SE540470C2

SE540470C2 - Method and control unit for positioning a vehicle

Info

Publication number: SE540470C2
Application number: SE1550509A
Authority: SE
Inventors: Claesson André; Sjödin Robert
Original assignee: Scania Cv Ab
Priority date: 2015-04-28
Filing date: 2015-04-28
Publication date: 2018-09-18
Also published as: SE1550509A1; DE102016004610A1

Abstract

SUMMARYMethod (400) and control unit (300) in a vehicle (100), for positioning a vehicle (100) with a roof mounted pantograph (130) laterally in relation to an energy transfer segment (120) above the vehicle (100). The method (400) comprises detecting (401) the energy transfer segment (120); defining (402) a left lateral sway limit (140) on the left side of the pantograph (130) and a right lateral sway limit (150) on the right side of the pantograph (130), in the driving direction (105) of the vehicle (100); determining (403) lateral position of the energy transfer segment (120) in relation to the defined (402) lateral sway limits (140, 150); and indicating (404) to the driver when the determined (403) lateral position of the energy transfer segment (120) is not within said lateral sway limits (140, 150).SUMMARY Method (400) and control unit (300) in a vehicle (100), for positioning a vehicle (100) with a roof mounted pantograph (130) laterally in relation to an energy transfer segment (120) above the vehicle (100). The method (400) comprises detecting (401) the energy transfer segment (120); defining (402) a left lateral sway limit (140) on the left side of the pantograph (130) and a right lateral sway limit (150) on the right side of the pantograph (130), in the driving direction (105) of the vehicle (100); determining (403) lateral position of the energy transfer segment (120) in relation to the defined (402) lateral sway limits (140, 150); and indicating (404) to the driver when the determined (403) lateral position of the energy transfer segment (120) is not within said lateral sway limits (140, 150).

Description

METHOD AND CONTROL UNIT FOR POSITIONING A VEHICLE TECHNICAL FIELD This document discloses a method and a control unit. More particularly, a method and a control unit is described, for positioning a vehicle with a roof mounted pantograph laterally in relation to an energy transfer segment above the vehicle.

BACKGROUND One way of transfer power to a vehicle with electrical propulsion system such as e.g. a Plug-in Hybrid Electric Vehicle (PHEV), a Plug-in Hybrid Vehicle (PHV), a plug-in hybrid or a Battery Electric Vehicle (BEV) may be to use a roof mounted pantograph similar to electrical trains. The power transfer could be static and / or dynamic, i.e., at standstill or during driving. Thereby various attractive advantages are reached such as less pollution, reduced noise from the vehicle, reduced operating costs, and time gain during travel (as no stop has to be made for filling up fuel), in comparison with vehicles with internal combustion engines.

The vehicle with the electrical propulsion system may comprise rechargeable batteries, or another energy storage device, that can be restored to full charge by connecting the roof mounted pantograph to a positive overhead contact wire and a negative overhead contact wire, respectively. Further, an electrical motor in the vehicle may be driven by the electricity stored in the batteries. In a hybrid vehicle, also an internal combustion engine is comprised. Thereby, the problem of range anxiety associated with all-electric vehicles may be reduced, as the combustion engine works as a backup when the batteries are depleted.

In some vehicles with an electrical propulsion system such as some trolleybuses, there may sometimes not be any energy storage device. Instead the electrical motor in the vehicle may be driven directly by the electricity provided by the overhead contact wires via the roof mounted pantograph.

The herein discussed vehicle may comprise e.g. a truck, a bus, a van, a car, a motorcycle, military vehicles, a trolleybus, a trolleytruck or any other similar type of vehicle not running on rails.

A difference between vehicles on rails such as electrical trains, and the herein discussed vehicles not running on rails is that electrical trains do not have any lateral movement between pantograph and the overhead contact wires as trains runs on rails as opposed to road vehicles where the driver may deviate laterally from the overhead contact wires when turning the steering wheel.

An inadvertent driver may not pay attention to the contact wires and thus the pantograph could lose contact with the contact wires and the power transfer is interrupted. Darkness, rain, fog, pollution, snow, sunlight etc. may make it difficult for the driver to visually see the contact wires and / or any road markings. Further, it is preferable that the driver focus his / her attention to the surrounding traffic situation, rather than scanning up in the air for finding the contact wires, which may cause an accident due to inattention and / or may become an ergonomic issue for the driver. Frequent head tilting may trigger torticollis, or any other dystonic condition, which may force the driver to instantly stop the vehicle and refrain from further driving for a considerable time.

In case the pantograph lose contact with the contact wires, the batteries of the vehicle will not charge, which may cause that the vehicle’s batteries may not be sufficiently charged to able to reach a subsequent area with contact wires for charging the batteries.

In case the vehicle lacks batteries, the vehicle will suddenly stop if the contact between the overhead contact wires and the pantograph is broken, which may cause an accident if the driver of a close behind vehicle is not attentive. Further, a traffic congestion may result during the time it will take to somehow tow the vehicle back in position for establishing contact with the contact wires.

In some prior art solutions, a sensor on the pantograph, or on the roof of the vehicle may measure the magnetic field generated by the contact wires. Further, a recommendation may be generated and displayed for the driver for placing the vehicle in optimal position.

However, it may be an advantage, or even necessary for the vehicle to not always be situated laterally centred under the contact wires, for example during cornering and / or when cutting a curve. In case the vehicle is e.g. a city bus driving in rush hour there are often standing passengers on-board. If the pantograph is kept in the middle of the contact wires under all circumstances during a turn there is a risk of uncomfortable lateral movements which may cause standing passengers to fall. When the vehicle is a truck, corresponding problems may occur with any cargo on-board. In the described prior art solution, numerous warnings would be generated in such situation, which may disturb and irritate the driver unnecessarily, to a degree that traffic safety may be hazarded.

Another problem is that such prior art solutions based on magnetic field measurements only can detect the current situation, not predict any future displacements of the contact wires/ road, for example in a curve.

The concept of providing electricity via overhead contact wires for the propulsion of vehicles is known since very long time (end of the nineteenth century).

However, despite the numerous advantages with the technology concept per se, and the rather long time of technological development within the field, large scale implementation of road vehicles with roof mounted pantographs has failed to materialise.

It thus appear that in order for reaching a practical implementation of vehicles with electrical propulsion system with roof mounted pantographs, further development is required, providing a solution to the above discussed problems.

SUMMARY It is therefore an object of this invention to solve at least some of the above problems and improve lateral positioning of a vehicle with a roof mounted pantograph.

According to a first aspect of the invention, this objective is achieved by a method in a vehicle, for positioning a vehicle with a roof mounted pantograph laterally in relation to an energy transfer segment above the vehicle. The method comprises detecting the energy transfer segment. Further the method comprises defining a left lateral sway limit on the left side of the roof mounted pantograph and a right lateral sway limit on the right side of the roof mounted pantograph, in the driving direction of the vehicle. In addition the method also comprises determining lateral position of the energy transfer segment in relation to the defined lateral sway limits. The method further comprises indicating to the driver of the vehicle when the determined lateral position of the energy transfer segment is within by said lateral sway limits.

According to a second aspect of the invention, this objective is achieved by a control unit in a vehicle. The control unit is configured for positioning a vehicle with a roof mounted pantograph laterally in relation to an energy transfer segment above the vehicle. The control unit is configured for detecting the energy transfer segment. Also, the control unit is configured for defining a left lateral sway limit on the left side of the roof mounted pantograph and a right lateral sway limit on the right side of the roof mounted pantograph, in the driving direction of the vehicle. The control unit in addition comprises determining lateral position of the energy transfer segment in relation to the defined lateral sway limits. Furthermore, the control unit also comprises indicating to the driver of the vehicle when the determined lateral position of the energy transfer segment is not within said lateral sway limits.

Hereby, thanks to the disclosed aspects, the driver is assisted in keeping the vehicle within the lateral sway limits to maintain electrical connection to the contact wires. Safety is increased since the driver could focus on the road ahead and the ambient traffic situation rather than looking up, searching for the contact wires. External projection in e.g. darkness and / or in case of snow or poor markings on the road may help the driver to find the lateral position when the contact wires and / or road markings are difficult to see.

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: Figure 1A illustrates a side view of a vehicle with a roof mounted pantograph; Figure 1B illustrates a vehicle with a roof mounted pantograph as seen from above; Figure 2 illustrates an above perspective overview of a scenario where a vehicle with a roof mounted pantograph is following overhead contact wires according to an embodiment of the invention; Figure 3A illustrates an example of lateral vehicle positioning according to an embodiment of the invention; Figure 3B illustrates an example of lateral vehicle positioning according to an embodiment of the invention; Figure 3C illustrates an example of lateral vehicle positioning according to an embodiment of the invention; Figure 3D illustrates an example of lateral vehicle positioning according to an embodiment of the invention; Figure 4 is a flow chart illustrating an embodiment of a 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 limited 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 description, considered in conjunction with the accompanying drawings. It 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 otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Figure 1A illustrates a scenario with a vehicle 100 driving in a driving direction 105. The vehicle 100 may comprise an energy storage device 110, such as e.g. rechargeable batteries, in some embodiments. The energy storage device 110, if any, may be charged by conductive electrical transmission from an overhead energy transfer segment 120 via a roof mounted pantograph 130.

The vehicle 100 may be e.g. a truck, a bus, a van, a car, a motorcycle, military vehicles, a trolleybus, a trolleytruck or any other similar type of vehicle not running on rails. The vehicle 100 may be configured for running on a road, in terrain or in water, for example.

The vehicle 100 may be driver controlled or driverless autonomously controlled vehicles in different embodiments. However, for enhanced clarity, the vehicle 100 is subsequently described as having a driver.

Thus the vehicle 100 may comprise an energy storage device 110 in some embodiments, which may be charged by the energy transfer segment 120 via the roof mounted pantograph 130. An electric motor in the vehicle 100 is then energised by the energy storage device 110.

However, in other embodiments, the vehicle 100 may not comprise any energy storage device 110. Instead the electric motor of the vehicle 100, e.g. an electric traction motor is energised by the overhead energy transfer segment 120 via a roof mounted pantograph 130.

An advantage with storing energy in the energy storage device 110 is that the vehicle 100 is not required to continuously be attached to the energy transfer segment 120.

An advantage with embodiments not having any energy storage device 110 is that weight and space is saved. Energy storage devices 110 may also be expensive and may have to be replaced after a certain time, which add costs.

A further advantage with vehicles 100 energised by the energy transfer segment 120 via the roof mounted pantograph 130, sometimes referred to as trolleybuses, is an impressive operational lifetime in comparison with combustion engine based vehicles. To mention an example thereof, about two thirds of the trolleybus fleet in Valparaiso (Chile) comprises trolleybuses built between 1946-1952, still in regular service; a fact that has helped the city to gain its designation by UNESCO as a World Heritage Site. Said trolleybuses have also collectively been declared a national monument by the Chilean government in 2003.

Nevertheless, some embodiments of the vehicle 100 may also comprise an additional combustion engine, which gives additional independence from the overhead energy transfer segment 120, allowing operation off-wire. By having an auxiliary power unit the vehicle 100 is allowed e.g. to get around a route blockage and / or may reduce the amount and / or complexity of overhead wiring needed e.g. at operating garages, depots, etc.

The energy transfer segment 120 is situated above a road or route of the vehicle 100 and may comprise e.g. two contact wires in some embodiments, one contact wire 121 with positive pole and one contact wire 122 with negative pole, extending in parallel with each other and with the road along at least a segment of the route of the vehicle 100. This differs from the corresponding energy transfer segment of a tram or electric train, which normally uses the track as the return part of the electrical path and therefore needs only one wire and one pole. However, other embodiments may comprise one contact wire 121, 122 above the vehicle 100 and one contact wire under, or at the side of the vehicle 100 in some alternative embodiments.

The roof mounted pantograph 130 thus may comprise e.g. two current collectors, or collector shoes as they also may be referred to as. One current collector may be dedicated to the contact wire 121 with positive pole and one current collector may be dedicated to the contact wire 122 with negative pole. This is further explained in conjunction with the presentation of Figure 1B.

Further, it may be mentioned that the vehicle 100 may have one or several pantographs 130. Further the pantograph 130 may have different designs in different embodiments, such as a symmetrical or diamond-shaped pantograph, a half-pantograph, a Z-shaped pantograph, trolley poles or any similar arrangement. The pantograph 130 may have either a single or a double arm in different embodiments. Further, the two current collectors may be kept jointly by one pantograph 130, or separate pantographs 130 may be used for each current collector in different embodiments.

The pantograph 130 may further be arranged to bring the one or two current collectors in contact with the respective contact wire 121, 122, e.g. by applying a substantially upward force on the current collectors, bringing them in contact with the contact wires 121, 122. Such upward force may be provided by pneumatic means, by hydraulic means, by a spring, by resilience of the material, by an electric motor, by a mechanical mechanism managed by the driver or similar. A sensor may be configured to measure the pressure force between the current collectors and the contact wires 121, 122 in some embodiments. A control and regulation system may, based on the sensor measurements assure that contact is maintained between the current collectors and the contact wires 121, 122, also during rough road conditions and bumpy passages, according to some embodiments.

According to some embodiments, a functionality is provided in order to assist the driver to keep the vehicle 100 within lateral sway limits. This will ensure power fed uninterrupted to the vehicle 100 by the energy transfer segment 120. The pantograph position relative the contact wires 121, 122 of the energy transfer segment 120 is determined by utilising e.g. a sensor and / or a camera in some embodiments.

Further, according to some embodiments, the system keeps track of the path forward of the energy transfer segment 120, i.e. the contact wires 121, 122 and the road to ensure comfortable and safe journey for the driver and the passengers (if any) in the vehicle 100 who may be standing in case of a city bus. If the system has knowledge about the path of the energy transfer segment 120 and the road ahead, the system may assist the driver in finding the optimal lateral position, which may not coincide with centring the pantograph 130 to the energy transfer segment 120, in e.g. a turn to make it more comfortable for the passengers and thereby avoiding accidents. The solution may also comprise side-way movement of the pantograph 130 relative the vehicle 100 in some embodiments. Thereby the vehicle 100 is enabled to further cut the corners a little for optimal passenger comfort when turning.

The path of the energy transfer segment 120 comprising the contact wires 121, 122 in the air, and the road path may be detected by suitable sensors such as e.g. a mono camera, a stereo camera, a laser scanner, an ultrasonic sensor, Global Positioning System (GPS) in combination with detailed GPS data, by receiving information from other vehicles (or a sensor on another vehicle) via wireless communication, by receiving information from a vehicle external sensor via wireless communication or a combination of at least two of the enumerated techniques for detecting the energy transfer segment 120.

Unless the driver intentionally leaves the path of the energy transfer segment 120, e.g. by flashing and turning, embodiments of the provided solution may work as follows.

In case the energy transfer segment 120, i.e. the contact wires 121, 122, is not enclosed within defined lateral sway limits, the driver is informed by e.g. by disclosing a sign or symbol at the instrument cluster, a Head Up Display (HUD), a sound or spoken message emitted via a load speaker, a vibration in the chair and / or the steering wheel of the vehicle 100, a torque assist in the steering wheel or similar notification.

Alternatively in some embodiments, an external projection may be made when the energy transfer segment 120 is not within the lateral sway limits. Such external projection may be made by e.g. laser, clever LED light or similar solution based on projection of visible light, which may be in particular advantageous in darkness or in poor visibility conditions. In some embodiments, an arrow or similar corresponding sign may be projected on the road surface in front of the vehicle 100 to inform the driver in which lateral direction the vehicle 100 should move to maintain contact with the energy transfer segment 120. Also information about a position to keep when turning the vehicle 100 coupled to the vehicle speed to maintain passenger comfort, in case the vehicle 100 comprises passengers. An escalation of warning could be done e.g. by changing colours and / or intensity of the projected light, and / or flashing the projected light. Alternatively the system may lit up lines on the track to indicate a recommended lateral position of the vehicle 100.

Thanks to the disclosed solution, the driver is assisted in keeping the vehicle 100 within the lateral sway limits to maintain electrical connection with the energy transfer segment 120. Safety is increased since the driver could focus on the road ahead and the ambient traffic situation rather than looking up at the contact wires 121, 122. External projection in e.g. darkness and / or in case of snow or poor markings on the road may help the driver to find the lateral position when the contact wires 121, 122 and / or road markings are difficult to see.

Figure 1B illustrates the vehicle 100 presented in Figure 1A, as perceived from an overhead view. The vehicle 100 is driving in the driving direction 105. The vehicle 100 may comprise the energy storage device 110, such as e.g. rechargeable batteries, in some embodiments. The energy storage device 110, if any, may be charged by conductive electrical transmission from the overhead energy transfer segment 120 via the roof mounted pantograph 130.

The energy transfer segment 120 is situated above a road or route of the vehicle 100 and may comprise one or two contact wires; e.g. one contact wire 121 with positive pole and one contact wire 122 with negative pole, extending in parallel with each other and with the road along at least a segment of the route of the vehicle 100.

The roof mounted pantograph 130 may comprise a first current collector 135-1, dedicated to the contact wire 121 with positive pole and a second current collector 135-2, dedicated to the contact wire 122 with negative pole in some embodiments. As may be noted from the illustration in Figure 1 B, the current collectors 135-1, 135-2 may have a certain lateral extension substantially perpendicular to the contact wires 121, 122.

Thereby, the driver is given a certain freedom to deviate laterally from having the current collectors 135-1, 135-2 centred vertically under the energy transfer segment 120. Thereby, lateral sway limits 140, 150 are created; i.e. a left lateral sway limit 140 on the left side of the roof mounted pantograph 130 and a right lateral sway limit 150 on the right side of the roof mounted pantograph 130, in the driving direction 105 of the vehicle 100. As long as the vehicle 100 is positioned with the energy transfer segment 120 i.e. the contact wires 121, 122 within the lateral sway limits 140, 150, electricity may be received by the current collectors 135-1, 135-2 from the respective associated contact wire 121, 122.

When the energy transfer segment 120 and / or any of the contact wires 121, 122 no longer is within the lateral sway limits 140, 150, an indication informing the driver thereof may be displayed in some embodiments. In some embodiments, the vehicle 100 may be positioned laterally such that the energy transfer segment 120 above the vehicle 100 is within the lateral sway limits 140, 150. In yet some embodiments, the roof mounted pantograph 130 may be laterally displaced in relation to the vehicle 100, for enclosing the energy transfer segment 120 above the vehicle 100 by the lateral sway limits 140, 150.

Figure 2 illustrates an overview example of a scenario wherein an embodiment of the previously presented vehicle 100 is driven along a road in the driving direction 105.

The road may have one consistent energy transfer segment 120 from the starting point to the final destination of the vehicle 100 in some embodiments. In other embodiments, the road may be provided with one or more distinct energy transfer segments 120, and the vehicle 100 may be driven either by stored electricity in the energy storage device 110 in the vehicle 100, or alternatively driven by an internal combustion engine in the vehicle 100, e.g. when the vehicle 100 is a PHEV, PHV or similar hybrid vehicle 100.

In some embodiments, electricity may be at least partly generated and provided to the energy transfer segment 120 by solar panels arranged at the road side for the multiple function of generating electricity, functioning as noise damping elements and / or wildlife fencing. Such solar panels may be opaque (for sparing the surroundings from the view of the traffic) or transparent (for enhancing the driver’s visual experience of the journey).

Figure 3A illustrates an example of how the previous scenario in Figure 2 may be perceived by the driver of the vehicle 100.

The vehicle 100 comprises a control unit 300 for positioning the vehicle 100 laterally in relation to the energy transfer segment 120 above the vehicle 100.

The vehicle 100 also comprises a sensor 310, such as e.g. a front camera directed upwards, arranged for detecting the energy transfer segment 120, i.e. the contact wires 121, 122.

Besides comprising a camera, the sensor 310 in some embodiments may comprise e.g. a stereo camera, a film camera, or similar device based on radar, infra-red light or micro waves for detecting the energy transfer segment 120.

The sensor 310 thus may detect the energy transfer segment 120 and a lateral position of the energy transfer segment 120 in relation to the lateral sway limits 140, 150 may be determined by the control unit 300, based on the detection made by the sensor 310.

Further, in the illustrated embodiment, information is displayed to the driver on a display 320, indicating that the energy transfer segment 120 is not within the lateral sway limits 140, 150, and that the vehicle 100 has to be moved 5 cm to the left in this arbitrary example, for the current collectors 135-1, 135-2 to connect to the respective contact wire 121, 122.

Figure 3B illustrates another example of how the previous scenario in Figure 2 may be perceived by the driver of the vehicle 100 according to another embodiment, alternative to the embodiment illustrated in Figure 3A.

The vehicle 100 comprises the control unit 300 for positioning the vehicle 100 laterally in relation to the energy transfer segment 120 above the vehicle 100, and possibly also the display 320. However, instead of detecting and determining the position of the energy transfer segment 120 by any sensor, the vehicle comprises a positioning device 340.

The positioning device 340 may be based on a satellite navigation system such as the Navigation Signal Timing and Ranging (Navstar) Global Positioning System (GPS), Differential GPS (DGPS), Galileo, GLONASS, or the like.

The geographical position of the positioning device 340, (and thereby also of the vehicle 100 and / or the pantograph 130) may be done continuously with a certain 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 350-1, 350-2, 350-3, 350-4. The satellites 350-1, 350-2, 350-3, 350-4 continuously transmit information about time and date (for example, in coded form), identity (which satellite 350-1, 350-2, 350-3, 350-4 which broadcasts), status, and where the satellite 350-1, 350-2, 350-3, 350-4 are situated at any given time. GPS satellites 350-1, 350-2, 350-3, 350-4 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 350-1, 350-2, 350-3, 350-4 distinguished from the others' information, based on a unique code for each respective satellite 350-1, 350-2, 350-3, 350-4. This information can then be transmitted to be received by the appropriately adapted positioning device 340 comprised in the vehicle 100.

Distance measurement can according to some embodiments comprise measuring the difference in the time it takes for each respective satellite signal transmitted by the respective satellites 350-1, 350-2, 350-3, 350-4, to reach the positioning device 340. As the radio signals travel at the speed of light, the distance to the respective satellite 350-1, 350-2, 350-3, 350-4 may be computed by measuring the signal propagation time.

The positions of the satellites 350-1, 350-2, 350-3, 350-4 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 mobile device 120 may be calculated by determining the distance to at least three satellites 350-1, 350-2, 350-3, 350-4 through triangulation. For determination of altitude, signals from four satellites 350-1, 350-2, 350-3, 350-4 may be used according to some embodiments.

Having determined the geographical position of the positioning device 340 (and thereby also of the vehicle 100 and / or the pantograph 130), it may be presented on a map, where the position of the vehicle 100 may be marked, as well as the positions of the energy transfer segment 120. In some embodiments, also a message, sign or other indication displayed on the display 320 may inform the driver in which direction and how much, to laterally move the vehicle 100.

Figure 3C illustrates yet another example of how the previous scenario in Figure 2 may be perceived by the driver of the vehicle 100 according to another embodiment, alternative to the embodiments illustrated in Figure 3A and Figure 3B respectively.

The vehicle 100 comprises the control unit 300 for positioning the vehicle 100 laterally in relation to the energy transfer segment 120 above the vehicle 100. However, instead of detecting and determining the position of the energy transfer segment 120 by any on-board sensor or by GPS positioning, the vehicle 100 comprises a receiver 370. The receiver 370 is configured to receive wireless signals from transmitters 360-1, 360-2, 360-3, which are external to the vehicle 100 and associated with the energy transfer segment 120, i.e. situated at predetermined (and thereby known) positions in relation to the energy transfer segment 120.

By receiving such wireless signals from e.g. three transmitters 360-1, 360-2, 360-3, direction and / or distance to the respective transmitter 360-1, 360-2, 360-3 may be determined and the lateral position of the energy transfer segment 120 in relation to the lateral sway limits 140, 150 may be determined by triangulation of the received wireless signals.

Any arbitrary radio signal and wavelength may be used for this purpose in different embodiments. However, as commonly known, the size of the receiver antenna at the receiver 370 is a function of the wavelength of the signal. Thus very long wavelengths (i.e. low frequencies) require very large antennas, which may become unfeasible.

Figure 3D again illustrates yet another example of how the previous scenario in Figure 2 may be perceived by the driver of the vehicle 100 according to another embodiment, alternative to the embodiments illustrated in Figure 3A, Figure 3B and / or Figure 3C respectively.

The vehicle 100 comprises the control unit 300 for positioning the vehicle 100 laterally in relation to the energy transfer segment 120 above the vehicle 100. Further, the vehicle 100 comprises the receiver 370. The receiver 370 is configured to receive wireless signals from a transmitter 390, external to the vehicle 100, which transmitter 390 in turn is in communicative connection with a camera 395, external to the vehicle 100.

The camera 395 may be situated in association with the energy transfer segment 120, such as for example at a predetermined position and / or distance in relation to the energy transfer segment 120, and directed towards the position of the vehicle 100, the pantograph 130 and / or the current collectors 135-1, 135-2. Information representing an image, or a sequence of images may then be transmitted wirelessly via the transmitter 390 to be received by the receiver 370 in the vehicle 100.

The wireless signal 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), or infrared transmission to name but a few possible examples of wireless communications.

The control unit 300, when receiving the information from the external camera 395, may determine the lateral position of the energy transfer segment 120 in relation to the lateral sway limits 140, 150, based on information received from the vehicle external camera 395 via wireless signals, and knowledge of the position of the external camera 395 in relation to the energy transfer segment 120.

Figure 4 illustrates an example of a method 400 according to an embodiment. The flow chart in Figure 4 shows the method 400 for use in a vehicle 100, for positioning a vehicle 100 with a roof mounted pantograph 130 laterally in relation to an energy transfer segment 120 above the vehicle 100.

The energy transfer segment 120 may in some embodiments comprise a first contact wire 121 with positive pole and a therewith parallel second contact wire 122 with negative pole. In other embodiments, energy transfer segment 120 may comprise a first contact wire while the second contact wire is situated under the vehicle 100, or possibly at the side of the vehicle 100.

The roof mounted pantograph 130 may comprise, or be attached to a first current collector 135-1, dedicated for contact with the contact wire 121 with positive pole and a second current collector 135-2, dedicated for contact with the contact wire 122 with negative pole in some embodiments.

The vehicle 100 may be any arbitrary kind of means for conveyance, such as a truck, a bus, a car, a motorcycle or similar. However, in some particular embodiments, the vehicle 100 may be a vehicle comprising passengers, such as a bus, an ambulance, an Armoured Personnel Carrier (APC) (or other military vehicle), a fire truck etc.

In order to correctly be able to position the vehicle 100, the method 400 may comprise a number of steps 401-406. However, some of these steps 401-406 may be performed solely in some alternative embodiments, like e.g. step 405 or 406. Further, the described steps 401-406 may be performed in a somewhat different chronological order than the numbering suggests. Step 402 may be performed before step 401 for example in some embodiments. The method 400 may comprise the subsequent steps: Step 401 comprises detecting the energy transfer segment 120, i.e. the first contact wire 121 with positive pole and the therewith parallel second contact wire 122 with negative pole, according to some embodiments.

In some embodiments, the energy transfer segment 120 may be detected by using a vehicle mounted camera 310, a laser scanner, an ultrasonic sensor or similar detector on the vehicle 100.

The vehicle mounted camera 310 may be directed upwards and / or forwards in some embodiments, in or order to predict the position of the energy transfer segment 120.

In some further embodiments, the geographical position of the vehicle 100, and thereby also of the roof mounted pantograph 130 and its defined lateral sway limits 140, 150 may be determined by a positioning device 340. Further, the energy transfer segment 120 may be detected by retrieval of the position of the energy transfer segment 120 from a map stored in a memory 525.

The energy transfer segment 120 may in some embodiments be detected by receiving a wireless signal by a receiver 370 in the vehicle 100, which signal carry information concerning the geographical position of the energy transfer segment 120. The wireless signal may be transmitted by a transmitter 360-1, 360-2, 360-3 associated with the energy transfer segment 120, i.e. wherein the respective transmitter 360-1, 360-2, 360-3 is positioned at a predetermined position or relation to the energy transfer segment 120, in some embodiments.

In some embodiments, a vehicle external camera 395 may be situated in association with the energy transfer segment 120, i.e. wherein the vehicle external camera 395 is positioned at a predetermined position or relation to the energy transfer segment 120. By transmitting wireless signals via a transmitter 390, and receiving the transmitted wireless signals by a receiver 370 in the vehicle 100, the energy transfer segment 120 may be detected.

The mentioned wireless signals may be 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), or infrared transmission to name but a few possible examples of wireless communications.

Step 402 comprises defining a left lateral sway limit 140 on the left side of the roof mounted pantograph 130 and a right lateral sway limit 150 on the right side of the roof mounted pantograph 130, in the driving direction 105 of the vehicle 100.

The lateral sway limits 140, 150 are the limits in the lateral direction, where the current collectors 135-1, 135-2 discontinue contact with the respective contact wire 121, 122, on the left/ right side respectively, in the driving direction 105 of the vehicle 100, in some embodiments.

Step 403 comprises determining lateral position of the energy transfer segment 120 in relation to the defined 402 lateral sway limits 140, 150.

In some embodiments, the lateral position of the energy transfer segment 120 in relation to the defined 402 lateral sway limits 140, 150 may be determined based on information from the vehicle mounted camera 310, or other similar detector on the vehicle 100.

In some further embodiments, the lateral position of the energy transfer segment 120 in relation to the defined 402 lateral sway limits 140, 150 may be determined based on the geographical position of the vehicle 100 and thereby also of the roof mounted pantograph 130 and its defined lateral sway limits 140, 150, as determined by the positioning device 340, and also based on retrieval of the position of the energy transfer segment 120 from a map stored in a memory 525.

In some embodiments, the lateral position of the energy transfer segment 120 in relation to the defined 402 lateral sway limits 140, 150 may be determined based on receiving the wireless signal by the receiver 370 in the vehicle 100, which signal may carry information concerning the geographical position of the energy transfer segment 120. The respective transmitter 360-1, 360-2, 360-3 may have been positioned at predetermined positions or relation to the energy transfer segment 120, in some embodiments; and the lateral position of the energy transfer segment 120 may be determined by triangulation of the received wireless signals from the respective transmitters 360-1, 360-2, 360-3.

In some embodiments, the lateral position of the energy transfer segment 120 in relation to the defined 402 lateral sway limits 140, 150 may be determined based on information received from the vehicle external camera 395 via wireless signals.

Step 404 comprises indicating to the driver of the vehicle 100 when the determined 403 lateral position of the energy transfer segment 120 is not within said lateral sway limits 140, 150.

The indication given to the driver may e.g. comprise a direction, indicating which lateral sway limit 140, 150 has been exceeded by the energy transfer segment 120, and / or an arrow or similar, indicating in which direction (left/ right) the driver is to turn the vehicle 100 in order to again get contact between the current collectors 135-1, 135-2 and the contact wires 121, 122. In some embodiments, the lateral sway limits 140, 150 may be displayed, or a line for the driver to follow may be projected.

The direction indicated to the driver of the vehicle 100 may be displayed or indicated at any of e.g.: a display 320 visible to the driver, a head-up display, a pair of glasses, a pair of contact lenses, a transparent display configured for augmented reality integrated with the windshield of the vehicle 100, a visible projection on the road ahead of the vehicle 100 by Light-Emitting Diode, LED, head lights, projector 380 or laser, an audio signal and / or a haptic signal.

By indicating such driving guidance to the driver in any of the described manners, the driver can be informed about the location of the energy transfer segment 120 without having to turn or move the head away and look for the information, but may focus on the forward traffic situation. Thereby, traffic safety is enhanced.

However, in some embodiments, no indication may be displayed to the driver of the vehicle 100 when the determined 403 lateral position of the energy transfer segment 120 is not within said lateral sway limits 140, 150, when the vehicle 100 is turning in a curve. In other embodiments, no indication may be displayed when the vehicle 100 is turning and flashing, as it may indicate that the driver intentionally leaves the road associated with the energy transfer segment 120 and will continue driving using stored battery power, or alternatively switch to the back-up internal combustion engine, if any.

Thereby, the driver is enabled to cut a curve and temporarily deviate from the energy transfer segment 120 without triggering any indications and / or lateral positioning adjustments. Thereby a better comfort is provided, e.g. to passengers in a buss, which thereby are saved from being squeezed against the window in the vehicle due to centrifugal force. The driver is spared from being exposed to numerous warnings and / or indications that may distract him/ her unnecessarily. This embodiment may be advantageous when the vehicle 100 comprises a battery and is able to deviate from the energy transfer segment 120 at least temporarily.

Step 405 may be performed only in some alternative embodiments, for example in case there is no driver present at the vehicle 100, or when the driver does not react on the indication displayed 404 to the driver. The optional step 405 thus may comprise positioning the vehicle 100 laterally such that the energy transfer segment 120 above the vehicle 100 is within the defined 402 lateral sway limits 140, 150, autonomously.

In some embodiments, a control signal may be generated by the control unit 300, for turning the steering wheel of the vehicle 100 for bringing the current collectors 135-1, 135-2 in contact with the respective contact wire 121, 122, on the left/ right side respectively, in the driving direction 105 of the vehicle 100. Thereby, the energy transfer segment 120 above the vehicle 100 becomes within the defined 402 lateral sway limits 140, 150.

It could thereby be avoided that the vehicle 100 lose contact with the energy transfer segment 120, also when the vehicle 100 is autonomous. In a vehicle 100 having a driver, the driver is able to focus on other issues such as the traffic situation etc.

Step 406 may be performed only in some alternative embodiments, for example in case there is no driver present at the vehicle 100, or when the driver does not react on the indication displayed 404 to the driver. The optional step 405 thus may comprise displacing the roof mounted pantograph 130 laterally in relation to the vehicle 100 for enclosing the energy transfer segment 120 above the vehicle 100 by the defined 402 lateral sway limits 140, 150.

Thus, the roof of the vehicle 100 may comprise a rail or similar arrangement, orthogonal to the driving direction 105 of the vehicle 100, on which the pantograph 130 is arranged for being displaced laterally by e.g. pneumatic means, by an electric motor or similar. A control signal may be generated by the control unit 300, for moving the pantograph 130 laterally on the rail or similar arrangement, to the left/ right side respectively, the required distance in order to bring the current collectors 135-1, 135-2 in contact with the respective contact wire 121, 122, in the driving direction 105 of the vehicle 100. Thereby, the energy transfer segment 120 above the vehicle 100 becomes within the defined 402 lateral sway limits 140, 150.

It is thereby possible to extend the lateral limits 140, 150 one at the time, e.g. in a curve, or in order to avoid an obstacle on the road, for example pass an immobile vehicle.

Figure 5 illustrates an embodiment of a system 500 for assisting a vehicle 100 with a roof mounted pantograph 130 to positioning the vehicle 100 laterally in relation to an energy transfer segment 120 above the vehicle 100. The system 500 comprises an infrastructure for providing electricity to the vehicle 100, comprising the energy transfer segment 120 arranged above the road so that vehicles may pass under it. The energy transfer segment 120, which may comprise a first contact wire 121 with positive pole and a therewith parallel second contact wire 122 with negative pole in some embodiments. The energy transfer segment 120 is electrically supported by electricity from an electricity network. The energy transfer segment 120 may be supported and upheld by poles at the roadside, or similar arrangement. The system also comprises the vehicle 100 with the roof mounted pantograph 130. The roof mounted pantograph 130 in turn comprises, or is attached to a first current collector 135-1, dedicated for contact with the contact wire 121 with positive pole and a second current collector 135-2, dedicated for contact with the contact wire 122 with negative pole, in some embodiments.

The system 500 also comprises a control unit 300 in the vehicle 100. The control unit 300 is configured for positioning a vehicle 100 with a roof mounted pantograph 130 laterally in relation to an energy transfer segment 120 above the vehicle 100, which may comprise a first contact wire 121 with positive pole and a therewith parallel second contact wire 122 with negative pole in some embodiments. The control unit 300 may perform at least some of the previously described steps 401-406 according to the method 400 described above and illustrated in Figure 4.

The control unit 300 is configured for detecting the energy transfer segment 120. Further, the control unit 300 is also configured for defining a left lateral sway limit 140 on the left side of the roof mounted pantograph 130 and a right lateral sway limit 150 on the right side of the roof mounted pantograph 130, in the driving direction 105 of the vehicle 100. Further, the control unit 300 in addition is configured for determining lateral position of the energy transfer segment 120 in relation to the defined lateral sway limits 140, 150. The control unit 300 is also configured for indicating to the driver of the vehicle 100 when the determined lateral position of the energy transfer segment 120 is not within said lateral sway limits 140, 150.

In some embodiments, the control unit 300 may furthermore be optionally configured for generating control signals for performing the recommended action autonomously, e.g. in case the vehicle 100 does not have any driver, or in case the driver does not follow the recommended action. Such recommended action may comprise positioning the vehicle 100 laterally such that the energy transfer segment 120 above the vehicle 100 is within the defined lateral sway limits 140, 150. Such recommended action may further comprise displacing the roof mounted pantograph 130 laterally in relation to the vehicle 100 such that the energy transfer segment 120 above the vehicle 100 again is within the defined 402 lateral sway limits 140, 150.

The control unit 300 may comprise a processor 520 configured for performing at least some of the previously described steps 401-406 according to the method 400, in some embodiments.

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.

The control unit 300 may further comprise a receiving circuit 510 configured for receiving a signal from a sensor 310, a positioning device 340 and / or a receiver 370 in the vehicle 100, for detecting the energy transfer segment 120, i.e. indicating presence of the one or more contact wires 121, 122 in different embodiments.

Furthermore, the control unit 300 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 embodiments, 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. ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), etc. in different embodiments.

Further, the control unit 300 may comprise a signal transmitter 530. The signal transmitter 530 may be configured for transmitting a control signal to be received by a display device 320; or by a steering wheel in some embodiments.

The previously described steps 401-406 to be performed in the control unit 300 may be implemented through the one or more processors 520 within the control unit 300, together with computer program product for performing at least some of the functions of the steps 401-406. Thus a computer program product, comprising instructions for performing the steps 401-406 in the control unit 300 may perform the method 400 comprising at least some of the steps 401-406 for positioning the vehicle 100 with the roof mounted pantograph 130 laterally in relation to the energy transfer segment 120 above the vehicle 100, when the computer program is loaded into the one or more processors 520 of the control unit 300.

Further, some embodiments may comprise a vehicle 100, comprising the control unit 300, configured for positioning the vehicle 100 laterally in relation to the energy transfer segment 120 above the vehicle 100, according to at least some of the steps 401-406.

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 401-406 according to some embodiments when being loaded into the one or more processors 520 of the control unit 300. The data carrier may be, e.g., a hard disk, a CD ROM disc, a memory stick, an optical storage device, a magnetic storage device or any other appropriate medium such as a disk or tape that may hold machine readable data in a nontransitory manner. The computer program product may furthermore be provided as computer program code on a server and downloaded to the control unit 300 remotely, e.g., over an Internet or an intranet connection.

The terminology used in the description of the embodiments as illustrated in the accompanying drawings is not intended to be limiting of the described method 400; the control unit 300; the computer program and / or the vehicle 100. Various changes, substitutions and / or alterations may be made, without departing from invention embodiments as defined 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 mathematical OR, i.e., as an inclusive disjunction; not as a mathematical exclusive OR (XOR), unless expressly stated otherwise. In 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. It will be further understood that the terms "includes", "comprises", "including" and / or "comprising", specifies the presence of stated features, actions, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, actions, integers, steps, operations, elements, components, and / or groups thereof. A single unit such as e.g. a processor may fulfil 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/ distributed on a suitable medium, such as an optical storage medium or a solidstate medium supplied together with or as part of other hardware, but may also be distributed in other forms such as via Internet or other wired or wireless communication system.

Claims

PATENT CLAIMS

1. A method (400) for positioning a vehicle (100) with a roof mounted pantograph (130) laterally in relation to an energy transfer segment (120) above the vehicle (100), which method (400) comprises: detecting (401) the energy transfer segment (120); defining (402) a left lateral sway limit (140) on the left side of the roof mounted pantograph (130) and a right lateral sway limit (150) on the right side of the roof mounted pantograph (130), in the driving direction (105) of the vehicle (100); determining (403) lateral position of the energy transfer segment (120) in relation to the defined (402) lateral sway limits (140, 150); and indicating (404) to the driver of the vehicle (100) when the determined (403) lateral position of the energy transfer segment (120) is not within said lateral sway limits (140, 150), and informing about a position to keep when turning the vehicle (100), coupled to the vehicle speed, to maintain passenger comfort.

2. The method (400) according to claim 1, further comprising: positioning (405) the vehicle (100) laterally such that the energy transfer segment (120) above the vehicle (100) is within the defined (402) lateral sway limits (140, 150).

3. The method (400) according to any of claims 1 or 2, wherein the energy transfer segment (120) is detected (401) by using a vehicle mounted camera (310), a laser scanner, an ultrasonic sensor or similar detector on the vehicle (100).

4. The method (400) according to any of claims 1 -3, further comprising determining the geographical position of the vehicle (100), and thereby also of the roof mounted pantograph (130) and its defined (402) lateral sway limits (140, 150), by a positioning device (340), and wherein the energy transfer segment (120) is detected (401) by retrieval of the position of the energy transfer segment (120) from a map stored in a memory (525).

5. The method (400) according to any of claims 1-4, wherein the energy transfer segment (120) are indicated by a transmitter (360-1, 360-2, 360-3) associated with the energy transfer segment (120), and detected (401) by a receiver (370) in the vehicle (100), which also determine (403) lateral position of the energy transfer segment (120) in relation to the defined (402) lateral sway limits (140, 150) by triangulation of received wireless signals.

6. The method (400) according to any of claims 1-5, wherein a vehicle external camera (395) is situated in association with the energy transfer segment (120), which is transmitting wireless signals to a receiver (370) in the vehicle (100), and wherein the lateral position of the energy transfer segment (120) in relation to the defined (402) lateral sway limits (140, 150) is determined (403) based on information received from the vehicle external camera (395) via wireless signals.

7. The method (400) according to any of claims 1-6, wherein the indication (404) to the driver comprises a direction, indicating a lateral direction to turn the vehicle 100 in order to enclose the energy transfer segment (120) by the lateral sway limits (140, 150).

8. The method (400) according to claim 7, wherein the direction indicated (404) to the driver of the vehicle (100) at any of: a display (320) visible to the driver, a head-up display, a pair of glasses, a pair of contact lenses, a transparent display configured for augmented reality integrated with the windshield of the vehicle (100), a visible projection on the road ahead of the vehicle (100) by Light-Emitting Diode, LED, head lights, projector (380) or laser, an audio signal, a haptic signal.

9. The method (400) according to any of claims 1-8, wherein no indication (404) is displayed to the driver of the vehicle (100) when the determined (403) lateral position of the energy transfer segment (120) is not within said lateral sway limits (140, 150), when the vehicle (100) is turning in a curve.

10. The method (400) according to any of claims 1-9, further comprising, in case the energy transfer segment (120) above the vehicle 100 is not within the lateral sway limits (140, 150), displacing (406) the roof mounted pantograph (130) laterally in relation to the vehicle (100) such that the energy transfer segment (120) above the vehicle (100) again is within the defined (402) lateral sway limits (140, 150).

11. A control unit (300) for positioning a vehicle (100) with a roof mounted pantograph (130) laterally in relation to an energy transfer segment (120) above the vehicle (100), wherein the control unit (300) is configured for: detecting the energy transfer segment (120); defining a left lateral sway limit (140) on the left side of the roof mounted pantograph (130) and a right lateral sway limit (150) on the right side of the roof mounted pantograph (130), in the driving direction (105) of the vehicle (100); determining lateral position of the energy transfer segment (120) in relation to the defined lateral sway limits (140, 150); indicating to the driver of the vehicle (100) when the determined lateral position of the energy transfer segment (120) is not within said lateral sway limits (140, 150); and informing about a position to keep when turning the vehicle (100), coupled to the vehicle speed, to maintain passenger comfort.

12. A computer program comprising program code for performing a method (400) according to any of claims 1-10 when the computer program is executed in a control unit (300) according to claim 11.

13. A vehicle (100) comprising a control unit (300) according to claim 11.