity profiles, candidate velocity profiles to be kept when driving on the upcoming road section may be determined. In some embodi- ments, the candidate velocity profiles with the highest rating may be selected within the candidate velocity profiles. ln other embodiments, an interpolation may be made between the candidate velocity profiles, such as e.g. a weighted interpolation between the candidate velocity profiles. 10 15 20 25 30 35 538 767 Candidate velocity profiles that result in that minimum distances t1, t2 between any vehi- cles 100-1, 100-2, 100-3 in the platoon 110 cannot be kept may be disregarded from the candidate velocity profiles in some embodiments.

Thereby, an appropriate velocity profile for each vehicle 100-1, 100-2, 100-3 comprised in the platoon 110, for the ahead road section is selected and determined, enabling a reduced and/ or low energy consumption for the platoon 110 as a whole. Thereby energy efficient driving may be made by the platoon 110 in all kind of landscapes, including hilly terrain.

Another advantage of the described method is that a particular velocity profile, which is very disadvantageous for a particular vehicle 100-1, 100-2, 100-3 may be disregarded, providing improved fairness between the vehicles 100-1, 100-2, 100-3 in the platoon 110.

Reducing the energy consumption, when the vehicles 100-1, 100-2, 100-3 are using fossil fuel, leads to not only cheaper transport, but also reduced emissions of harmful exhaust gas, such as e.g. carbon dioxide.

Yet another advantage with the described method is that the vehicles 100-1, 100-2, 100-3 in the platoon 110 do not have to share any (potentially sensitive) data or parameters with other vehicles 100-1, 100-2, 100-3 in the platoon 110. The vehicles 100-1, 100-2, 100-3 may belong to different, competitive owners, which are reluctant to share data of their vehi- cles 100-1, 100-2, 100-3 with their competitors.

A further advantage of the described method is that it is robust and easy to understand, making it easier to implement compared to other alternative, more complex methods.

Yet an advantage is the flexibility of the method, which may be implemented in a distribut- ed manner, enabling all vehicles 100-1, 100-2, 100-3 in the platoon 110 to participate in the decision concerning the velocity profile selection for vehicles 100-1, 100-2, 100-3 in the platoon 110, but may also be centralised to one vehicle 100-1, 100-2, 100-3, or vehicle external node.

Figure 2A illustrates an example of a scenario where a single vehicle 100 is driving on the road 120 in the driving direction 105 and has arrived to a hilly region.

The vehicle 100 has been driving uphill, and has reached the hill peak. When the vehicle 100 was approaching the hill peak at a first position 210-1, the driver may release the ac- celerator and roll over the hill peak, firstly with descending velocity, but after having passed 10 15 20 25 30 35 538 767 the hill peak, the vehicle 100 gain velocity in the downhill slope. At a second point 210-2, the driver may again start pressing down the accelerator in order to gain velocity and mo- mentum for overcoming an ahead uphill slope (out of Figure 2A).

This method, which may be optimal from a fuel consumption perspective concerning a sin- gle vehicle 100 is however not appropriate during platooning, as will be further exemplified in Figure 2B.

Figure 2B illustrates the same, or a similar hill as illustrated in Figure 2A, but with a pla- toon 110 comprising various vehicles 100-1, 100-2, 100-3 with a distance t1, t2 in between them, driving in a driving direction 105; i.e. from the right to the left in the Figure 2B.

When the first vehicle 100-1 in the platoon 110 is approaching the hill peak, and from a single vehicle optimisation point of view would benefit from releasing the accelerator in order to roll over the top and roll downhill, thereby saving energy. However, the other fol- lowing vehicles 100-2, 100-3 are still driving uphill and releasing the accelerator is inappro- priate for these vehicles 100-2, 100-3, as they then may not have enough momentum for overcoming the hill.

Another problem is that the different vehicles 100-1, 100-2, 100-3 in the platoon 110 may have different weight and/ or different weight/ power ratio. Thereby, different vehicles 100- 1, 100-2, 100-3 may be affected differently both in downhill and uphill. ln hilly terrain, perhaps in particular for heavy vehicles such as e.g. trucks when travelling along an incline, the gravitational force has a strong influence. ln contrast with a passenger vehicle, heavy vehicles is typically not able to produce a sufficient driving torque to main- tain the velocity when travelling along an uphill with a slope greater than e.g. approximately 3.5% at 90 km/h in a non-limiting example, which further is different for different vehicles 100-l, 100-2, 100-3 based on different properties of the vehicles 100-1, 100-2, 100-3.

Similarly, when facing a downhill heavy vehicles will typically experience a speed increase if the slope is less than e.g. approximately -1.4% or there about in a non-limiting example, which again is merely exemplary and may be very depending on different properties of the vehicles 100-1, 100-2, 100-3 such as weight, engine, etc. Hence, the induced gravitational force can act as a positive or negative longitudinal force depending on the incline of the road 120. 10 15 20 25 30 35 538 767 Different vehicles 100-1, 100-2, 100-3 in the platoon 110 may have different weight and/ or different weight/ power ratio. Thus, in order for the vehicles 100-1, 100-2, 100-3 in the pla- toon 110 to pass the hill in a grouped manner and still earning the advantages with the platoon formation, velocity profiles for the vehicles 100-1, 100-2, 100-3 in the platoon 110 has to be determined, that minimises or at least reduces a weighted sum of energy con- sumption and travel time of the vehicles 100-1, 100-2, 100-3. ln some embodiment, distinct velocity profiles may be used for each vehicle 100-1, 100-2, 100-3 in the platoon 110. On some other embodiments, some or all of the vehicle 100-1, 100-2, 100-3 in the platoon 110 may share the same velocity profile, to keep at the upcoming road segment.

The weighted sum of energy consumption and travel time of the vehicles 100-1, 100-2, 100-3 may be computed for minimising or reducing the energy consumption, while keeping the vehicles 100-1, 100-2, 100-3 in the platoon 110 within a certain velocity range, such as e.g. 70-80 km/h, 80-85 km/h, 80-90 km/h or similar, just for mentioning some non-limiting arbitrary examples. Typically, the velocity of the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be allowed to increase to the upper velocity limit of the velocity range when driv- ing in downhill and be allowed to decrease to the lower velocity limit of the velocity range othen/vise.

Thus some kind of compromise has to be calculated, that minimises or at least reduces the energy consumption of the platoon 110 as a whole. The bigger distance t1, t2 there is be- tween the vehicles 100-1, 100-2, 100-3, the bigger differences there may be between the different velocity profiles for the vehicles 100-1, 100-2, 100-3 in the platoon 110. Thus there may be a relation between the distances t1, t2 between the vehicles 100-1, 100-2, 100-3, and the velocity of the vehicles 100-1, 100-2, 100-3 in some embodiments.

Figure 2C illustrates how the selection of the velocity profiles for the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be made when driving on the road 120 on a current road section 220-1, for determining the velocity profiles to be used in an upcoming road section 220-2. Thereby, the computation and selection of the velocity profiles may be made in tranquillity, and all computations may be ready in advance, before the vehicles 100-1, 100- 2, 100-3 in the platoon 110 reach the upcoming road section 220-2.

Thus, in some embodiments, the way from a starting point to the destination of the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be divided into a plurality of road sections 220- 1, 220-2, for all or parts of the distance. While driving on the current road section 220-1, for determining velocity profiles to be used in an upcoming road section 220-2, and when arriv- 10 10 15 20 25 30 35 538 767 ing to the upcoming road section 220-2, the determining velocity profiles are used by the vehicles 100-1, 100-2, 100-3 in the platoon 110, and computations are then repeated for determining further velocity profiles to be used by the vehicles 100-1, 100-2, 100-3 in the platoon 110 in yet an upcoming road section, etc.

The road slope may be determined at different geographical positions of the road 120 ahead of the platoon 110 in the driving direction 105, such as e.g. at the current road sec- tion 220-1 and the upcoming road section 220-2, and/ or within the upcoming road section 220-2.

The upcoming road section 220-2 may be defined by one of the vehicles 100-1, 100-2, 100-3 in the platoon 110, or they may have been previously agreed upon. ln the illustrated embodiment, the upcoming road section 220-2 starts where the current road section 220-1 ends, i.e. the road sections 220-1, 220-2 are not overlapping each oth- er. However, in other embodiments, as illustrated in Figure 2D, the road sections 220-1, 220-2 may be overlapping each other, partly or entirely. ln embodiments where the road sections 220-1, 220-2 are overlapping each other, the ve- hicle profile/s determined for the upcoming road section 220-2 takes precedence over the determined vehicle profile/s used at the current road section 220-1. ln some embodiments, overlapping of the road sections 220-1, 220-2 may be compulsory.

The road sections 220-1, 220-2 may have different sizes depending e.g. on the topography and may be e.g. at least twice the length of the platoon 110 in some embodiments.

Figure 2E illustrates how the selection of the velocity profile for each of the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be made when driving on the road 120 on a current road section 220-1, for determining the velocity profiles to be used by vehicles 100-1, 100- 2, 100-3 in the platoon 110 in an upcoming road section 220-2. When arriving at the up- coming road section 220-2, the determined velocity profiles may be used by the vehicles 100-1, 100-2, 100-3 in the platoon 110. Further, upon arrival at the upcoming road section 220-2, the method and computations may be repeated for determining velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, to be used at a further upcoming road section 220-3. This is again then repeated when arriving at the further upcoming road sec- tion 220-3 for determining velocity profile/s to be used by the vehicles 100-1, 100-2, 100-3 in the platoon 110 at the subsequently further upcoming road section 220-4, etc. 11 10 15 20 25 30 35 538 767 Thereby, the computation and selection of the velocity profiles may be made in tranquillity, and all computations may be ready in advance, before the vehicles 100-1, 100-2, 100-3 in the platoon 110 reach the upcoming road section 220-2.

Figure 3A illustrates an example of how any of the previously scenario in Figure 1 and Figures 2B-2E may be perceived by the driver of a vehicle 100-1, 100-2, 100-3 in the pla- toon 110. Although the second vehicle 100-2 in the platoon 110 is illustrated, this is merely a non-limiting example. Any other vehicle 100-1, 100-2, 100-3 in the platoon 110, or some or all of them may be equally or similarly equipped.

The vehicle 100-2 thus follow the preceding vehicle 100-1 at a distance t1, t2. The vehicle 100-2 comprises a control unit 310 configured for determining a velocity profile for vehicles 100-1, 100-2, 100-3 in the platoon 110. ln some embodiments, the control unit 310 may comprise, or be part of an Adaptive Cruise Control (ACC).

ACC is an optional cruise control system for vehicles 100-1, 100-2, 100-3 that automatical- ly adjusts the vehicle speed to maintain a safe distance from vehicles 100-1, 100-2, 100-3 ahead. The ACC may utilise e.g. on-board sensors such as a radar or a laser sensor for maintaining the distance t1, t2 to the vehicle 100-1, 100-2, 100-3 in front, or behind, and/ or satellites, roadside beacons or mobile infrastructures as reflectors or transmitters on the back of other vehicles 100-1, 100-2, 100-3 ahead, in different embodiments. ln some embodiments, an optional display 370 may be comprised in the vehicle 100-2, connected to the control unit 310. Thereby, information associated with the velocity profiles and/ or the platoon 110 such as e.g. current size of the distance/ time gap t1, t2, current road slope ahead of the vehicle 100-1, 100-2, 100-3, etc.

The vehicle 100-2 also comprises a vehicle mounted distance measuring device 320, such as e.g. radar unit, a rangefinder sensor, a stereo camera, an ultrasonic sensor emitting an ultrasonic wave and detecting and analysing the reflections or similar device based on ra- dar, infra-red light or micro waves for detecting the vehicle 100-1 in front, and determine the inter vehicular distances t1, t2.

Further, the vehicle 100-2 comprises a positioning unit 330. The positioning unit 330 may be based on a satellite navigation system such as the Navigation Signal Timing and Rang- 12 10 15 20 25 30 35 538 767 ing (Navstar) Global Positioning System (GPS), Differential GPS (DGPS), Galileo, GLONASS, or the like. Thus the positioning unit 330 may comprise a GPS receiver.

The geographical position of the vehicle 100-2 may be determined continuously or at cer- tain predetermined or configurable time intervals according to various embodiments.

Positioning by satellite navigation is based on distance measurement using triangulation from a number of satellites 340-1, 340-2, 340-3, 340-4. The satellites 340-1, 340-2, 340-3, 340-4 continuously transmit information about time and date (for example, in coded form), identity (which satellite 340-1, 340-2, 340-3, 340-4 which broadcasts), status, and where the satellite 340-1, 340-2, 340-3, 340-4 are situated at any given time. GPS satellites 340- 1, 340-2, 340-3, 340-4 sends information encoded with different codes, for example, but not necessarily based on Code Division Multiple Access (CDMA). This allows information from an individual satellite 340-1, 340-2, 340-3, 340-4 distinguished from the others' infor- mation, based on a unique code for each respective satellite 340-1, 340-2, 340-3, 340-4.

This information can then be transmitted to be received by the appropriately adapted posi- tioning unit 330 in the vehicle 100-2.

Distance measurement can according to some embodiments comprise measuring the dif- ference in the time it takes for each respective satellite signal transmitted by the respective satellites 340-1, 340-2, 340-3, 340-4, to reach the positioning unit 330. As the radio signals travel at the speed of light, the distance to the respective satellite 340-1, 340-2, 340-3, 340- 4 may be computed by measuring the signal propagation time.

The positions of the satellites 340-1, 340-2, 340-3, 340-4 are known, as they continuously are monitored by approximately 15-30 ground stations located mainly along and near the earth's equator. Thereby the geographical position, i.e. latitude and longitude, of the vehicle 100-2 may be calculated by determining the distance to at least three satellites 340-1, 340- 2, 340-3, 340-4 through triangulation. For determination of altitude, signals from four satel- lites 340-1, 340-2, 340-3, 340-4 may be used according to some embodiments.

Having determined the geographical position of the vehicle 100-2, and also determined the driving direction 105 of the vehicle 100-2 and the platoon 110, the control unit 310 may extract a road slope at a geographical position of the road 120 ahead of the vehicle 100-2 in the determined driving direction 105, such as e.g. on the upcoming road section 220-2. 13 10 15 20 25 30 35 538 767 The topography i.e. road slope of the upcoming road section 220-2 ahead of the vehicle 100-2 may be extracted from a database 350. The database 350 may be situated within the vehicle 100-2 in some embodiments, or alternatively external to the vehicle 100-2, and accessible via a wireless interface. ln the database 350, different geographical positions are stored associated with a respec- tive road slope values, which may be extracted by using a geographical position and a di- rection as input values.

The topography of the upcoming road section 220-2 is important when determining the velocity profile for the vehicles 100-1, 100-2, 100-3 in the platoon 110. For example, when arriving at a long and steep downhill, any, some or all of the vehicles 100-1, 100-2, 100-3 may like to modify a mode or state of the vehicle 100-1, 100-2, 100-3, such as e.g. velocity and/ or the charge level of the battery etc., in order to upload the battery when rolling down the hill.

The vehicles 100-1, 100-2, 100-3 in the platoon 110 may communicate with each other over a wireless interface. Thus the first vehicle 100-1 may comprise a first transceiver 360- 1 and the second vehicle 100-2 a second transceiver 360-2.

The wireless communication may be e.g. a Vehicle-to-Vehicle (V2V) signal, or any other wireless signal based on, or at least inspired by wireless communication technology such as Wi-Fi, Wireless Local Area Network (WLAN), Ultra Mobile Broadband (UMB), Bluetooth (BT), the communication protocol IEEE 802.11p, Wireless Access in Vehicular Environ- ments (WAVE) or infrared transmission to name but a few possible examples of wireless communications.

Figure 3B also illustrates an example of an alternative embodiment of the second vehicle 100-2 in the platoon 110, previously discussed in conjunction with the presentation of Fig- ure 3A. ln this embodiment, the control unit 310 is situated outside the own vehicle 100-2, and also outside the platoon 110.

The communication between the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be made via the previously discussed wireless interface. 14 10 15 20 25 30 35 538 767 The vehicle 100-2 in the illustrated embodiments comprises a calculating unit 380, config- ured for e.g. computing a candidate velocity profile for vehicles 100-1, 100-2, 100-3 in the platoon 110 to keep at the upcoming road section 220-2 and/ or evaluating a received can- didate velocity profile, based on how preferable it would be for the own vehicle 100-2 in order to reduce a weighted sum of energy consumption and travel time of said vehicle 100- 2.

Figure 4 illustrates an example of a method 400 according to an embodiment. The flow chart in Figure 4 shows the method 400 for determining a velocity profile for each vehicle 100-1, 100-2, 100-3 in a platoon 110, comprising a grouped set of vehicles 100-1, 100-2, 100-3, for use at an upcoming road section 220-2 situated ahead of the platoon 110 in the driving direction 105.

The driving direction 105 of the vehicle 100 may be determined based on the location of the destination of the journey, or by extrapolating the driving direction based on previously determined geographical positions and possibly knowledge of the road direction, e.g. from stored map data.

The vehicles 100-1, 100-2, 100-3 may be any arbitrary kind of means for conveyance, such as a truck, a bus or a car. The number of vehicles 100-1, 100-2, 100-3 in the platoon 110 may be any number exceeding one, such as e.g. 2, 3, °<>. A typical number may be e.g. 5- 20 vehicles in a non-limiting examples.

The vehicles 100-1, 100-2, 100-3 may communicate with other vehicles 100-1, 100-2, 100- 3 in the platoon 110, and possibly also with other vehicles or entities, via wireless commu- nication signalling, based on e.g. Vehicle-to-Vehicle (V2V) communication or any other wireless communication technology such as Wi-Fi, Wireless Local Area Network (WLAN), Ultra Mobile Broadband (UMB), Bluetooth (BT), or infrared transmission to name but a few possible examples of wireless communications.

The vehicles 100-1, 100-2, 100-3 are driving in the platoon 110 with a distance t1, t2 be- tween each vehicle 100-1, 100-2, 100-3 in the platoon 110. The distance t1, t2 may be the same between all vehicles 100-1, 100-2, 100-3 in some embodiments. Alternatively, differ- ent vehicles 100-1, 100-2, 100-3 may keep a different distance t1, t2 to the vehicle 100-1, 100-2, 100-3 in front. The distance t1, t2 may also vary within an interval in some embodi- ments. The distance t1, t2 may be measured in time, then often referred to as a time gap, e.g. of 0.1 second, 1 second etc. the distance t1, t2 may alternatively be measured in 15 10 15 20 25 30 35 538 767 length distance, e.g. some centimetres, some decimetres, some meters, some tenths of meters, etc. ln some embodiments, the distances t1, t2 between the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be extended when an altitude difference between the highest and lowest point of the upcoming road section 220-2 exceeds a threshold value. Thus the platoon 110 according to those embodiments may be dissolved in hilly terrain. ln some embodiments, the distances t1, t2 may be variable based on the road slope of the upcoming road section 220-2 by increasing the distances t1, t2 when the road slope is negative, indicating downhill, or increasing the variable time gap t1, t2 when the road slope is positive, indicating uphill, in some alternative embodiments.

The velocity profiles may comprise one distinct velocity profile for each vehicle 100-1, 100- 2, 100-3 in the platoon 110 in some embodiments. However in some embodiments, the velocity profiles may comprise one velocity profile for the whole platoon 110 to share, or at least for some vehicles 100-1, 100-2, 100-3 in the platoon 110 to share. ln order to correctly be able to determine the velocity profiles, the method 400 may com- prise a number of steps 401-407. However, some of these steps 401-407 may be per- formed solely in some alternative embodiments, like e.g. step 401 or step 407. Further, the described steps 401-407 may be performed in a somewhat different chronological order than the numbering suggests. The method 400 may comprise the subsequent steps: Step 401 which may be performed only in some embodiments, comprises distributing geo- graphical information defining the upcoming road section 220-2.

The upcoming road section 220-2 may be predefined in some embodiments. ln other em- bodiments, one of the vehicles 100-1, 100-2, 100-3 in the platoon 110 may determine and define the upcoming road section 220-2.

The topography i.e. road slope of the upcoming road section 220-2 may be stored in a da- tabase 350 associated with geographical positions at the upcoming road section 220-2.

Step 402 comprises obtaining at least two candidate velocity profiles for the platoon 110 to keep at the upcoming road section 220-2 from at least two of the vehicles 100-1, 100-2, 100-3 in the platoon 110. 16 10 15 20 25 30 35 538 767 ln some embodiments, each vehicle 100-1, 100-2, 100-3 in the platoon 110 may be ena- bled to suggest at least one candidate velocity profile for the platoon 110 to keep during the upcoming road section 220-2.

There may however be vehicles 100-1, 100-2, 100-3 in the platoon 110 that do not prepare and send any candidate velocity profile.

Step 403 comprises distributing the obtained 402 candidate velocity profiles to the at least two vehicles 100-1, 100-2, 100-3 in the platoon 110. ln some embodiments, each candidate velocity profile may be distributed to all vehicles 100-1, 100-2, 100-3 in the platoon 110, for evaluation.

There may however in some embodiments be vehicles 100-1, 100-2, 100-3 in the platoon 110 that do not receive any candidate velocity profile, e.g. in case they do not desire to participate in the computations, or lack appropriate equipment for doing so.

Step 404 comprises evaluating each distributed 403 candidate velocity profile at the at least two vehicles 100-1, 100-2, 100-3, based on how preferable the respective candidate velocity profile would be for the own vehicle 100-1, 100-2, 100-3 in order to minimise, or at least reduce a weighted sum of energy consumption and travel time of said vehicle 100-1, 100-2, 100-3 with regard to topography of the upcoming road section 220-2.

Minimising, or at least reducing the weighted sum of energy consumption and travel time may comprise improve efficiency in energy conversion of the engine from fuel to mechani- cal work or (in a hybrid or electrical system) conversion from electrical to mechanical ener- gy in some embodiments.

To evaluate the candidate velocity profile with the smallest weighted sum of energy con- sumption and travel time may be e.g. the lowest possible energy consumption while pass- ing the upcoming road section 220-2 within a velocity interval, such as e.g. between 70-80 km/h (in a non-limiting example). Typically the lowest velocity in the velocity interval may be kept while driving uphill and the highest velocity in the velocity interval in the downhill. ln some embodiments, a minimum velocity may be predetermined which is has to be kept by all vehicles 100-1, 100-2, 100-3 in the platoon 110 may be determined. Also, corre- 17 10 15 20 25 30 35 538 767 spondingly, a maximum velocity may be predetermined (by legal reasons), such as e.g. 80 km/h, 90 km/h etc.

The evaluation may be based on the topography or road inclination of the upcoming road section 220-2. The road inclination will typically vary with the geographical position when driving through the upcoming road section 220-2, e.g. when driving in a hilly region. The road inclination of the upcoming road section 220-2 may be extracted from the database 350, which may be situated on board the vehicle 100-1, 100-2, 100-3, or in a database 350 external to the vehicle 100-1, 100-2, 100-3, accessible via the previously discussed wire- less interface.

The different road inclination at different geographical positions may influence different vehicles 100-1, 100-2, 100-3 in the platoon 110 differently, e.g. depending on different weight, weight/ power ratio and other parameters that may be different and unique to each vehicle 100-1, 100-2, 100-3 in the platoon 110.

The weight/ power ratio, or power loading, is a calculation commonly applied to vehicles in general, to enable the comparison of one vehicle's performance to another. lt is used as a measurement of performance of a vehicle as a whole, with the weight (or mass) of the ve- hicle divided by the engine's power output, to give a metric that is independent of the vehi- cle's size.

The weight/ power ratio of the vehicle 100-1, 100-2, 100-3 may be measured by a weight sensor on the vehicle 100-1, 100-2, 100-3, or estimated based on the load in some embod- iments, and a stored power value.

However, the road inclination may also influence the vehicles 100-1, 100-2, 100-3 based on modes or states of the vehicle 100-1, 100-2, 100-3, gear ratios in the gearbox of the vehicle 100-1, 100-2, 100-3, minimum and maximum speed of the vehicle 100-1, 100-2, 100-3, speed-dependent losses, cooling/ heating requirements, maximum torque curve, information concerning the relation between torque, engine speed and energy consump- tion, gear-shift timing, gear shift time, charging level of batteries, pressure level of pneu- matic reservoir, exhaust after treatment system temperature, emissions and similar infor- mation relevant for vehicle performance on the upcoming road section 220-2, which may be different for different vehicles 100-1, 100-2, 100-3 in the platoon 110. 18 10 15 20 25 30 35 538 767 Step 405 comprises compiling the made evaluations 404 of each distributed 403 candidate velocity profile, made by the at least two vehicles 100-1, 100-2, 100-3.

The step of compiling the made evaluations 404 may be made by a central node 100-1, 100-2, 100-3, 310 in some embodiments, such as e.g. one of the vehicles 100-1, 100-2, 100-3 in the platoon 110, such as e.g. the first vehicle 100-1 in the platoon 110.

The step of compiling the made evaluations 404 may alternatively be made by each vehicle 100-1, 100-2, 100-3 in the platoon 110, based on a shared selection algorithm, known by each vehicle 100-1, 100-2, 100-3 in the platoon 110. In some embodiments, when the ve- hicles 100-1, 100-2, 100-3 in the platoon 110 has provided a grade or similar estimation of the respective distributed 403 candidate velocity profiles, the candidate velocity profile re- ceiving the highest grade in average by the vehicles 100-1, 100-2, 100-3 in the platoon 110 may be selected.

Step 406 comprises determining the velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, to be used when driving at the upcoming road section 220-2, based on the compiled 405 evaluations 404 of the distributed 403 candidate velocity profiles.

The candidate velocity profiles that result in that a minimum distance t1, t2 between any vehicles 100-1, 100-2, 100-3 in the platoon 110 cannot be kept may be disregarded from the determined velocity profiles. The minimum distance t1, t2 may be set for security rea- sons in order to avoid a collision and may be pre-set to e.g. some centimetres, some deci- metres etc.

The determined velocity profiles may in some embodiments be based on the candidate velocity profile having received the highest evaluation 404 by any other vehicle 100-1, 100- 2, 100-3 in the platoon 110.

The determined velocity profiles may be based on a weighted interpolation made between the evaluated 404 candidate velocity profiles. Thus a combination may be made, compro- mising between the candidate velocity profiles with highest evaluations.

The step of determining the velocity profiles may be made by a central node 100-1, 100-2, 100-3, 310. The central node 100-1, 100-2, 100-3, 310 may be a vehicle 100-1, 100-2, 100-3 in the platoon 110 in some embodiments, e.g. the first vehicle 100-1. However, the 19 10 15 20 25 30 35 538 767 central node 100-1, 100-2, 100-3, 310 may in other embodiments be situated out of the platoon 110, and may comprise a separate entity such as a server.

The step of determining the velocity profiles may in some embodiments be made by each vehicle 100-1, 100-2, 100-3 in the platoon 110, based on a shared selection algorithm, known by each vehicle 100-1, 100-2, 100-3 in the platoon 110. The shared selection algo- rithm may be pre agreed upon, or distributed e.g. when the platoon 110 is formed or upon departure.

According to some embodiments, any vehicle 100-1, 100-2, 100-3 in the platoon 110 may be enabled to discard any candidate velocity profile from the velocity profiles to be deter- mined to be used by the platoon 110, when said vehicle 100-1, 100-2, 100-3 is not able to follow the candidate velocity profile, due to capacity constraints, velocity constraints etc.

Step 407 which may be performed only in some embodiments, comprises instructing each vehicle 100-1, 100-2, 100-3 comprised in the platoon 110 to start using a velocity profile in the determined 406 velocity profiles upon arrival at the upcoming road section 220-2.

Thus the vehicles 100-1, 100-2, 100-3 in the platoon 110 start using the determined veloci- ty profiles simultaneously when arriving at the upcoming road section 220-2, e.g. when the first vehicle 100-1 of the platoon 110 arrives, or when any vehicle 100-1, 100-2, 100-3 in the platoon 110 arrives at the upcoming road section 220-2.

Figure 5 illustrates an embodiment of a system 500 in a vehicle platoon 110. The system 500 comprises a control unit 310, in a vehicle 100-1, 100-2, 100-3 in the platoon 110. The control unit 310 may perform at least some of the previously described steps 401-407 ac- cording to the method 400 described above and illustrated in Figure 4 for determining a velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, comprising a grouped set of vehicles 100-1, 100-2, 100-3, for use at a upcoming road section 220-2 sit- uated ahead of the platoon 110 in the driving direction 105.

The control unit 310 is further configured for obtaining at least two candidate velocity pro- files for the platoon 110 to keep at the upcoming road section 220-2 from at least two of the vehicles 100-1, 100-2, 100-3 in the platoon 110. Further, the control unit 310 is configured for distributing the obtained candidate velocity profiles to the at least two vehicles 100-1, 100-2, 100-3 grouped in the platoon 110. Also, the control unit 310 is additionally config- ured for evaluating each distributed candidate velocity profile at the at least two vehicles 20 10 15 20 25 30 35 538 767 100-1, 100-2, 100-3, based on how preferable the respective candidate velocity profile would be for the own vehicle 100-1, 100-2, 100-3 in order to reduce a weighted sum of energy consumption and travel time of said vehicle 100-1, 100-2, 100-3 with regard to the topology of the upcoming road section 220-2. Furthermore, the control unit 310 is config- ured for compiling the made evaluations of each distributed candidate velocity profile, made by the at least two vehicles 100-1, 100-2, 100-3. The control unit 310 is also config- ured for determining the velocity profiles to be used by the platoon 110 when driving on the upcoming road section 220-2, based on the compiled evaluation of the distributed candi- date velocity profiles.

The control unit 310 may further, in some embodiments be configured for instructing each vehicle 100-1, 100-2, 100-3 comprised in the platoon 110 to start using a velocity profile in the determined velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110 upon arrival at the upcoming road section 220-2.

Also, in some embodiments, the control unit 310 may be further configured for disregarding any candidate velocity profiles that result in that a minimum distance t1, t2 between any vehicles 100-1, 100-2, 100-3 in the platoon 110 cannot be kept, from the determined ve- locity profiles.

The control unit 310 may in some embodiments be additionally configured for determining the velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, based on the candidate velocity profile having received the highest evaluation.

Further, the control unit 310 may be configured for determining the velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, based on a weighted interpolation made between the evaluated candidate velocity profiles.

Also, the control unit 310 may be configured for enabling each vehicle 100-1, 100-2, 100-3 in the platoon 110 to suggest at least one candidate velocity profile for the platoon 110 to keep during the upcoming road section 220-2.

Furthermore, the control unit 310 may also be configured for distributing each candidate velocity profile to all vehicles 100-1, 100-2, 100-3 in the platoon 110, for evaluation.

The control unit 310 may furthermore be comprised in a central node 100-1, 100-2, 100-3, 310, wherein the made evaluations may be compiled and the velocity profiles may be de- 21 10 15 20 25 30 35 538 767 termined. The central node 100-1, 100-2, 100-3, 310 may be one of the vehicles 100-1, 100-2, 100-3 in the platoon 110, such as e.g. the first vehicle 100-1 in the platoon 110, or alternatively be external to the platoon 1 10.

Alternatively, the control unit 310 may furthermore be comprised in vehicles 100-1, 100-2, 100-3 of the platoon 110, configured for compiling the made evaluations and for determin- ing the velocity profiles are made by each vehicle 100-1, 100-2, 100-3 in the platoon 110, based on a shared selection algorithm, known by each vehicle 100-1, 100-2, 100-3 in the platoon 110, in some embodiments.

Further, the control unit 310 may furthermore be comprised in vehicles 100-1, 100-2, 100-3 of the platoon 110 in some embodiments, and may be configured for enabling to discard any candidate velocity profile from the velocity profiles to be determined to be used by the platoon 110, when said vehicle 100-1, 100-2, 100-3 is not able to follow the candidate ve- locity profile.

Further, the control unit 310 may be configured for distributing geographical information defining the upcoming road section.

The control unit 310 may in some embodiments be additionally configured for extending the distances t1, t2 between the vehicles 100-1, 100-2, 100-3 in the platoon 110, when an altitude difference between the highest and lowest point of the upcoming road section 220- 2 exceeds a threshold value.

The control unit 310 may in some embodiments be additionally configured for determining one distinct velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110.

The control unit 310 may comprise a receiving circuit 510 configured for receiving wireless and/ or wired signals from e.g. a distance measuring device 320 and a positioning device 330.

The control unit 310 may also comprise a processor 520 configured for performing at least some of the calculating or computing of the control unit 310. Thus the processor 520 may be configured for determining a velocity profile for each vehicle 100-1, 100-2, 100-3 in the platoon 110, comprising a grouped set of vehicles 100-1, 100-2, 100-3, for use at an up- coming road section 220-2 situated ahead of the platoon 110 in the driving direction 105. 22 10 15 20 25 30 35 538 767 The processor 520 may thus be further configured for obtaining at least two candidate ve- locity profiles for the platoon 110 to keep at the upcoming road section 220-2 from at least two of the vehicles 100-1, 100-2, 100-3 in the platoon 110. Further, the processor 520 may be configured for distributing the obtained candidate velocity profiles to the at least two vehicles 100-1, 100-2, 100-3 grouped in the platoon 110. Also, the processor 520 may ad- ditionally be configured for evaluating each distributed candidate velocity profile at the at least two vehicles 100-1, 100-2, 100-3, based on how preferable the respective candidate velocity profile would be for the own vehicle 100-1, 100-2, 100-3 in order to reduce a weighted sum of energy consumption and travel time of said vehicle 100-1, 100-2, 100-3 with regard to the topology of the upcoming road section 220-2. Furthermore, the proces- sor 520 may be configured for compiling the made evaluations of each distributed candi- date velocity profile, made by the at least two vehicles 100-1, 100-2, 100-3. The processor 520 may also be configured for determining the velocity profile for each vehicle 100-1, 100- 2, 100-3 in the platoon 110 to be used when driving on the upcoming road section 220-2, based on the compiled evaluation of the distributed candidate velocity profiles.

Such processor 520 may comprise one or more instances of a processing circuit, i.e. a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The herein utilised expression “processor" may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones enumerated above.

Furthermore, the control unit 310 may comprise a memory 525 in some embodiments. The optional memory 525 may comprise a physical device utilised to store data or programs, i.e., sequences of instructions, on a temporary or permanent basis. According to some em- bodiments, the memory 525 may comprise integrated circuits comprising silicon-based transistors. The memory 525 may comprise e.g. a memory card, a flash memory, a USB memory, a hard disc, or another similar volatile or non-volatile storage unit for storing data such as e.g. ROIVI (Read-Only Memory), PROM (Programmable Read-Only l\/lemory), EPROIVI (Erasable PROlVl), EEPROM (Electrically Erasable PROIVI), etc. in different em- bodiments.

Further, the control unit 500 may comprise a signal transmitter 530. The signal transmitter 530 may be configured for transmitting a control signal over a wired or wireless interface to a wireless transmitter 360 which in turn may signal or broadcast wireless signals to other vehicles 100-1, 100-2, 100-3 of the platoon 110. 23 10 15 20 25 30 35 538 767 The previously described steps 401-407 to be performed in the control unit 310 may be implemented through the one or more processors 520 within the control unit 310, together with computer program product for performing at least some of the functions of the steps 401-407. Thus a computer program product, comprising instructions for performing the steps 401-407 in the control unit 310 may perform the method 400 comprising at least some of the steps 401 -407 for determining a velocity profile for vehicles 100-1, 100-2, 100- 3 in a platoon 110, comprising a grouped set of vehicles 100-1, 100-2, 100-3, for use at an upcoming road section 220-2 situated ahead of the platoon 110 in the driving direction 105, when the computer program is loaded into the one or more processors 520 of the control unit 310.

The computer program product mentioned above may be provided for instance in the form of a data carrier carrying computer program code for performing at least some of the step 401-407 according to some embodiments when being loaded into the one or more proces- sors 520 of the control unit 310. The data carrier may be, e.g., a hard disk, a CD ROIVI disc, a memory stick, an optical storage device, a magnetic storage device or any other appro- priate medium such as a disk or tape that may hold machine readable data in a non- transitory manner. The computer program product may furthermore be provided as com- puter program code on a server and downloaded to the control unit 310 remotely, e.g., over an Internet or an intranet connection.

Further, some embodiments may comprise a vehicle 100-1, 100-2, 100-3 comprising a control unit 310 as described above.

The terminology used in the description of the embodiments as illustrated in the accompa- nying drawings is not intended to be limiting of the described method 400; the control unit 310; the system 500, the computer program or the vehicle 100. Various changes, substitu- tions or alterations may be made, without departing from invention embodiments as de- fined by the appended claims.

As used herein, the term "and/ or" comprises any and all combinations of one or more of the associated listed items. The term "or" as used herein, is to be interpreted as a mathe- matical OR, i.e., as an inclusive disjunction; not as a mathematical exclusive OR (XOR), unless expressly stated othen/vise. ln addition, the singular forms "a", "an" and "the" are to be interpreted as “at least one", thus also possibly comprising a plurality of entities of the same kind, unless expressly stated otherwise. lt will be further understood that the terms 24 538 767 "includes", "comprises", "including" or "comprising", specifies the presence of stated feat- ures, actions, integers, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, actions, integers, steps, operations, elements, components, or groups thereof. A single unit such as e.g. a processor may fulfil 5 the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. A computer program may be stored/ distrib- uted on a suitable medium, such as an optical storage medium or a solid-state medium supplied together with or as part of other hardware, but may also be distributed in other 10 forms such as via Internet or other Wired or wireless communication system. 25

Claims

10 15 20 25 30 35 538 767 PATENT CLAIMS

1. A method (400) for determining a velocity profile for each vehicle (100-1, 100-2, 100-3) comprised in a platoon (110) of grouped vehicles (100-1, 100-2, 100-3), for use in an upcoming road section (220-2), situated ahead of the platoon (110) in the driving direc- tion (105), wherein the method (400) comprises: obtaining (402) at least two candidate velocity profiles for the platoon (110) to use at the upcoming road section (220-2) from at least two of the vehicles (100-1, 100-2, 100-3) in the platoon (110); distributing (403) the obtained (402) candidate velocity profiles to the at least two vehicles (100-1, 100-2, 100-3) in the platoon (110); evaluating (404) each distributed (403) candidate velocity profile at the at least two vehicles (100-1, 100-2, 100-3), based on how preferable the respective candidate velocity profile would be for the own vehicle (100-1, 100-2, 100-3) in order to reduce a weighted sum of energy consumption and travel time of said vehicle (100-1, 100-2, 100-3) with re- gard to topology of the upcoming road section (220-2); compiling (405) the made evaluations (404) of each distributed (403) candidate velocity profile, made by the at least two vehicles (100-1, 100-2, 100-3); and determining (406) the velocity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110), to be used when driving at the upcoming road section (220-2), based on the compiled (405) evaluations (404) of the distributed (403) candidate velocity profiles.

2. The method (400) according to claim 1, further comprising: instructing (407) each vehicle (100-1, 100-2, 100-3) in the platoon (110) to start using the determined (406) velocity profile upon arrival at the upcoming road section (220- 2).

3. The method (400) according to any of claim 1 or claim 2, wherein candidate veloc- ity profiles that result in that a minimum distance (t1, t2) between any vehicles (100-1, 100- 2, 100-3) in the platoon (110) cannot be kept is disregarded from the determined (406) ve- locity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110).

4. The method (400) according to any of claims 1-3, wherein the determined (406) velocity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110) is based on the candidate velocity profile having received the highest evaluation (404). 26 10 15 20 25 30 35 538 767

5. The method (400) according to any of claims 1-3, wherein the determined (406) velocity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110) is based on a weighted interpolation made between the evaluated (404) candidate velocity profiles.

6. The method (400) according to any of claims 1-5, wherein each vehicle (100-1, 100-2, 100-3) in the platoon (110) is enabled to suggest at least one candidate velocity profile for the platoon (110) to keep during the upcoming road section (220-2).

7. The method (400) according to any of claims 1-6, wherein each candidate velocity profile is distributed (403) to all vehicles (100-1, 100-2, 100-3) in the platoon (110), for evaluation (404).

8. The method (400) according to any of claims 1-7, wherein the steps of compiling (405) the made evaluations (404); and determining (406) the velocity profile for each vehi- cle (100-1, 100-2, 100-3) are made by a central node (100-1, 100-2, 100-3, 310).

9. The method (400) according to any of claims 1-7, wherein the steps of compiling (405) the made evaluations (404); and determining (406) the velocity profile for each vehi- cle (100-1, 100-2, 100-3) are made by each vehicle (100-1, 100-2, 100-3) in the platoon (110), based on a shared selection algorithm, known by said vehicles (100-1, 100-2, 100- 3).

10. 100-2, 100-3) in the platoon (110) is enabled to discard any candidate velocity profile to be determined (406), when said vehicle (100-1, 100-2, 100-3) is not able to follow the candi- date velocity profile. The method (400) according to any of claims 1-9, wherein any vehicle (100-1,

11. (401) geographical information defining the upcoming road section (220-2). The method (400) according to any of claims 1-10, further comprising distributing

12. The method (400) according to any of claims 1-11, further comprising extending the distances (t1, t2) between the vehicles (100-1, 100-2, 100-3) in the platoon (110), when an altitude difference between the highest and lowest point of the upcoming road section (220-2) exceeds a threshold value. 27 10 15 20 25 30 35 538 767

13. velocity profile for each vehicle (100-1, 100-2, 100-3) comprises one distinct velocity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110). The method (400) according to any of claims 1-12, wherein the determined (406)

14. upcoming road section (220-2), the method (400) is repeated for determining a velocity The method (400) according to any of claims 1-13, wherein upon arriving at the profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110), for use in a further up- coming road section (220-3), situated ahead of the platoon (110) in the driving direction (105).

15. 2, 100-3) comprised in a platoon (110) of grouped vehicles (100-1, 100-2, 100-3), for use in A control unit (310) for determining a velocity profile for each vehicle (100-1, 100- an upcoming road section (220-2), situated ahead of the platoon (110) in the driving direc- tion (105), wherein the control unit (310) is configured for obtaining at least two candidate velocity profiles for the platoon (110) to keep at the upcoming road section (220-2) from at least two of the vehicles (100-1, 100-2, 100-3) in the platoon (110); and configured for dis- tributing the obtained candidate velocity profiles to the at least two vehicles (100-1, 100-2, 100-3) grouped in the platoon (110); and also configured for evaluating each distributed candidate velocity profile at the at least two vehicles (100-1, 100-2, 100-3), based on how preferable the respective candidate velocity profile would be for the own vehicle (100-1, 100-2, 100-3) in order to reduce a weighted sum of energy consumption and travel time of said vehicle (100-1, 100-2, 100-3) with regard to the topology of the upcoming road section (220-2); and in addition further configured for compiling the made evaluations of each dis- tributed candidate velocity profile, made by the at least two vehicles (100-1, 100-2, 100-3); and configured for determining the velocity profile for each vehicle (100-1, 100-2, 100-3) in the platoon (110), to be used when driving on the upcoming road section (220-2), based on the compiled evaluation of the distributed candidate velocity profiles.

16. cording to any of claims 1-14 when the computer program is executed in the control unit A computer program comprising program code for performing a method (400) ac- (310), according to claim 15.

17. 15. A vehicle (100-1, 100-2, 100-3) comprising a control unit (310) according to claim 28