SE1851542A1

SE1851542A1 - A method for transferring a load between two vehicles, a control device, a computer program, a computer-readable medium and a vehicle

Info

Publication number: SE1851542A1
Application number: SE1851542A
Authority: SE
Inventors: Robert Skaba
Original assignee: Scania Cv Ab
Priority date: 2018-12-11
Filing date: 2018-12-11
Publication date: 2020-06-12

Abstract

The invention relates to a method for transferring a load (30) from a first vehicle (10) to a second vehicle (20), wherein the vehicles (10; 20) each comprises a pneumatic suspension system (18; 28) and a transfer equipment (19; 29) arranged to move the load (30) in a longitudinal direction (L) of the vehicles (10; 20), the method comprises: controlling (s104), based on a determined difference between a height (H1 ) of the first end (12) of the first vehicle (10) and a height (H2) of the first end (22) of the second vehicle (20), the pneumatic suspension system (18) of the first vehicle (10) and/or the pneumatic suspension system (28) of the second vehicle (20) to adjust at least one of the heights (H1 , H2), so that the difference between the heights (H1 , H2) is within a predetermined tolerance range.(Fig. 1)

Description

A method for transferring a load between two vehicles, a control device, a computer program, a computer-readable medium and a vehicle TECHNICAL FIELD The present invention relates to a method for transferring a load from a firstvehicle to a second vehicle, a control device, a vehicle, a computer program and a computer-readable medium.

BACKGROUND There are rnany different ways ot transferring a load, such as a cargo, loetweenvehicles. One known solution is to transfer a cargo on a conveyor or rails on thetwo vehicles, whereln the cargo is rrioved in the longitudinal direction ot thevehicles. This is tyoically used when transferring a load lrorri a trailer to a truck.in this case, the truck and the trailer rnust iirst he positioned end to end and thetruck and the trailer also oontprise corresponding coupling rneans tornechanically couple the two vehicles hetore transferring the load. When thecargo is translerred lrorri the trailer to the truck, the air suspended ohassis ot thetruck vvill he lowered hy the weight ot the cargo, and the air suspended chassisot the trailer will rise. This will exert large vertical toroes on the rneohanioalcoupling hetween the truck and the trailer. The large load on the rnechanicalcoupling will lead to potential energy heing stored up in the trailer ohassis, sirnilarto a how or catapult. This rnay he very dangerous and is stresslul tor the trailerohassis, especially the lrarne and the wheel axle closest to the inechanicalcoupling. Furthermore, when the driver ot the truck hegins to drive away,potential energy in the trailer will rriake the end ot the trailer corriprising therrieohanical ooupling rrieans spring up and hit the rear end ot the truck. Thisleads to unnecessary wear and tear. When the truck has received the cargo, thetruck should he raised to a predeterrriined driver height. This takes sorne tirne and ntay he perceived hy the driver ot the truck as unnecessary waiting tirrie.

SUMMARY OF THE INVENTION Despite known solutions in the field, it would be desirable to develop a methodfor transferring a load between two vehicles, which overcomes or at leastalleviates some of the drawbacks of the prior art.

An object of the present invention is therefore to achieve a new andadvantageous method for transferring a load from a first vehicle to a secondvehicle, which increases safety and reduces the wear and tear of the vehicles.Another object of the invention is to achieve a new and advantageous controldevice, vehicle, computer program and computer-readable medium, whichincreases safety and reduces the wear and tear.

The herein mentioned objects are achieved by a method for transferring a loadfrom a first vehicle to a second vehicle, a control device, a vehicle, a computerprogram and a computer-readable medium according to the independent claims.

Hence, according to an aspect of the present invention a method, performed bya control device, for transferring a load from a first vehicle to a second vehicle isprovided. The first vehicle and the second vehicle are positioned with a first endof the first vehicle adjacent a first end of the second vehicle, wherein the vehicleseach comprises a pneumatic suspension system and a transfer equipmentarranged to move the load in the longitudinal direction of the respective vehicle.The method comprises, when transfer of the load has been initiated: controlling,based on a determined difference between a height of the first end of the firstvehicle and a height of the first end of the second vehicle, the pneumaticsuspension system of the first vehicle and/or the second vehicle, to adjust atleast one of the heights, so that the difference between the heights is within apredetermined tolerance range.

According to another aspect of the invention, a control device configured fortransferring a load from a first vehicle to a second vehicle is provided. The firstvehicle and the second vehicle being positioned with a first end of the firstvehicle adjacent a first end of the second vehicle, wherein the vehicles eachcomprises a pneumatic suspension system and a transfer equipment arrangedto move the load in a longitudinal direction of the respective vehicle, the controldevice being configured to, when transfer of the load has been initiated: control,based on a determined difference between a height of the first end of the firstvehicle and a height of the first end of the second vehicle, the pneumaticsuspension system of the first vehicle and/or the second vehicle, to adjust atleast one of the heights, so that the difference between the heights is within apredetermined tolerance range.

Pneumatic suspension systems for levelling a vehicle are known to comprise acompressor unit supplying pressurized air into pneumatic suspension meansassociated with a wheel axle. The suspension means may comprise a flexiblebellow with a piston. When the air pressure inflates the suspension means of anaxle the vehicle chassis is raised from that axle. Similarly, when the amount ofair inside the suspension means is decreased, the suspension means is deflatedand the vehicle chassis is lowered towards the axle. Thus, by controlling thepneumatic suspension system of a vehicle, the vehicle chassis can be raised orlowered and the vehicle height above the ground may thereby be controlled. Aspreviously mentioned in the background, transferring loads between vehiclesmay result in high risks caused by potential energy being stored up in the vehicledelivering the load. Also, too large vertical forces may act on the mechanicalcoupling between the vehicles in known solutions. By automatically andcontinuously determining the height above the ground for both vehicles anddetermining the difference there between, the pneumatic suspension system ofthe vehicles can be controlled to make sure that the difference in height is withina predetermined tolerance range and thus that the vehicles are in level. Thisway, less potential energy will be stored in the delivering vehicle and there willthus be less stress on the chassis of the delivering vehicle. The vertical forces acting on an eventual mechanical coupling will be smaller and the wear and tear on such mechanical coupling would be reduced.

Further objects, advantages and novel features of the present invention willbecome apparent to one skilled in the art from the following details, and also byputting the invention into practice. Whereas embodiments of the invention aredescribed below, it should be noted that it is not restricted to the specific detailsdescribed. Specialists having access to the teachings herein will recognisefurther applications, modifications and incorporations within other fields, whichare within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS For fuller understanding of the present invention and further objects andadvantages of it, the detailed description set out below should be read togetherwith the accompanying drawings, in which the same reference notations denote similar items in the various diagrams, and in which: Figure 1 schematically illustrates two vehicles according to an example; Figure 2 schematically illustrates two vehicles according to an example; Figure 3 schematically illustrates a control device according to an example, Figure 4 schematically illustrates details of two vehicles according to anexample; Figure 5 illustrates a flow chart for a method for transferring a load betweentwo vehicles according to an example; and Figure 6 schematically illustrates a control unit or computer according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS Transferring a load between vehicles may result in unnecessary wear and tearof the vehicles and risky situations may occur. To increase safety, a method andcontrol device according to the disclosure has been developed. The presentdisclosure is applicable on load transfer between two heavy vehicles.Specifically, the present disclosure may relate to load transfer between a truckand a trailer or between two trucks. lt is, however, to be understood that thepresent disclosure also is applicable on load transfer between a vehicle and a platform.

According to an aspect of the present disclosure a method, performed by acontrol device, for transferring a load from a first vehicle to a second vehicle isprovided. The first vehicle and the second vehicle are positioned with a first endof the first vehicle adjacent a first end of the second vehicle, wherein the vehicleseach comprises a pneumatic suspension system and a transfer equipmentarranged to move the load in the longitudinal direction of the respective vehicle.The method comprises, when transfer of the load has been initiated: controlling,based on a determined difference between a height of the first end of the firstvehicle and a height of the first end of the second vehicle, the pneumaticsuspension system of the first vehicle and/or the second vehicle, to adjust atleast one of the heights, so that the difference between the heights is within a predetermined tolerance range.

The predetermined tolerance range may be stored in the control device. Thepredetermined tolerance range may be selected to only allow a difference inheight, which would reduce/minimize the stress in the first vehicle. Thepredetermined tolerance may be +/- 20 millimetres. The predeterminedtolerance range may depend on the design of the transfer equipment of the firstvehicle and the second vehicle. The predetermined tolerance range may further depend on the design/configuration of the first vehicle and the second vehicle.

The method may optionally comprise determining a height above the ground ofthe first end of the first vehicle, determining a height above the ground of thefirst end of the second vehicle, and determining a difference between the heightof the first end of the first vehicle and the height of the first end of the secondvehicle.

The first vehicle may be referred to as a delivering vehicle and the secondvehicle may be referred to as a receiving vehicle. The first vehicle may be a truckor a trailer. The second vehicle may be a truck or a trailer. Thus, the methodmay be a method for transferring a load from a trailer to a truck, from a truck toa truck, or from a truck to a trailer. The load may be a cargo, a cassette, a container or similar.

The pneumatic suspension system of each vehicle may comprise a compressorand pneumatic suspension means associated with at least one wheel axle. Thecompressor is configured for supplying pressurized air into the pneumaticsuspension means. The suspension means suitably comprises a flexible bellowwith a piston, such as for example a folding sleeve bellow. The suspensionmeans suitably comprises a rubber bellow. The suspension means is suitablyconnected to a wheel axle at one end and to the chassis at the other end. Thesuspension means may be connected to the wheel axle via a link arm. Whenthe air pressure inflates the suspension means of a wheel axle the vehiclechassis is raised from that wheel axle. Similarly, when the amount of air insidethe suspension means is decreased, the suspension means is deflated and thevehicle chassis is lowered towards the wheel axle. lt is commonly known that a certain pressure in the suspension meanscorresponds to a certain load on the suspension means. This relationship istypically stored as a pressure-to-load equation and is often used to determinethe load on the suspension means. This relationship typically depends on theeffective area of the suspension means. The load on the suspension means ofa wheel axle may be referred to as the sprung weight of the vehicle. The sprung weight is thus the mass supported by the suspension means and typicallyincludes the mass of everything above the suspension means, such as thechassis, passengers, cargo etc. The sprung weight may also include part of themass of the pneumatic suspension system itself. Thus, based on the pressurein the suspension means, the sprung weight of the vehicle can be determined. lt is to be understood that the control device performing the disclosed methodmay be implemented as a separate entity or distributed in two or more physicalentities. The control device may comprise one or more control units and/orcomputers. The control device may thus be implemented or realised by thecontrol device comprising a processor and a memory, the memory comprisinginstructions, which when executed by the processor causes the control deviceto perform the herein disclosed method steps.

According to one example, the first vehicle comprises a first control unit and thesecond vehicle comprises a second control unit. The first control unit may bearranged in communication with the pneumatic suspension system and thetransfer equipment of the first vehicle. The second control unit may be arrangedin communication with the pneumatic suspension system and the transferequipment of the second vehicle. The first control unit and the second controlunit may be configured to communicate with each other. The first control unitand the second control unit may be configured to communicate with each otherwirelessly and/or via a physical electronic connection. The control device maythus comprise the first control unit and the second control unit. Alternatively, thecontrol device is comprised in the any one of the first and the second vehicleand thus comprises either the first control unit or the second control unit.

The first end of the first vehicle may be referred to as the rear end of the firstvehicle or as the front end of the first vehicle. The first end of the second vehicle may be referred to as the rear end of the second vehicle.

According to an example, the first vehicle and the second vehicle are notmechanically connected during the method. Thus, mechanical coupling meansare not required when transferring the load between the vehicles according tothe disclosed method. Since the control units of the vehicles communicate witheach other and continuously coordinates the vehicle heights and the loadtransfer, the mechanical connection is no longer necessary to keep the vehicleat the same height. Without the strong and stiff mechanical coupling, thevehicles will be less bulky and have a reduced weight. The control units of thevehicles may communicate when the vehicles are positioned adjacent eachother and the mechanical connection is thus not required to ensure that thevehicles are arranged adjacent each other. ln one example, the methodcomprises controlling the first vehicle and the second vehicle so that they arealigned. The second vehicle may autonomously align itself with the first vehicleor vice versa. The first vehicle and/or the second vehicle may thus beautonomously operated to a suitable distance from the other vehicle and/or beautonomously steered to be laterally aligned with the other vehicle. The methodmay comprise controlling the first vehicle and/or the second vehicle to a positionwhere a first end of the first vehicle is adjacent a first end of the second vehicle.The method may comprise controlling the second vehicle to a position where afirst end of the first vehicle is adjacent a first end of the second vehicle. Thecontrol device may determine when the first vehicle and the second vehicle arein a correct position in relation to each other. The control device may determinethat the first vehicle and the second vehicle are in a correct position in relationto each other based on signals from at least one proximity sensor arranged onthe second vehicle and/or the first vehicle. The at least one proximity sensor may be arranged in communication with the control device.

Determining the height above the ground of the first end of the first vehicle maybe performed by means of a height sensor device arranged on the first vehicle.Such sensor devices may comprise a potentiometer, laser sensor, ultra soundsensor, a radar, a Lidar or the like. The height sensor device is arranged oncommunication with the first control unit. ln the event that the control device comprises only the second control unit of the second vehicle, the control devicemay determine the height of the first vehicle by receiving information regardingthe height from the first control unit of the first vehicle. Suitably, determining theheight above the ground of the first end of the first vehicle may comprisedetermining the height above the ground of a floor surface at the first end of thefirst vehicle. The floor surface of the first vehicle is the floor surface on which the load is positioned and moved.

Determining the height above the ground of the first end of the second vehiclemay be performed by means of a height sensor device arranged on the secondvehicle. Such sensor devices may comprise a potentiometer, laser sensor, ultrasound sensor, a radar, a Lidar or the like. The height sensor device is arrangedin communication with the second control unit. ln the event that the controldevice comprises only the first control unit of the second vehicle, the controldevice may determine the height of the second vehicle by receiving informationregarding the height from the second control unit of the second vehicle. Suitably,determining the height above the ground of the first end of the second vehiclemay comprise determining the height above the ground of a floor surface at thefirst end of the second vehicle. The floor surface of the second vehicle is thefloor surface on which the load will be positioned and moved.

Determining a difference between the height of the first end of the first vehicleand the height of the first end of the second vehicle may be performed by thesecond control unit in the second vehicle and/or the first control unit in the firstvehicle.

According to an example, the method further comprises controlling therespective transfer equipment based on the determined difference in height. Thetransfer equipment of the first vehicle and the transfer equipment of the secondvehicle may comprise a conveyor, belt, rail or similar. The transfer equipment ofthe first vehicle may be configured to move the load linearly along a floor surfaceof the first vehicle. The transfer equipment of the second vehicle may be configured to move the load linearly along a floor surface of the second vehicle.Thus, when the first vehicle and the second vehicle are positioned end to end,the load can be transferred from the first vehicle to the second vehicle in thelongitudinal direction of the vehicles. By means of such transfer equipment, theload will gradually be transferred from the first vehicle to the second vehicle.This means that the weight of the load gradually will be transferred from the firstvehicle to the second vehicle. Thus, as the load is moved over to the secondvehicle the load/weight on the air suspension means of the first vehicle willdecrease, and the load/weight on the air suspension means of the secondvehicle will increase. When the load/weight on the air suspension means of thefirst vehicle decreases, the air suspension means will decompress. Similarly,when the load/weight on the air suspension means of the second vehicleincreases, the air suspension means will be compressed. By controlling thetransfer equipment, the movement of the load can be coordinated with thecontrol of the pneumatic suspension systems to make sure that the differencein height is maintained within the predetermined tolerance range. ln the event that the control device is comprised in the second vehicle and thuscomprises the second control unit, controlling the pneumatic suspension systemof the first vehicle based on the determined difference in height may comprisetransmitting instructions to the first control unit of the first vehicle. Also, in theevent that the control device is comprised in the second vehicle and thuscomprises the second control unit, controlling the transfer equipment of the firstvehicle based on the determined difference in height may comprise transmittinginstructions or control signals to the first control unit of the first vehicle. Similarly,in the event that the control device is comprised in the first vehicle and thuscomprises the first control unit, controlling the pneumatic suspension system ofthe second vehicle based on the determined difference in height may comprisetransmitting instructions to the second control unit of the second vehicle andcontrolling the transfer equipment of the second vehicle based on thedetermined difference in height may comprise transmitting instructions or controlsignals to the second control unit of the second vehicle. 11 According to an example, controlling the respective transfer equipmentcomprises deactivating the transfer equipment of each vehicle when thedifference in height is outside the predetermined tolerance range. Alternatively,controlling the respective transfer equipment comprises controlling the transferequipment of each vehicle to reduce the moving speed of the load when thedifference in height is outside the predetermined tolerance range. By stoppingthe transfer of the load or reducing the transfer pace (moving speed) when thedifference in height is outside a predetermined tolerance range, the control ofthe height of the vehicles and the weight of the load acting on each vehicle canbe coordinated in a better way. Thus, by stopping the transfer of the load orreducing the transfer pace, it is avoided that the height difference increasesfurther outside the predetermined tolerance range. Controlling the respectivetransfer equipment may comprise continually adjusting the moving speed of theload to match the rate of change of the difference in heights during the transferof the load. The moving speed may be adjusted at the beginning from judgingthe loads on the vehicles at the start and may apply a self-learning algorithm.

According to an example, the method further comprises determining theinclination of the first vehicle and the inclination of the second vehicle; andcontrolling the pneumatic suspension system of the first vehicle and/or thesecond vehicle based on a difference in inclination, so that the difference ininclination is within a predetermined tolerance range. Suitably, the methodcomprising determining the inclination of the first end of the first vehicle, and theinclination of the first end of the second vehicle. When the two vehicles havesimilar inclinations, transfer of the load will be facilitated. Determining theinclination of the first vehicle may be based on inclination information from aninclination sensor device arranged on the first vehicle. Determining theinclination of the second vehicle may be based on inclination information froman inclination sensor device arranged on the second vehicle. Such inclination sensor devices may comprise a potentiometer, laser sensor, ultra sound sensor, 12 a radar, a Lidar, chassis height sensors at front and rear of each vehicle, or thelike.

According to an example, the first vehicle and the second vehicle are connectedby a mechanical coupling, wherein the method further comprises: determining avertical loading on the mechanical coupling, wherein the step of controlling thepneumatic suspension system of the first vehicle and/or the second vehicle isfurther based on the determined vertical loading. The first vehicle and thesecond vehicle may comprise corresponding mechanical coupling means. As anexample, the first vehicle may comprise protrusions configured to be inserted incorresponding recesses of the second vehicle. Alternatively, the second vehiclecomprises protrusions configured to be inserted into corresponding recesses ofthe first vehicle. To avoid excessive vertical loading on the mechanical coupling,the vertical loading on the mechanical coupling is continuously determined andthe pneumatic suspension systems are controlled by taking the vertical loadinginto consideration. The vertical loading may be determined based on the weightof the first vehicle and the weight of the second vehicle. Suitably, the verticalloading may be determined based on the sprung weight of the first vehicle andthe sprung weight of the second vehicle. The vertical loading may thus becalculated based on pressure signals from the air suspension means. Bydetermining the weight of each vehicle, it can be determined to what extent theload has been transferred.

The method may further comprise controlling the pneumatic suspension systemof the first vehicle and/or the second vehicle to allow air to flow from thepneumatic suspension system of the first vehicle to the pneumatic suspensionsystem of the second vehicle. ln one example, the first vehicle and the secondvehicle comprises a pneumatic coupling connecting the pneumatic suspensionsystems of the two vehicles. By means of the pneumatic coupling, the firstvehicle and the second vehicle may share their pneumatic suspension systemsand this way assist one another. The pneumatic coupling may be integrated inthe mechanical coupling or it may be a separate coupling. The connection by 13 means of the pneumatic coupling may be performed automatically when the firstvehicle and the second vehicle are positioned adjacent each other. Thepneumatic suspension system of the second system may comprise acontrollable valve, which in the activated state allows air from the first vehicle toflow into the pneumatic suspension system of the second vehicle. Thepneumatic suspension system of the first vehicle may furthermore comprise amechanically actuated valve. The mechanically actuated valve may be actuatedby the moving load. Thus, when the load has been transferred to a certainposition the mechanically actuated valve is actuated to an open state, andthereby allowing air in the pneumatic suspension system of the first vehicle toflow through the pneumatic coupling to the second vehicle. By allowing air fromthe pneumatic suspension system of the first vehicle to flow into the pneumaticsuspension system of the second vehicle, the second vehicle will get help tocontrol the pressure in the air suspension means. The height of the secondvehicle can thereby be controlled in a faster and easier way. The pneumaticsuspension systems may be controlled to allow air from the first vehicle to flowinto the second vehicle based on the weight of the load and/or how much of theload that has been transferred to the second vehicle. lf the load is lightweight,using additional air from the first vehicle may make the levelling of the second vehicle too fast.

According to an example, the method further comprises, as the load is beingtransferred, controlling the speed of a compressor of the second vehicle toincrease the amount of air in the pneumatic suspension system of the secondvehicle. By controlling the speed of the compressor, the compressor of thepneumatic suspension system will generate more compressed air. This way, thesecond vehicle can more quickly be raised to a predetermined drive height andthe second vehicle can thereby drive off.

According to another aspect of the disclosure, a control device configured fortransferring a load from a first vehicle to a second vehicle is provided. The firstvehicle and the second vehicle being positioned with a first end of the first 14 vehicle adjacent a first end of the second vehicle, wherein the vehicles eachcomprises a pneumatic suspension system and a transfer equipment arrangedto move the load in a longitudinal direction of the respective vehicle, the controldevice being configured to, when transfer of the load has been initiated: control,based on a determined difference between a height of the first end of the firstvehicle and a height of the first end of the second vehicle, the pneumaticsuspension system of the first vehicle and/or the second vehicle, to adjust atleast one of the heights, so that the difference between the heights is within apredetermined tolerance range. lt will be appreciated that all the embodiments described for the method aspectof the disclosure are also applicable to the control device aspect of thedisclosure. That is, the control device may be configured to perform any one ofthe steps of the method according to the various examples described above.

The present disclosure will now be further illustrated with reference to the appended figures.

Figure i schernatically shows a first vehicle fi) and a second vehicle 20according to an example. The first vehicle fi) cornprlses a first end 'i2 and asecond end ia. The first vehicle to ccrnprises a prcpulsion unit l3, such as aninternal cornbustion engine or an electrical rnachine. The second vehicle 20corriprises a first end 22 and a second end 24. The second vehicle 2G comprisesa propulsion unit 23, such as an internal corntïiusrtion engine or an electricalmachine. The first vehicle ti) oornprises a olurality of vvheel axles 16, apneumatic suspension system fâ and a transfer equipment få. The secondvehicle 20 coinprises a plurality of vvheel axles 26, a pneumatic suspensionsystern 28 and a transfer equipment 29. The transfer equipment 19 of the firstvehicle 10 and the transfer equipment 29 of the second vehicle 20 may comprisea conveyor, belt, rail or similar. The first vehicle ti) is carrying a load 30. Theload 30 is about to be transferred to the second vehicle 2G hy moving it in thelongitudinal direction L of the vehicles tu, 20 by rneans of the respective transfer equipment t9, 29, Te transfer the iead 30 between the vehicies t0, 20, thevehicies t0, 20 are positioned so that the tirst end 12 ot the first vehicie t0 isadfaoent the first end 22 ef the secend vehicie 20. The height above the groundfit et the first vehieie 10, and the height above the ground H2 of the secondvehioie 20, shouid suitabiy be en the sarne fevei vvhen transferring the ioad 30.fviere specitieeffy, the height above the ground i-tt et a first ffoer surface tå atthe first end 12 ot the tirst vehieie t0 shouid he on the sarne ievei as the heightabove the ground H2 ef a fioer surface 25 at the first end 22 of the secend vehicie20.

The first vehicie t0 eoniprises a first controi unit t00 and the second vehieie 20cernprises a second centret unit 200. The first centroi unit t00 end the secendcontroi unit 200 rnay be arranged in communication vvith each other. The tirsteentrei unit t00 and/or the second centret unit 200 rnay ioe cernprised in a eentrei device 300 as disciesed in Figure 3.

Figure 2 sehentaticatfy shows a first vehieie "i0 and a second vehicfe 20according to an exerripte. The first vehiefe “i0 end the second vehicfe 20 rnay heeentigured es diseiosed in Figure t . The first vehicfe t0 eernprises a tirst end 12and e seeend end ta. The first vehieie t0 cernprises a prepuisien unit tíš, suchas an internai cornbustion engine er an efectrieai rnaohine. The second vehicie20 cornprises a first end 22 and e seeend end 24. The seeend vehieie 20contprises a propuisien unit 23,, such as an internai cornbustion engine er eneiectricat rnachine. The first vehicie t0 cernprises a piuraiity ef vvheei axies td,a pneurnatic suspension systern t8 and e transfer eouiprnent te. The secondvehieie 20 ceniprises a pturafity ef vvheei axies 26, a pneuniatic suspensionsystern 28 and a transfer equipment 29. The tirst vehicie 10 is carrying a foad30. The ioed 30 is about to be transferred te the second vehicie 20 by rneving itin the fongituciinai direction ef the vehiefes t0, 20 by rneens of the respectivetransfer eduipnfrent t0, 29. Te transfer the fead 30 between the vehieies t0, 20,the vehicies 10, 20 are pesitiened se that the first end t2 ef the first vehicte t0is adjecent the first end 22 ot the second vehiefe 20. The height above the 16 ground Ht of the first vehicte tt), and the height above the ground H2 of thesecond vehicte 2G, sheuid suitabiy be en the same tevei when transferring theieed 30. tviore seecificaiiy, the height abeve the ground Ht ef e first fieer surfacefå at the first end t? of the first vehicie ttt shoutd be en the same tevet as theheight ebeve the greund H2 of a fteer surface 25 at the first end 22 ef the secendvehicie 2G.

The first vehicte it) cerrrprises a first centret unit tGG and the second vehicie 2Gcernprises a secend centret unit 209. "the first centret unit tub and the secendcentret unit 200 may be arranged in communication with each ether. The firstcentret unit titt) and/er the secend centret unit QÜG rnay be cernprised in a centret device SGO es dtsciosed in Figure 3. in this exarnete, the first vehicte tO and the secend vehicte 20 are connected viaa mechanicat coupiing 40. The figure shews a situatien where the teact 3G hasbeen trensferred te the secend vehicte 2G. At this stage, the iead 30 arrangeden the secend vehicie 20 witi affect the eneurttatic suspension systern 28 et thesecend vehicie 2G and decrease the height aheve the greund H2 ef the secondvehicte 29. Since the vehictes tO, 2G ere cennected via the rnechenicat coupting40 a verticat ferce downwards wifi act en the first end 't2 ef the first vehicie ti)and e verticet force upwards witt act en the secend end 14 ef the tirst vehicte ti).tt is thus important that the first vehicie ti) and the second vehicie 20 are at thesarrie height befere the secend vehicte 20 drives eff and disconnects frem thefirst vehicte it).

Figure 3 schematicetiy ittustrates a centret device BGC) cenfigured ter transferringa toad frem a first vehicie te a secend vehicie according te an examete. 'thecentret device SCC) may tee esseciated with the first vehicie “iO and the secendvehicie 20 as disctesed in Figure t and Figure 2. The control device 300 may beimplemented as a separate entity or may comprise a plurality of entities, such as control units or computers, as illustrated by the dashed boxes in the figure. 17 The centret device 300 rnay cernprise the first centret unit 100 of the first vehicie10 end/er the second eentref unit 200 of the second vehicie 20.

The eentroi device 300 may be configured te determine a height abeve thegrctrnd fit ef the first end 12 ef the first vehicfe t0; determine a height ebcvethe ground H2 ef the first end 22 ef the secend vehieie 20; determine a differencebetween the height above the ground H1 ef the first end t2 ef the first vehieie10 and the height above the gretirid H2 ef the first end 22 of the secend vehieie20. The eentrei deviee 300 rney be configured te centret the pneumaticsuspension system 18 ef the first vehicie 10 and/er the pneumatic suspensionsystem 28 ef the second vehicie 20 based eri the determined difference inheight. se that the difference in height is within e predetermined teierence renge.

The control device 300 may be configured to control the respective transferequipment 19, 29 based on the determined difference in height. The controldevice 300 may also be configured to control the transfer equipment 19, 29 ofeach vehicle 10, 20 to reduce the moving speed of the load 30 when thedifference in height is outside the predetermined tolerance range. The controldevice 300 may be configured to deactivate the transfer equipment 19, 29 of thevehicles 10, 20 when the difference in height is outside the predetermined tolerance range.

The control device 300 may also be configured to determine a vertical loadingon a mechanical coupling 40 connecting the first vehicle 10 and the secondvehicle 20; and control the pneumatic suspension system 18 of the first vehicle10 and/or the pneumatic suspension system 28 of the second vehicle 20 furtherbased on the determined vertical loading. The control device 300 may beconfigured to determine the vertical loading based on the weight of the firstvehicle 10 and the weight of the second vehicle 20. The control device 300 maythus be configured to determine the weight of the first vehicle 1 and the weight of the second vehicle 20. The weight of the first vehicle 10 and the second 18 vehicle 20 may be determined based on pressure signals from air suspensionmeans 54, 74 of the respective pneumatic suspension system 18, 28.

The control device 300 may further be configured to control the pneumaticsuspension system 18 of the first vehicle 10 and/ or the pneumatic suspensionsystem 28 of the second vehicle 20 to allow air to flow from the pneumaticsuspension system 18 of the first vehicle 10 to the pneumatic suspensionsystem 28 of the second vehicle 20. The control device 300 may be configuredto control a controllable valve 76 of the pneumatic suspension system 28 of thesecond vehicle 20, to allow air from the first vehicle 10 to flow into the secondvehicle 20.

The control device 300 may also be configured to control the speed of acompressor (not shown) of the second vehicle 20 to increase the amount of airin the pneumatic suspension system 28 of the second vehicle 20. The controldevice 300 may also be configured to control the speed of a compressor (notshown) of the first vehicle 10 to increase the amount of air in the pneumaticsuspension system 18 of the first vehicle 10.

Figure 4 schematically illustrates details of two vehicles according to an example.

Figure 4 shows the pneumatic suspension system 18 of the first vehicle 10 andthe pneumatic suspension system 28 of the second vehicle 20 according to anexample. ln this example, the pneumatic suspension systems 18, 28 of the twovehicles 10, 20 are connected via a pneumatic coupling 60. The pneumaticcoupling 60 may be integrated in the mechanical coupling 40 or it may be aseparate coupling.

The pneumatic suspension system 18 of the first vehicle 10 comprises acompressor 50, an air reservoir 52 and air suspension means 54 associated withat least one wheel axle 16. The compressor 50 is configured for supplyingpressurized air to the air suspension means 54. The propulsion unit 13 of thefirst vehicle 10 may be connected to the compressor 50. Furthermore, the first 19 control unit 100 may be comprised in the pneumatic suspension system 18. Thefirst control unit 100 may be connected to the propulsion unit 13, the compressor50 and the air suspension means 54. The air suspension means 54 may befiexible rubber beiiovvs.

The pneumatic suspension system 18 of the first vehicle 10 may furthermorecomprise a mechanically actuated valve 56. The mechanically actuated valve56 may be actuated by the moving load 30. Thus, when the load 30 has beentransferred to a certain position the mechanically actuated valve 56 is actuatedto an open state, and thereby allowing air in the pneumatic suspension system18 of the first vehicle 10 to flow through the pneumatic coupling 60 to the secondvehicle 20.

The pneumatic suspension system 28 of the second vehicle 20 comprises acompressor 70, an air reservoir 72 and air suspension means 74 associated withat least one wheel axle 26. The compressor 70 is configured for supplyingpressurized air to the air suspension means 74. The propulsion unit 23 of thesecond vehicle 20 may be connected to the compressor 70. Furthermore, thesecond control unit 200 may be comprised in the pneumatic suspension system28. The second control unit 200 may be connected to the propulsion unit 23, thecompressor 70 and the air suspension means 74. The air suspension means 74may be fiexibie rubber bellovvs.

The pneumatic suspension system 28 of the second vehicle 20 may furthercomprise a controllable valve 76, which in the open state allows air from the firstvehicle 10 to flow into the pneumatic suspension system 28 of the secondvehicle 20. The controllable valve 76 may be controlled by the second controlunit 200.

Figure 5 illustrates a flow chart for a method for transferring a load from a first vehicle to a second vehicle. The method may relate to the first vehicle 1 and the second vehicle 2 as disclosed in Figure 1-4. The method is performed by acontrol device 300 as disclosed in Figure 3.

The method comprises, when transfer of the load has been initiated; contro||ings104, based on a determined difference between a height H1 of the first end 12of the first vehicle 10 and a height H2 of the first end 22 of the second vehicle20, the pneumatic suspension system 18 of the first vehicle 10 and/or thepneumatic suspension system 28 of the second vehicle 20, to adjust at least oneof the heights H1 , H2, so that the difference between the heights H1 , H2 is withina predetermined tolerance range.

The method may optionally comprise determining s101 a height above theground H1 of the first end 12 of the first vehicle 10; determining s102 a heightabove the ground H2 of the first end 22 of the second vehicle 20; anddetermining s103 a difference between the height of the first end 12 of the firstvehicle 10 and the height of the first end 22 of the second vehicle 20.

The step of determining s101 the height above the ground H1 of the first end 12of the first vehicle 10 may be performed by means of a height sensor devicearranged on the first vehicle 10. Such sensor devices may comprise apotentiometer, a laser sensor, ultra sound sensor, a radar, a Lidar or the like.

The step of determining s102 the height above the ground H2 of the first end 22of the second vehicle 20 may be performed by means of a height sensor devicearranged on the second vehicle 20. Such sensor devices may comprise apotentiometer, a laser sensor, ultra sound sensor, a radar, a Lidar or the like.

The method optionally comprises contro||ing s105 the respective transferequipment 19, 29 based on the determined difference in height. By means ofthe transfer equipment 19, 29, the load 30 will gradually be transferred from thefirst vehicle 10 to the second vehicle 20. By contro||ing s105 the transferequipment 19, 29, the movement of the load 30 can be coordinated with the 21 control of the pneumatic suspension systems 18, 28 to make sure that thedifference in height is maintained within the predetermined tolerance range.Controlling s105 the respective transfer equipment 19, 29 may comprisedeactivating the transfer equipment 19, 29 of each vehicle 10, 20 when thedifference in height is outside the predetermined tolerance range. Alternatively,contro||ing s105 the respective transfer equipment 19, 29 comprises contro||ingthe transfer equipment 19, 29 of each vehicle 10, 20 to reduce the moving speedof the load 30 when the difference in height is outside the predeterminedtolerance range. Alternatively, contro||ing s105 the respective transferequipment 19, 29 comprises adjusting the moving speed of the load 30 (transfer speed) to match the rate of change of difference in height.

The method may optionally comprise determining s106 a vertical loading on themechanical coupling 49, wherein the step of contro||ing s104 the pneumaticsuspension system 18 of the first vehicle 10 and/or the pneumatic suspensionsystem 28 of the second vehicle 20 is further based on the determined vertical loading.

The method may optionally comprise contro||ing s107 the pneumatic suspensionsystem 18 of the first vehicle 10 and/or the pneumatic suspension system 28 ofthe second vehicle 20 to allow air to flow from the pneumatic suspension system18 of the first vehicle 10 to the pneumatic suspension system 28 of the secondvehicle 20. Controlling s107 the pneumatic suspension system 18 of the firstvehicle 10 and/or the pneumatic suspension system 28 of the second vehicle 20to allow air to flow from the pneumatic suspension system 18 of the first vehicle10 to the pneumatic suspension system 28 of the second vehicle 20 maycomprise contro||ing a controllable valve 76 of the second vehicle 20. Thepneumatic suspension systems 18, 28 may be controlled s107 to allow air fromthe first vehicle 10 to flow into the second vehicle 20 based on the weight of theload 30 and/or how much of the load 30 that has been transferred to the secondvehicle 20. 22 The method may further comprise, when the load 30 has been transferred,controlling s108 the rotational speed of a propulsion unit 23 of the second vehicle20 to increase the amount of air in the pneumatic suspension system 28 of thesecond vehicle 20. lt is to be understood that the method steps of determining s101 the heightabove the ground H1 of the first vehicle 10, determining s102 the height abovethe ground H2 of the second vehicle 20, determining s103 the difference inheight and controlling s104 the pneumatic suspension systems 18, 28 based onthe determined height difference are performed repeatedly and continuouslyduring the transfer of the load 30. Also, the step of controlling the respectivetransfer equipment 19, 29 is performed repeatedly and continuously during thetransfer of the load 30.

Figure 6 is a diagram of a version of a device 500. The control device 300described with reference to Figure 1 and Figure 2 may in a version comprise thedevice 500. The device 500 comprises a non-volatile memory 520, a dataprocessing unit 510 and a read/write memory 550. The non-volatile memory 520has a first memory element 530 in which a computer programme, e.g. anoperating system, is stored for controlling the function of the device 500. Thedevice 500 further comprises a bus controller, a serial communication port, I/Omeans, an A/D converter, a time and date input and transfer unit, an eventcounter and an interruption controller (not depicted). The non-volatile memory520 has also a second memory element 540.

There is provided a computer programme P which comprises routines fortransferring a load from a first vehicle to a second vehicle. The computerprogramme P further comprises routines for determining a height above theground of the first vehicle; determining the height above the ground of thesecond vehicle; determining a difference between the height of the first and thesecond vehicle; and controlling the pneumatic suspension system of the firstand/or the second vehicle based on the determined difference in height, so that 23 the difference in height is within a predetermined tolerance range. Theprogramme P may be stored in an executable form or in a compressed form in a memory 560 and/or in a read/write memory 550.

Where the data processing unit 510 is described as performing a certain function,it means that the data processing unit 510 effects a certain part of theprogramme stored in the memory 560 or a certain part of the programme storedin the read/write memory 550.

The data processing device 510 can communicate with a data port 599 via adata bus 515. The non-volatile memory 520 is intended for communication withthe data processing unit 510 via a data bus 512. The separate memory 560 isintended to communicate with the data processing unit 510 via a data bus 511.The read/write memory 550 is adapted to communicating with the dataprocessing unit 510 via a data bus 514.

When data are received on the data port 599, they are stored temporarily in thesecond memory element 540. When input data received have been temporarilystored, the data processing unit 510 is prepared to effect code execution asdescribed above.

Parts of the methods herein described may be effected by the device 500 bymeans of the data processing unit 510, which runs the programme stored in thememory 560 or the read/write memory 550. When the device 500 runs theprogramme, methods herein described are executed.

The foregoing description of the preferred embodiments of the present inventionis provided for i||ustrative and descriptive purposes. lt is not intended to beexhaustive or to restrict the invention to the variants described. l\/lanymodifications and variations will obviously be apparent to one ski||ed in the art.The embodiments have been chosen and described in order best to explain the principles of the invention and its practical applications and hence make it 24 possible for specialists to understand the invention for various embodiments andwith the various modifications appropriate to the intended use.

Claims

1. A method, performed by a control device (300), for transferring a load (30)from a first vehicle (10) to a second vehicle (20), the first vehicle (10) and thesecond vehicle (20) being positioned with a first end (12) of the first vehicle (10)adjacent a first end (22) of the second vehicle (20), wherein the vehicles (10;20) each comprises a pneumatic suspension system (18; 28) and a transferequipment (19; 29) arranged to move the load (30) in a longitudinal direction (L)of the respective vehicle (10; 20), the method comprises, when transfer of theload (30) has been initiated: controlling (s104), based on a determined difference between aheight (H1) of the first end (12) of the first vehicle (10) and a height (H2) of thefirst end (22) of the second vehicle (20), the pneumatic suspension system(18) of the first vehicle (10) and/or the pneumatic suspension system (28) ofthe second vehicle (20) to adjust at least one of the heights (H1, H2), so thatthe difference between the heights (H1, H2) is within a predetermined tolerance range.

2. The method according to claim 1, wherein the method further comprises:controlling (s105) the respective transfer equipment (19; 29) basedon the determined difference in height.

3. The method according to claim 2, wherein controlling (s105) the respectivetransfer equipment (19; 29) comprises controlling the transfer equipment (19;29) of each vehicle (10; 20) to reduce the moving speed of the load (30) whenthe difference in height is outside the predetermined tolerance range.

4. The method according to claim 2, wherein controlling the respective transferequipment (19; 29) comprises deactivating the transfer equipment (19; 29) ofeach vehicle (10; 20) when the difference in height is outside the predetermined tolerance range. 26

5. The method according to any one of the preceding claims, wherein the firstvehicle (10) and the second vehicle (20) are connected by a mechanicalcoupling (40), wherein the method further comprises: determining (s106) a vertical loading on the mechanical coupling(40),wherein the step of controlling (s104) the pneumatic suspension system (18) ofthe first vehicle (1 0) and/or the pneumatic suspension system (28) of the secondvehicle (20) is further based on the determined vertical loading.

6. The method according to claim 5, wherein the vertical loading is determined(s106) based on the weight of the first vehicle (10) and the weight of the secondvehicle (20).

7. The method according to any one of the preceding claims, wherein themethod further comprises: controlling (s107) the pneumatic suspension system (18) of the firstvehicle (10) and/or the pneumatic suspension system (28) of the second vehicle(20) to allow air to flow from the pneumatic suspension system (18) of the first vehicle (10) to the pneumatic suspension system (28) of the second vehicle (20).

8. The method according to any one of the preceding claims, wherein themethod further comprises, as the load (30) is being transferred: controlling (s108) the speed of a compressor (70) of the secondvehicle (20) to increase the amount of air in the pneumatic suspension system(28) of the second vehicle (20).

9. A computer program (P) comprising instructions which, when the program isexecuted by a computer (300; 500), cause the computer (300; 500) to carry outthe method according to any one of the preceding claims. 27

10. A computer-readable medium comprising instructions, which when executedby a computer (300; 500), cause the computer (300; 500) to carry out the method according to any one of c|aims 1-8.

11. A control device (300) configured for transferring a load (30) from a firstvehicle (10) to a second vehicle (20), the first vehicle (1 0) and the second vehicle(20) being positioned with a first end (12) of the first vehicle (10) adjacent a firstend (22) of the second vehicle (20), wherein the vehicles (10; 20) eachcomprises a pneumatic suspension system (18; 28) and a transfer equipment(19; 29) arranged to move the load (30) in a longitudinal direction (L) of therespective vehicle (10; 20), the control device (300) being configured to, whentransfer of the load (30) has been initiated:control, based on a determined difference between a height (H1) of the first end (12) of the first vehicle (10) and a height (H2) of the first end(22) of the second vehicle (20), the pneumatic suspension system (18) of thefirst vehicle (10) and/or the pneumatic suspension system (28) of the secondvehicle (20), to adjust at least one of the heights (H1, H2), so that thedifference between the heights (H1, H2) is within a predetermined tolerance range.

12. A vehicle (10; 20) comprising a pneumatic suspension system (18; 28) anda transfer equipment (19; 29) arranged to move a load (30) in a longitudinaldirection (L) of the vehicle (10; 20), the vehicle (10; 20) further comprising acontrol device (300) according to claim 11.