Patent Description:
In cities, there is a high risk of accidents involving cyclists. Accidents are usually caused by incorrect behavior on the part of cyclists, but also by other road users. Frequently, accidents occur in the case of incorrect or prohibited use of the road, errors in moving into the flow traffic, unadjusted speed, or incorrect behavior during turning.

The subject application therefore is concerned with an important aspect of a safety package for vulnerable road user vehicles, e.g. bicycles. According to this concept radio messages will be sent about the position, speed, direction and other parameters such as bicycle size, lean angle, acceleration of a cyclist to the local road users in the vicinity. These messages are processed by appropriately equipped surrounding vehicles and, in the event of a danger, lead to the driver being warned or the launch of an autonomous collision avoidance maneuver when autonomous driving technology is involved. These kind of systems are already known in the automotive sector.

From <CIT> a method of determining the current locomotion mode of a road user who is making use of a mobile telephone is known. Such method involves, that the place of the road user is successively determined on the basis of successive radiolocation instants. A vector chain of the locations as well as a vector sequence of the velocities of the mobile telephone is determined. Thereby a link of a respective place of the road user with a digital Road map, a so-called "map matching technique" is used to determine the way of locomotion of the road user.

From <CIT> a method for organizing traffic on the road is known which aims at minimizing road accidents. The position of vulnerable road users, particularly pedestrians or two-wheelers can be determined by means of the mobile phones of such road users. Core of the process according to the disclosure is that at least within an adjustable range, two traffic users moving in this range engage automatically in a direct intercommunication and inform each other about their locomotion. Through the direct and, above all, situation-based automatic intercommunication of the road users is the intermediate involvement of a control center to clear the situation superfluous. Valuable time is saved and automatic warnings as well as possible automatic interventions will be so promptly triggered, that causing an accident can be safely prevented.

From <CIT> an apparatus for determining the relative position between a first and a second vehicle is known. For determining a relative position between two vehicles the position data of the adjacent vehicles with certain metadata will be transferred to the other Vehicle. The transmission occurs for example by direct vehicle-to-vehicle communication or by way of a detour via a central station. The metadata can be used to make a selection of the available satellites for the position determination in the other vehicle. In this way, it is possible to minimize the systematic errors resulting from a different selection of the satellites in the two vehicles for the position determination with GPS signals as a result. In the inner city area, where the satellite signals are not always readily receivable, the signals from a direction sensor, distance sensor and steering wheel angle sensor for the position determination can also be evaluated.

From <CIT> an electric bicycle including a communication module and a computing device is known. The communication module receives vehicle information indicating a trajectory of a vehicle. The computing device compares the vehicle information to bicycle information, which represents a trajectory of the bicycle. The communication module wirelessly transmits the bicycle information to the vehicle associated with the vehicle information. A method includes generating an alert signal if the vehicle is predicted to collide with the bicycle.

From <CIT> systems and techniques relating to determining a real-time position of a mobile device are known. Such systems and techniques involve a data processing apparatus which includes: one or more integrated circuit (IC) device including a location processor configured to acquire and track measurements of location for a mobile wireless communication device; and a host processor programmed with a host software manager configured to obtain various positioning input signals from different device positioning technologies and assemble a selected set of the various positioning input signals into a unified format; wherein the data processing apparatus includes a hybrid fusion engine configured to receive data from the host software manager in the unified format and calculate a position of the mobile wireless communication device using the received data in accordance with input type information for the received data.

From <CIT> an approach is provided for generating location data error maps is known. The approach involves determining location data error information associated with at least one set of location data. The approach also involves causing, at least in part, an encoding of the location data error information as a function of a position parameter. The approach further involves causing, at least in part, a generation of at least one location data error map based, at least in part, on the encoding.

From <CIT> a mobile device is known, which is associated with a road vehicle or the like and which has a mapping or navigation functionality configured to determine whether the vehicle is in a forwards or backwards driving mode. When a change of driving mode is detected, the mapping functionality effectively resets so that the transition between driving modes is rendered smoothly and efficiently.

In view of the prior art mentioned above, there is still a problem that the position determination, which is solely based on satellite navigation is not precise enough for the purpose of a collision avoidance in connection with vulnerable road user vehicles. the precision of the position determined with GPS signals is announced to be ± <NUM>.

There is therefore a need for improving the position determination method in order to increase safety for vulnerable road users. This corresponds to the problem the invention is aiming to solve.

This object is achieved by a method for collision avoidance between a vulnerable road user vehicle and a surrounding vehicle according to claim <NUM>, a vulnerable road user vehicle according to claim <NUM>, and a computer program according to claim <NUM>.

The dependent claims include advantageous further developments and improvements of the invention as described below.

The solution is based on an adaptation of the vulnerable road user vehicle on one hand and, in particular the exact localization of the vulnerable road user vehicle through the interaction between the vulnerable road user vehicle and a portable device of the user of the vulnerable road user vehicle, such as smartphone or tablet
An advantage is that the solution works independently of the technology used for direct V2V or D2D communication (WLAN <NUM>. 11p, LTE-V, <NUM>).

First of all, it is mentioned that the vulnerable road user vehicle will be equipped with at least one odometer sensor supporting an independent position determination apart from the global navigation satellite system GNSS, such as Global Positioning System GPS, Globalnaja nawigazionnaja sputnikowaja sistema GLONASS, Galileo or Beidou. Moreover, the determination of a high precision position is done by interaction between the user vehicle and portable user equipment. This interaction comprises a step of transferring position detecting sensor data to said portable communication device. A wireless communication technology could be used for this data transfer, such as Bluetooth or ZigBee communication. In said portable communication device then there is executed a step of evaluating said received position detecting sensor data and deriving position data therefrom for the vulnerable road user vehicle. In particular for the position detecting sensor data in form of odometer sensor data a step of performing a map matching technique is performed for refining the position data. It follows a step of transferring the refined position data to the vulnerable road user vehicle and in the vulnerable road user vehicle a step of distributing the refined position data to the surrounding vehicles. The surrounding vehicles can hence make use of the received position data to estimate a trajectory for the vulnerable road user vehicle, determine the risk of a collision and finally take an action to avoid a collision. This solution has several important advantages. Normally, a vulnerable road user makes use of a portable communication device such as smart phone or tablet. These portable communication devices typically are equipped with a GPS module and offer the feature of satellite navigation. They also have enough CPU power to execute evolved algorithms. On the other hand, the user vehicle is better suited for participating in direct D2D or V2V communication. it is bigger in size than the portable communication device and can be equipped with multiple antennas at different places. The places for mounting the antennas can have better direct sight to the satellites of the satellite navigation system and also to other road participants. Also it is equipped with a high capacity battery and hence can deliver enough power for a prolonged direct D2D or V2V communication phase.

For improving safety of the user of the vulnerable road user vehicle, according to the claimed invention, a surrounding vehicle performs a step of calculating a trajectory for the vulnerable road user vehicle based on the position data received in the distribution step, determining the risk of a collision, and, if the risk of a collision exceeds a certain level, performing a collision avoidance maneuver and/or outputting a warning message to the driver of the surrounding vehicle. Such algorithms need to be installed in the vehicle anyhow if cooperative driving and/or autonomous driving shall be supported. Making autonomous collision avoidance maneuvers with the vulnerable road user vehicle is more difficult since the user is not at all protected.

An alternative solution which is also regarded as an embodiment of the invention is that not the bare position detection sensor data is transferred to the portable device, but the completed position data which is derived from the position detection sensor data. In this case, there is no need for performing the steps of evaluating the position detection sensor data and deriving the position data in the portable device.

Another advantage measure is if the vulnerable road user vehicle is equipped with at least two different position detection sensors and in the portable communication device a step of performing a data fusion algorithm with the position data derived from the received different position detecting sensors is performed. Both helps subjectively to improve the precision of the position determination.

For the communication between the vulnerable road user vehicle and the portable communication device.

in particular for the step of transferring the position detecting sensor data it is advantageous that it is performed by means of a short range wireless communication technique, such as Bluetooth or ZigBee. These communication systems are standardized and are readily available on the market and can be implemented without causing high costs. The user just needs to associate his portable communication device with the VRU vehicle before starting a route. This can be done automatically when a pairing has been established before.

For a vulnerable road user vehicle, such as bicycle, motorcycle, scooter, wheel chair, or roller, it is advantageous if it comprises at least two different position detecting sensors, a communication module and an antenna module.

It is further of advantage if said antenna module comprises at least two antennas for applying an antenna diversity technique such as MISO, corresponding to multiple input single output, SIMO, corresponding single input multiple output, or MIMO, corresponding to multiple input multiple output processing. When used in combination with diversity schemes, this improves the robustness of the communication against interferences.

Also advantageous for improving the exactness of the position determination is if the at least two position detection sensors comprise at least two of the sensors a wheel tick sensor, an inertial measurement unit, and an absolute positioning system module such as GPS, GLONASS, Galileo or Beidou.

Here, it is further advantageous that the communication module is capable to perform vehicle-to-vehicle communication V2V or device-to-device communication D2D according to one of the systems WLAN <NUM>. 11p corresponding to wireless LAN, LTE-V corresponding to Long Term Evolution-vehicle or <NUM> D2D corresponding to the <NUM>. Generation mobile communication technology. These technologies are also specified and can be implemented without subjective research and development work.

A corresponding computer program according to the invention, comprises program steps, which when run in a computer, carry out the steps of the portable communication device of any one of claims <NUM> to <NUM>.

This computer program is preferably implemented in the form of an app which could be installed on the portable device of the vulnerable road user, such as a smart phone or tablet computer as mentioned before.

It is further advantageous if the computer program further comprises program steps, which, when run in the computer, carry out a step of performing a data fusion algorithm with the position data derived from the different position detecting sensors. Such data fusion algorithm causes a high demand of computing time such that this type of calculation is better executed on the portable communication device which if it comes in the form of a smartphone or tablet is equipped with a powerful central processing unit CPU.

In this case, the absolute position data indicate the measured position of the vulnerable road user vehicle at a certain time in absolute values, for example in a UTM or WGS84 reference coordinate system. Optionally, the absolute position data may also be provided with an orientation, e.g. a current direction of movement of the vulnerable road user vehicle. A combination of position and orientation is often referred to as a pose. The position is usually expressed two-dimensionally in a Cartesian coordinate system.

The odometry position data, on the other hand, indicate a self-movement or relative movement of the vulnerable road user vehicle, for example in an arbitrarily defined reference coordinate system or in the so-called vehicle coordinate system ("body frame"). In this case, the self-movement, is indicated in each case relative to a preceding position of the vulnerable road user vehicle.

Corresponding advantages are apparent for a user according to the proposal and a computer program according to the proposal as claimed.

An exemplary embodiment of the invention is illustrated in the drawings and is explained in more detail below with reference to the figures.

Thus, for example, it will be appreciated by those skilled in the art that the diagrams presented herein represent conceptual views of illustrative circuitry embodying the principles of the disclosure.

The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. Moreover, explicit use of the term "processor" or "controller" should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, read only memory (ROM) for storing software, random access memory (RAM), and nonvolatile storage.

In the claims hereof, any element expressed as a means for performing a specified function is intended to encompass any way of performing that function including, for example, a) a combination of circuit elements that performs that function or b) software in any form, including, therefore, firmware, microcode or the like, combined with appropriate circuitry for executing that software to perform the function. The disclosure as defined by such claims resides in the fact that the functionalities provided by the various recited means are combined and brought together in the manner which the claims call for.

<FIG> shows a typical traffic situation where a vulnerable road user vehicle is involved. The vulnerable road user vehicle is exemplified as a bicycle and labelled with reference number <NUM>. A bicycle is only one example of a vulnerable road user vehicle. Other examples are a motorcycle, a scooter, a wheel chair, or a roller. The listing is not exhaustive and there exist further variants, e.g. a Segway Personal Transporter, or a Self-Balancing Unicycle and more.

Another vehicle is labeled with reference number <NUM>. That vehicle is a bigger size vehicle with <NUM>, <NUM> or more wheels. The term vehicle is to be understood as a collective term for motor vehicles with an internal combustion engine or an electric motor. Whether for passenger cars, trucks, buses, agricultural vehicles or construction machines. The list is not exhaustive and includes other vehicle categories.

For these types of vehicles there exist a plurality of communication techniques. Vehicles participate in mobile communication since long, and now with cooperative or autonomous driving technologies arising there is also a focus on vehicle direct communication, which is necessary for this purpose. Various systems for vehicle communication are developed. Examples include WLAN-based vehicle communication, also called "ad-hoc domain", and vehicle communication in the field of mobile radio networks. In the case of mobile radio-based technology, however, the base station has to transmit the messages from vehicle to vehicle. This is the area where communication takes place in the so-called "Infrastructure Domain". For the future mobile radio generation, the vehicle direct communication is also made possible. In LTE, according to Long Term Evolution, this variant is called LTE-V corresponding to LTE vehicle, and in the case of the <NUM> initiative this variant is often called D2D for device two device communication.

Such vehicles <NUM> are equipped with a communication module, which serves as a transmitting and receiving unit for communication in a mobile radio network. All messages from the vehicle <NUM> (uplink) and to the vehicle <NUM> (downlink) are routed either via a base station <NUM> which serves a mobile radio cell or, in the case of direct vehicle communication (Sidelink), directly between a plurality of the vehicles <NUM>. If the vehicles <NUM> are within this mobile radio cell, they are registered or logged in at the base station <NUM>. If they leave the mobile cell, they are handed over to the neighboring cell (handover) and accordingly logged out or logged off at the base station <NUM>. The base station <NUM> also provides access to the Internet so that the vehicles <NUM> or all other mobile radio subscribers are supplied with Internet data in the mobile radio cell.

Such mobile radio technologies are standardized and reference is made here to the corresponding specifications of mobile radio standards. As a modern example of a mobile radio standard, reference is made to the 3GPP initiative and the LTE standard (Long Term Evolution). Many of the related ETSI specifications are currently available in the version <NUM>. The following is mentioned as an example: ETSI TS <NUM><NUM> V13. <NUM> (<NUM>-<NUM>); Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures (3GPP TS <NUM> version <NUM>. <NUM> Release <NUM>).

<FIG> shows an example of a bicycle <NUM> which is enhanced with communication technology for the purpose of the proposal. The reference numbers shown in <FIG> denote an on-board communication unit <NUM>, two antennas <NUM> one mounted at the rear end of the bicycle and the other at the front of the bicycle, a wheel tick unit WTU <NUM>, a GPS module <NUM> and a battery <NUM>. In the example shown in <FIG>, the bicycle corresponds to an e-bike equipped with an electric motor <NUM>. The battery <NUM> therefore is rechargeable and the capacity of the battery <NUM> is big.

<FIG> now shows the block diagram of the communication system with which the bicycle <NUM> is equipped. Here, it is noted that the same components are labelled with the identical reference numbers which are also used in <FIG>. The wheel tick sensor <NUM> just delivers information about the rotational movement of the bicycle wheels. This provides information about the distance the bicycle has moved starting from a reference point. An inertial measurement unit <NUM> works by detecting the acceleration using one or more accelerometers and rotational rate using one or more gyroscopes. For motorbikes there exist IMUs which are readily available and could also be used in bicycles. They basically measure acceleration in longitudinal and lateral direction, but also the lean angle of the bike is measured. There exist IMUs which measure <NUM> degrees of freedom. To further add precision a 3D compass to the IMU could be integrate to add another <NUM> degrees of freedom. This type of information is primarily used for the purpose of electronic traction control. The GPS module <NUM> delivers an absolute position with satellite navigation as explained above.

The on-board unit <NUM> is a communication module which comprises a WLAN module or an LTE modem as indicated above.

In the following it is assumed that the on-board unit <NUM> comprises an LTE modem. This LTE modem is compliant with the specification for direct vehicle two vehicle communication LTE-V as above mentioned. This sort of direct V2V communication makes use of the sidelink communication direction as specified in the various LTE specifications. The on-board unit <NUM> may also be equipped with a Bluetooth communication protocol stack such that the module is capable to exchange messages with an associated Bluetooth partner station.

The method for collision avoidance is now described with the help of <FIG>.

At the beginning, the cyclist connects his mobile phone to the bicycle <NUM> via Bluetooth communication. This corresponds to the well-known Bluetooth association process. Bicycle and smartphone can communicate continuously. In the following we describe the collision avoidance procedure:.

The bicycle measures a position using said GPS module <NUM>. This task is better performed at the bicycle <NUM> than at the portable communication device, since the bicycle may be equipped with better antennas having a better direct visual connection to the sky than what is possible with the portable device. Several antennas <NUM> for the mobile communication can also be installed on the bicycle <NUM> for making use of an antenna diversity technique, in particular reception diversity such as MISO technique corresponding to multiple input single output.

The bicycle <NUM> takes information about the movement of the wheels by means of said wheel-tick unit <NUM>. This can only be done on the bicycle <NUM> with a sensor - this is not possible on the portable communication device. Moreover, the bicycle <NUM> receives information about the movement and orientation / inclination via said inertia! Measurement Unit (IMU) <NUM> and GPS data from the GPS module <NUM>. The bicycle <NUM> transmits the recorded data to the portable communication device. All this happens in step <NUM> of <FIG>.

The smart phone evaluates the position sensor data and calculates position data for the bicycle in steps <NUM> and <NUM>. The calculation is performed with the recorded raw data that had been collected in step <NUM>. The way the smartphone calculates the bicycle position is basically a known process. smartphones and tablets are anyway capable to calculate the absolute position of the smartphone, since they are usually equipped with a navigation app, like "Google Maps", a trademark from Google Inc. The calculation of the position is carried out in step <NUM>. Steps <NUM> and <NUM> are optional and will be left out if the GPS module delivers completed position data on its own.

The portable device performs a step of map matching in step <NUM> with the position data to improve the position quality. The map matching technique maps the measured position with the map information about the location and geometry of objects in the map so that the most likely position of the object is determined in the map. Also the map matching technique is used in conventional navigation systems, such that it is referred to such state of the art solutions for further details.

The different sensor systems, odometry with WTS and IMU sensor and GPS deliver different results for the bicycle position. Both position results are subject to errors. In step <NUM> then the technique of data fusion is applied on the different position data. This technique is capable of merging the different position results. With this technique the precision of the position determination is subjectively increased. Also the data fusion technique, sometimes also called "sensor fusion" is known in the state of the art. Applicant refers to the former application of the applicant with application number <CIT> for further details about the data fusion technique.

The map matching technique requires that map data is updated frequently to perform this step with high precision. The data fusion technique comprises a high demand of calculation expenditure. Therefore, these steps should be better performed on the portable device than on bicycle <NUM>.

The finished position is sent back to the bicycle <NUM> in step <NUM>.

The bike distributes information on the finished position (see above) and dimensions of the bicycle <NUM> to all road users in step <NUM>. This is implemented using one of the possible communication technologies that allow direct communication with the environment (<NUM>. 11p, LTE-V, future <NUM> D2D technology). The distribution of that information can be done significantly better than with the portable device: As above mentioned, it can be equipped with better antennas for the V2V, D2D or car2car direct communication. Furthermore, the continuous emission of signals also requires energy. This can be provided on the bicycle more easily than on the portable device.

The surrounding vehicles which receive the bicycle <NUM> position information use it to calculate on their own the bicycle trajectory. The trajectory describes the bicycle movement in a certain time period which typically also comprises a time period in the future such that the vehicle <NUM> has an estimate of where the bicycle <NUM> will go in order to be able to estimate the a risk of a collision. The bike trajectory is predicted in step <NUM> and the risk of a collision is calculated in step <NUM>. If vehicle <NUM> recognizes a certain risk of a collision, it outputs a warning message to the driver. An alternative embodiment of the solution is that the vehicle automatically performs a collision avoidance maneuver without waiting for the reaction of the driver. Here, the vehicle could perform a strong braking action or an emergency braking action in order to avoid a collision with the bicycle.

A good overview about different ways to calculate such collision avoiding maneuver is described in a thesis report of <NPL>. Another detailed example of such a system is described in the pending application of the applicant with the number <CIT>.

It is to be understood that the proposed method and apparatus may be implemented in various forms of hardware, software, firmware, special purpose processors, or a combination thereof. Special purpose processors may include application specific integrated circuits (ASICs), reduced instruction set computers (RISCs) and/or field programmable gate arrays (FPGAs). Preferably, the proposed method and apparatus is implemented as a combination of hardware and software. Moreover, the software is preferably implemented as an application program tangibly embodied on a program storage device. The application program may be uploaded to, and executed by, a machine comprising any suitable architecture. Preferably, the machine is implemented on a computer platform having hardware such as one or more central processing units (CPU), a random access memory (RAM), and input/output (I/O) interface(s). The computer platform also includes an operating system and microinstruction code. The various processes and functions described herein may either be part of the microinstruction code or part of the application program (or a combination thereof), which is executed via the operating system. In addition, various other peripheral devices may be connected to the computer platform such as an additional data storage device and a printing device.

It should be understood that the elements shown in the figures may be implemented in various forms of hardware, software or combinations thereof. Preferably, these elements are implemented in a combination of hardware and software on one or more appropriately programmed general-purpose devices, which may include a processor, memory and input/output interfaces. Herein, the phrase "coupled" is defined to mean directly connected to or indirectly connected with through one or more intermediate components. Such intermediate components may include both hardware and software based components.

Claim 1:
A method for collision avoidance between a vulnerable road user vehicle (<NUM>) and a surrounding vehicle (<NUM>), wherein the user of the vulnerable road user vehicle (<NUM>) makes use of a portable communication device, the method comprising the steps of:
- in said vulnerable road user vehicle, transferring (<NUM>) position detecting sensor data or position data derived therefrom to said portable communication device,
- in said portable communication device, evaluating (<NUM>) said position detecting sensor data and deriving (<NUM>) position data for the vulnerable road user vehicle (<NUM>) in case position detecting sensor data are transferred (<NUM>) to the portable communication device, performing (<NUM>) a map matching technique for refining the position data, and transferring (<NUM>) the refined position data to the vulnerable road user vehicle (<NUM>),
- in the vulnerable road user vehicle (<NUM>), distributing (<NUM>) the refined position data to the surrounding vehicle (<NUM>), and
- in the surrounding vehicle (<NUM>), predicting (<NUM>) a trajectory for the vulnerable road user vehicle (<NUM>) based on the position data received in the distribution step (<NUM>), determining (<NUM>) a risk of a collision, and, if the risk of a collision exceeds a certain level performing a collision avoidance maneuver and/or outputting (<NUM>) a warning message to the driver of the surrounding vehicle (<NUM>).