Systems and methods to create accurate digital models of driving surface boundary limits

Abstract

A method and system for generating a digital boundary model representing a pre-established boundary 105 of a physical driving surface 104 comprising: receiving positional data for each of a plurality

Description

FIELD OF THE INVENTION

[0001] The present disclosure is concerned with systems and methods for the creation of accurate digital models representing boundary limits on physical driving surfaces. More particularly, though not exclusively, the present disclosure is directed toward improvements in or relating to systems and methods for creating accurate digital representations of boundary limits on physical driving surfaces such as roadways, car parks and racetracks that cover significant geographical areas, where the digital representations of the boundary limits may be used to determine whether a physical (real) vehicle has exceeded or transgressed a real boundary or threshold of the physical driving surface. It is to be appreciated that whilst the present disclosure is primarily concerned with representation on driving surfaces, it is also envisaged that the disclosures may be equally applicable to the creation of digital representations of boundary limits of a surface for a multitude of purposes. BACKGROUND OF THE INVENTION

[0002] Ongoing developments in a variety of vehicle technologies over several years have increasingly necessitated the ability to automatically and accurately determine positions of vehicles on driving surfaces. One such example relates to autonomous (or semi-autonomous or automated) vehicle operation. In particular, when a vehicle is being driven autonomously, it is crucial to determine whether the vehicle is approaching or crossing a boundary (such as the edges of white or coloured lines that mark the driveable limits of a roadway or of lines that mark the boundaries between driving lanes or of lines that represent stopping limits at road junctions or of lines that delimit parking bays in a car park or any other marking on or feature of a driving surface). This determination is necessary so that corrective action can be automatically taken by the autonomous (or semi-autonomous or automated) vehicle, where necessary, to avoid the vehicle transgressing into the path of another vehicle in a separate lane or to avoid crashing into a physical obstacle. Due to the nature of an autonomous vehicle, it is advantageous for a computer-based methodology for the determination of boundary approach to be used. The determination is also advantageous for manually controlled vehicles as it may provide the basis for warnings to the driver.

[0003] Another such example relates to the field of motorsports. Typically, in motorsport events, the rules of the sport do not permit a vehicle to cross over a boundary edge of the track. If they should do so, a penalty is often imposed upon the relevant vehicle. In such events, the vehicles will be travelling at high velocities, and it can be difficult to determine visually, for example by the eye, whether the vehicle (or a portion of the vehicle) has crossed the boundary. It is particularly difficult to make such a determination in real time which can lead to disruption to the race or the application of a penalty for the transgression substantially after the infringing event has occurred. The use of a computer-based methodology can therefore be advantageous in such situations to overcome the inherent problems involved.

[0004] In each of the above examples, it is necessary to have the ability to accurately track the position of vehicles on the driving surface. However, it is also important to have the ability to determine the position of the relevant predetermined boundary limits of the driving surface respective to both the driving surface itself and the vehicles which are being tracked such that it can be determined when a vehicle has transgressed the boundary. Such boundary limits can be created in a digital space by the establishment of virtual models, which provide a representation of the position of the boundaries of the physical driving surface and the driving surface itself. Representations of tracked physical vehicles may then be created in the same digital space and compared to the created models to determine whether the vehicle is approaching or has crossed a boundary in physical reality.

[0005] Such a system necessitates that the real-world position of both the vehicles and the boundaries is determined to a high degree of accuracy to input into the model to ensure that any transgression of the boundaries is determined appropriately.

[0006] Regarding tracking of vehicle positions to a sufficient degree of accuracy to determine boundary transgression, Reference [1] (Yurtsever, E.; Lambert, J.; Carballo, A.; Takeda, K. A Survey of Autonomous Driving: Common Practices and Emerging Technologies. IEEE Access 2020, 8, 58443-58469) provides a recent survey of the state of the art in automated driving systems (ADSs) and clearly demonstrates by omission that the approach to infrastructure-based vehicle tracking disclosed in the Applicant’s prior patent applications (WO 2021 / 214496A and WO2022 / 003343A both of which are incorporated by reference) is novel.

[0007] Reference [2] (Reid, T.G.; Houts, S.E.; Cammarata, R.; Mills, G.; Agarwal, S.; Vora, A.; Pandey, G. Localization Requirements for Autonomous Vehicles. SAE Int. J. Connect. Autom. Veh. 2019, 2, 173-190) demonstrates that, in terms of emerging ADS technologies for road transport, any system that monitors the positions and movements of vehicles must have a lateral tracking accuracy better than 10cm in relation to road markings on the road surface that define traffic lanes and road edges, if a safety risk to passengers comparable with that in air and rail transport is to be assured. In motorsport the regulations for ‘track limits’ (Reference [3] - Motor Sports Association United Kingdom Regulations) require a similar precision in terms of the relation between the surface contact patch of vehicle tyres and the outer edges of the track limit lines marked on the circuit. The systems and methods for precise vehicle tracking in the Applicant’s prior patent applications (referenced above) provide the means to achieve and exceed these levels of vehicle tracking accuracy provided that digital models of the roadways and racetracks and their limits are available to a supporting level of accuracy, which needs to be an order of magnitude better than the vehicle tracking accuracy in order not to compromise the vehicle tracking precision. Hence, the boundary model accuracy compared to the real-world truth must be of the order of 10mm across its full scope. However, the establishment of levels of model accuracies in comparison to real-world truth can be susceptible to ‘circular logic’ or ‘self-fulfilment’ and hence, in order to avoid this pitfall, the determined boundary limit models will typically need to be a further order of magnitude more accurate again - namely in the order of 1 mm with respect to real-world truth.

[0008] Regarding the creation of boundary models with a sufficient degree of accuracy to determine boundary transgression, prior art systems have established methods for creating digital terrain models (DTMs) of roadways and vehicle racetracks that cover large geographical areas, using for example drone mounted Light Detection &Ranging (LIDAR) scanning equipment, drone mounted photogrammetry equipment, or satellite imaging. However, none of these can provide the sufficiently high accuracy that is required (as mentioned above) to create boundary models containing the information necessary for high accuracy tracking of vehicles in relation to the markings and boundaries on the roadways and racetracks on which they operate. Also, these approaches become uneconomic for the large geographical areas involved in road transport networks and large motor racing circuits, which can be many miles in circumference. It is to be noted that commonly accepted terminology defines a DTM as representing bare earth topography, void of surface features (vegetation, trees, buildings etc), which is the appropriate class of model fordriving surfaces.

[0009] It is an object of the present disclosure to overcome one or more of the problems described above. SUMMARY OF THE DISCLOSURE

[0010] According to a first aspect of the present embodiments, there is provided a method for generating a digital boundary model representing a pre-established boundary of a physical driving surface using a processing system, the method comprising: receiving positional data for each of a plurality of boundary points on the pre-established boundary, where the positional data of each of the plurality of boundary points comprises a relative position of the respective boundary point to a reference point on or proximate to the driving surface; generating a plurality of virtual splines using the received positional data, each virtual spline comprising a plurality of interpolated points positioned between two adjacent boundary points of the plurality of boundary points along the pre-established boundary; and composing the digital boundary model from the plurality of virtual splines, wherein the digital boundary model represents the pre-established boundary and comprises a polyline created by combining the plurality of generated spines and wherein each interpolated point of the polyline represents a boundary limit of the digital boundary model.

[0011] In an embodiment, each boundary point has a respective sequential number indicating the respective position of the boundary point along the pre-established boundary and the positional data of one of the boundary points comprises the sequential number of the boundary point.

[0012] In another embodiment, generating the plurality of virtual splines comprises: using the positional data of each boundary point to determine the relative positions of the boundary points; and assigning a respective sequential number to each boundary point indicating the respective position of the boundary point along the pre-established boundary.

[0013] Composing the digital boundary model may comprise using the sequential numbers of boundary points to combine the plurality of generated splines in a corresponding sequential order. This advantageously enables the order of the received data to be maintained for the construction of the digital boundary model.

[0014] In some embodiments, composing the digital boundary model comprises connecting a first one of the plurality of splines with a last one of the plurality of splines to create a closed polyline representing a looped pre-established boundary. This is particularly advantageous for boundary determination for racetracks which are in a loop.

[0015] In some embodiments, the positional data for each of the plurality of boundary points comprises information representative of the boundary point in two horizontal dimensions such as latitude and longitude and generating the plurality of virtual splines comprises generating a spline in two-dimensional coordinate space. This form of digital boundary model is useful where there are limits to computing power or a driving surface is generally flat thus not requiring much information of differences in altitude to be recorded.

[0016] In other embodiments, the positional data for each of the plurality of boundary points comprises information representative of the boundary point in three dimensions and generating the plurality of virtual splines comprises generating a spline in three-dimensional coordinate space. This enables variation in the height (altitude) of the driving surface and leads to a better digital boundary model.

[0017] In some embodiments, the positional data for each of the plurality of boundary points comprises geographical location information representative of the geographical location of the boundary point and the method further comprises providing the geographical location information to a modelling system to geographically locate the pre-established boundary in a virtual model of the physical driving surface.

[0018] Preferably, the method further comprises measuring positional data of the boundary points along the pre-established boundary; the measuring step comprising: establishing a reference point outside of or at the driving surface and placing a reference sensor at the reference point; locating one of the plurality of boundary points as a measurement point on the pre-established boundary and placing a boundary reflector at the measurement point; using the reference sensor and the boundary reflector to measure two relative orthogonal angles in 3D-coordinate space and a distance between the measurement point and the reference point; recording the two orthogonal angles and the distance between the measurement point and the reference point as the positional data of the measurement point.

[0019] The method may further comprise: moving the boundary reflector to another one of the plurality of boundary points along the pre-established boundary adjacent to the measurement point to establish a new measurement point.

[0020] The moving step may comprise moving the boundary reflector a first predetermined maximum distance (for example of 1.00 metres) along the pre-established boundary where the pre-established boundary comprises a substantially linear section between the measurement point and the new measurement point. This provides an optimum reduction of data whilst maintaining a high level of accuracy of the system.

[0021] The moving step may comprise moving the boundary reflector a second predetermined maximum (for example of 0.25 metres) along the pre-established boundary where the pre-established boundary comprises a substantially non-linear section (such as a curved section) between the measurement point and the new measurement point but where the predetermined maximum is such that the line between the two measurement points does not exceed an acceptable accuracy. Once again this reduces data generated whilst maintaining a high level of accuracy of the system. Preferably, the second predetermined maximum distance is less than the first predetermined maximum distance.

[0022] The method preferably further comprises repeating the using and recording steps with respect to the new measurement point to determine positional data for the new measurement point. This process can then be repeated multiple times to map the pre-existing boundary within a predetermined range from the reference point. The use of a predetermined range for measurement ensures accuracy of the measurement is within an acceptable accuracy tolerance.

[0023] The using step may comprise determining the distance between the reference point and the new measurement point is greater than a predetermined reference distance, and in this case the method further comprises: repositioning the reference sensor at a new reference point such that the distance between the new reference point and the new measurement point is less than the predetermined reference distance. In an embodiment, the using step comprises determining if the distance between the reference sensor and the boundary location is greater than 80.00 metres. Once again, this distance is chosen to ensure the right level of accuracy is maintained. In such a situation, the method may further comprise selecting a location of the new reference point to be within 80 metres of the reference point.

[0024] Preferably, the receiving step comprises receiving positional data for each of a plurality of boundary points on the edge of a racetrack. Clearly the application of the present disclosure to determining whether a race vehicle has exceeded track limits is highly advantageous and solves a long-felt desire to reliably determine this issue without undue expense.

[0025] In an alternative embodiment, the receiving step comprises receiving positional data for each of a plurality of boundary points on the edge of a starting grid marker of a racetrack. Here the present embodiments of the disclosure can be used to establish small discrete bounds for determining if a vehicle is not aligned with the stipulated starting position and so has transgressed a racing rule.

[0026] According to another aspect of the present disclosure, there is provided a system for generating a digital boundary model representing a pre-established boundary of a physical driving surface, the system comprising: a processing system configured to receive positional data for each of a plurality of boundary points on the pre-established boundary, where the positional data of each of the plurality of boundary points comprises a relative position of the respective boundary point to a reference point on or proximate to the driving surface; generate a plurality of virtual splines using the received positional data, each virtual spline comprising a plurality of interpolated points positioned between two adjacent boundary points of the plurality of boundary points along the pre-established boundary; and compose the digital boundary model from the plurality of virtual splines, wherein the digital boundary model represents the pre-established boundary and comprises a polyline created by combining the plurality of generated spines and wherein each interpolated point of the polyline represents a boundary limit of the digital boundary model.

[0027] The system may be further configured to measure positional data of the boundary points along the pre-established boundary; the system further comprising: a reference sensor placed at a reference point outside of or at the driving surface; a boundary reflector placed at a measurement point on the pre-established boundary; wherein the processing system is configured to use the reference sensor and the boundary reflector to measure two orthogonal angles within a 3D-coordinate system and a distance between the measurement point and the reference point; and to record the two orthogonal angles and the distance between the measurement point and the reference point as the positional data of the measurement point. The two orthogonal angles can be the azimuth and elevation in the spherical 3D-coordinate space.

[0028] In some embodiments, the reference sensor comprises a theodolite and a distance sensor incorporating an infrared laser.

[0029] The reference sensor may be configured to enable the horizontal levelling of the sensor. This is particularly useful to ensure higher accuracy results.

[0030] In some embodiments, the reference sensor comprises a wireless transmitter to transmit measurements made at the reference location to the processing system. This makes the process of recording the data for creating the digital boundary model far easier than a wired solution and typically speeds up the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order that the disclosure may be more readily understood, reference will now be made, by way of example, to the accompanying drawings in which: Figure 1 is a schematic block diagram of present embodiments illustrating an overview of the digital boundary model creation system; Figure 2A is a schematic block diagram illustrating the processing system of Figure 1 in greater detail; Figure 2B is a schematic block diagram illustrating the position sensing system of Figure 1 in greater detail; Figure 3 is a schematic isometric view of part of a racetrack illustrating a partial arrangement of the position sensing system of Figure 1 in a use scenario; Figure 4 is a schematic planar view of a racetrack illustrating an arrangement of locations of use of the position sensing system of Figure 1 in a use scenario; Figure 5 is a flow diagram illustrating a method of operation of the boundary model creation system of Figure 1; Figure 6A is a flow diagram illustrating a method of obtaining positional data operation for use with the boundary model creation system of Figure 1; Figure 6B is a flow diagram illustrating a further method of obtaining positional data operation for use with the boundary model creation system of Figure 1; Figure 7 is an image of a racetrack where the boundary model creation system of Figure 1 may be employed; Figure 8 is an isometric view of a racetrack illustrating a partial arrangement of the position sensing system of Figure 2B in an illustrative scenario; Figure 9 is an image of a curved portion of a racetrack where the boundary model creation system of Figure 1 may be employed in an illustrative scenario; Figure 10 is an image of a straight portion of a racetrack where the boundary model creation system of Figure 1 may be employed in an illustrative scenario and a portion of a generated polyline; Figure 11 is an image of a curved portion of a racetrack where the boundary model creation system of Figure 1 may be employed in an illustrative scenario and a portion of a generated polyline; Figure 12 is an image of portion of a racetrack with starting grid markers where the boundary model creation system of Figure 1 may be employed in an illustrative scenario and a generated polyline for a marker; Figure 13 is a top-down view of placement positions of the position sensing system of Figure 2B in an illustrative scenario; and Figure 14 is a top-down view of a generated polyline for a race circuit in an illustrative scenario. DETAILED DESCRIPTION

[0032] It is a feature of the present disclosure that the approach taken by the majority of identified prior art to focus on the creation of Digital Terrain Models (DTMs) to create boundary models using established systems and methods is disregarded and new systems and methods are used in order to create higher accuracy models which are suitable for the functionality described herein, namely for the accurate tracking of vehicles on driving surfaces relative to predetermined boundaries of the driving surface.

[0033] In particular, embodiments described herein describe systems and methods to define very accurate digital boundary models (DBMs) of boundary limits on driving surfaces such as roadways, car parks and racetracks that cover significant geographical areas. The present disclosure can be used to help create fully digital racetracks and road transport systems. The DBMs may be used to determine if a position of a real vehicle, whose dynamic position in relation to a DBM is being continuously and accurately monitored by a tracking system, has exceeded, transgressed or is approaching a real boundary or threshold of the real driving surface that has a priori been determined as an acceptable limit from the point of view of regulation, sporting rules, safety or any other consideration. This is achieved by determining whether a virtual representation of the vehicle has transgressed or is approaching the boundaries represented by the DBM within a virtual representation of the driving surface.

[0034] The DBMs which are created in the present embodiments comprise digital data model representations of the predetermined boundary limits of a driving surface with a representational accuracy of better than 10mm compared to real-world truth. Real world examples of the boundary limits include but are not limited to the predetermined edges (inner, outer, leading, trailing or any combination) of white or coloured lines that mark the edges of a roadway or racetrack or of lines that mark the boundaries between driving lanes or of lines that mark the starting grid positions on a racetrack or of lines that represent stopping limits at road junctions or of lines that delimit parking bays in a car park or any other marking on or feature of a driving surface (a surface which is designed for a vehicle to travel on).

[0035] Further, the created DBMs may also in some embodiments include representations of unmarked boundary limits on the surface which are implied by the presence of marked boundary limits on the surface, such as the gaps between the elements of dashed lines representing the boundary between driving lanes, a gap in markings where there is a fork in the driving surface, or a pit-lane exit on a racetrack.

[0036] As discussed above with reference to References [1] to [3], a vehicle being tracked for the purposes of autonomous, semi-autonomous or automated driving systems (ADSs) and / or for the purposes of determination of whether a vehicle has crossed a predetermined boundary in motorsports, will require a lateral tracking accuracy of the vehicle to be better than 10cm in relation to the predetermined boundaries to establish a functional system. Furthermore, the accuracy of the established position of the relevant predetermined boundary limits will need to be an order of magnitude greater than this (i.e. 10mm) in order to not compromise the vehicle tracking accuracy. However, the establishment of levels of model accuracies in comparison to real-world truth can be susceptible to ‘circular logic’ or ‘self-fulfilment’ or the accumulation of errors across multiple measurements and hence, in order to avoid these pitfalls the individual boundary model measurements will typically need to be a further order of magnitude more accurate again - namely approximately to the order of magnitude of 1-2mm with respect to real-world truth. In effect, in order to establish an accurate tracking system capable of determining whether a vehicle has exceeded a particular boundary in accordance with existing requirements, it is necessary to establish the real world position of every point on a large real-world boundary (with respect to a designated origin or reference point) to a precision of the order of magnitude of 10mm or better.

[0037] It is a feature of the embodiments described herein that in order to establish the required precision when determining the real-world position of a boundary to create a corresponding DBM, a position sensing system is utilised capable of measuring to the required level of precision. This position sensing system comprises a sensor or sensor device and a boundary marker which are used together to record measurements of the real world positions of a plurality of points of the predetermined boundary with respect to an established reference point, with these recorded positions being provided to an appropriately configured processing system to establish the corresponding DBM. The boundary marker is typically reflective of laser light shone on it by the sensor or sensor device.

[0038] It has been appreciated that in certain situations, ‘Total Station’ surveying equipment can give relative positional accuracies between local measurement points as good as 1-2mm (Ref [4]: Leica TS16 Total Station Data Sheet). Hence the methods in some embodiments of the present disclosure make use of a laser measuring device, such as a Leica TS16 Robotic Total Station, and a separate tripod-mounted prism to reflect light back to the measuring device from a measurement point. It is to be appreciated however that the methods and systems described herein are not limited to the use of any particular type of sensor device (such as the Total Station surveying equipment), and that any sensor or sensor device may be utilised which is able to achieve the required precisions described herein.

[0039] Following the establishment and transmittal of the recorded positions to a processing system, the processing system may be configured to create the corresponding DBM. The output DBM of the embodiments described herein is a digital data set comprising one or more accurate polylines which are created by measuring, constructing, and recording a plurality of splines directly through respective pairs of sequential points, identified in three dimensions against a defined datum, using the position sensing system (e.g. laser equipment with reflector)

[0040] Specific embodiments are now described with reference to the appended figures.

[0041] Turning to Figure 1, there is shown an overview of the complete digital boundary model (DBM) creation apparatus 100 as deployed for the creation of a DBM 103 representative of predefined boundaries of a physical driving surface in accordance with embodiments described herein. The apparatus 100 comprises a position sensing system 102 which is deployed on or around a driving surface 104 for which a DBM 103 is to be created (representing pre-established visible boundaries 105 on the driving surface 104). The position sensing system 102 comprises a sensor device (or sensor unit) 150 and a reflector device 150a which together are configured to establish the position of a plurality of points on a pre-established typically marked boundary 105 of the driving surface 104 relative to an established origin or reference point and to record the relative position of each of the plurality of points as position data. More details regarding the position sensing system 102 are provided with reference to Figure 2B below.

[0042] Additionally, the apparatus 100 comprises a processing system 108. The processing system is configured to create the DBM 103 corresponding to the pre-established boundaries 105 of the driving surface 104. The processing system 108 is configured to create the associated DBM 103 based on the position data determined and recorded by the position sensing system 102. Accordingly, the sensing system 102 may be configured to transmit determined position data to the processing system 108. This may be transmitted via a wireless communications network 106. Alternatively, where appropriate, the position sensing system 102 and the processing system 108 may be directly coupled via wired means and transmission of the determined position data may be enabled via the wired means. It is also to be appreciated that whilst the processing system 108 is shown separately from the position sensing system 102 in some instances, the position sensing system 102 may itself be provided with a processing system 108 configured to create the associated DBM based on the determined position data. Such a processing system 108 may be included as part of the position sensing system 102. In such instances, the sensor device may be configured to transmit data via the comms network 106 to other systems that use the DBM 103.

[0043] In some embodiments, the position sensing system 102 may be configured to provide the position data regarding a plurality of points on a pre-established boundary 105 of the driving surface 104 directly to a human operator via a visual display. In such cases, the operator may then directly input the data into the processing system 108 to be used in the creation of the DBM 103.

[0044] The processing system 108 is configured to utilise the received position data regarding the plurality of points on the pre-established boundary 105 of the driving surface 104 to create an output DBM. The output DBM 103 is a digital data set comprising one or more accurate polylines which are created by measuring, constructing and recording a spline directly through sequential points on the pre-established boundary 105 of the driving surface 104, identified in two or three dimensions against a defined datum or reference point, using the position sensing system 102. The polyline is created from combining a plurality of the splines together. The created polyline thereby establishes a digital model of the physical boundary for all corresponding points of the boundary (not just those points for which position data has been provided).

[0045] The output DBM 103 may then be configured to be used by comparing the established polylines to a digitally reconstructed tracked position of a real vehicle on the driving surface 104 relative to the DBM, in order to determine whether the vehicle has exceeded, transgressed or is approaching a pre-established boundary 105 of the driving surface 104 in the real world. This may be achieved by establishing a relative position of the digitally reconstructed tracked position of a real vehicle to the reference point of the DBM and performing a comparison to the relative position of the DBM. In some embodiments, this determination may also be made by the processing system 108. In such embodiments, the processing system 108 may also be configured to receive information regarding the reconstructed tracked position of a real vehicle on the driving surface 104 and perform a comparison to the DBM digital data set to determine whether such a transgression has occurred. In other embodiments, the determination is performed by a separate system, and following creation of the DBM digital data set, the processing system 108 may be configured to transmit the digital data set to the appropriate system for subsequent use in this manner. More details regarding the processing system 108 are provided with reference to Figure 2A below.

[0046] In some embodiments, the pre-established boundaries 105 represent visible features on a driving surface (e.g., the edge of a rack track marked with a line, the hard shoulder on a motorway marked with a line etc). In other embodiments, the pre-established boundaries 105 may represent boundaries which are entirely or partially not visible (e.g., dashed lane markers on a multi-lane road, an unmarked boundary in a pit lane on a racetrack).

[0047] In some embodiments, the output DBM digital data set may also be used to visually display a virtual representation of the pre-established boundaries 105 of the driving surface 104 on a virtual representation of the driving surface 104. This may be enacted via employment of a suitably configured graphics processor which is configured to receive the output DBM digital data set and display this on a virtual model of the relevant driving surface 104 and where appropriate, an area surrounding the relevant driving surface 104. This may be achieved by locating the corresponding position of the reference point of the DBM within the virtual representation of the driving surface 104 and overlaying the polyline(s) of the DBM in accordance with this determination.

[0048] It is also to be appreciated that in some instances, a single driving surface 104 may comprise multiple pre-established boundaries 105 (e.g. a racetrack may comprise an inner and outer track edge boundary, a pit lane boundary and multiple starting grid marker boundaries). In such cases, a separate DBM 103 may be created for each of the pre-established boundaries. Alternatively, a single output DBM data set may incorporate separate polylines for each of the relevant pre-established boundaries and used in accordance with the embodiments described above. Each different DBM or polyline would have associated metadata to characterise the various track boundary types that were represented, for example, track limit DBM, start grid DBM, etc.

[0049] Referring now to Figure 2A, there is shown in greater detail a schematic block diagram of the processing system 108 of Figure 1. The processing system 108 firstly comprises a receiver 120 configured to receive incoming data in accordance with embodiments described herein. In particular, the receiver 120 is configured to at least receive position data relating to a plurality of points on a pre-established boundary 105 of the driving surface 104 relative to an established origin or reference point which has been determined by the position sensing system 102. In some embodiments, the receiver 120 is configured to receive this position data directly from the sensor device of the position sensing system 102 either through a wired connection or via a wireless communications network 106. Such wireless communication may be enabled via radio frequency communication. Alternatively, the receiver 120 may receive this data using any other suitable form of communication, which enables the data to be received in the required format to enable functionality described herein. In some embodiments, the receiver 120 is configured to receive the relevant position data through manual data entry from a human operator.

[0050] In some embodiments, the position data relating to a plurality of points on a pre-established boundary 105 of the driving surface 104 for the creation of a single DBM 103 may be received incrementally (i.e. a series of data points may be received separately). In alternate or additional embodiments, each of the data points relating to a single DBM may be received simultaneously following all data points having been previously measured. More details regarding the collection of data and its provision to the processing system 108 will be provided with reference to Figure 2B below.

[0051] The processing system 108 further comprises a data store 122 and a processor 124, which is communicably coupled to the data store 122 and to the receiver 120 or to a manual data entry device (not shown) in accordance with embodiments described above. The processor 124 may be configured to receive data which is received by the receiver 120 or a manual entry device and store the received data in the data store 122. In particular, this received data may at least comprise the position data relating to a plurality of points on a pre-established boundary 105 of the driving surface 104 relative to an established origin or reference point which has been determined by the position sensing system 102. In some other embodiments, the processor may also be configured to receive additional data such as the position of tracked vehicles on the relevant driving surface 104 which has been received via the receiver 120 which may be stored in the data store 122 in a similar manner. In some embodiments, when data is received by the receiver 120, the data may be directly stored in the data store 122 after being received either prior to, or simultaneously with the data being provided to the processor 124. The processor 124 may also be configured to retrieve any required data previously stored in the data store 122 via a communicable coupling between the two.

[0052] The processor 124 is configured to create DBMs 103 in accordance with embodiments described herein utilising the received position data determined by the position sensing system 102 (either directly from the position sensing system 102 or otherwise) and store the same in the data store 122. In particular, the processor 124 is configured to create splines (in accordance with commonly used techniques) between two points represented by the received position data and which are designated as being sequential along the pre-established boundary 105. This sequential designation may be indicated within a data structure of the data which is received or inputted by the processor 124 (e.g. by each data point being assigned a number representing its sequential position). Alternatively, the processor 124 may be configured to perform a determination of the sequence of each of the points based upon the indicated position of the points (for example, for a particular data point, determining the two points surrounding this point which are the shortest distance away and designating that these represent a sequence of points and repeating this process for all received data points). Whilst one example of this is provided for illustration, it is to be appreciated that any suitable technique may be utilised to enable this functionality.

[0053] Following the creation of splines between consecutive data points, the processor 124 is configured to create a polyline by connection of adjacent splines (in accordance with commonly used techniques). The created polyline functions as the DBM 103, which is a virtual representation of the physical pre-established boundary 105 of the driving surface 104, and which may be used to determine whether a vehicle on the driving surface 104 has transgressed the boundary 105 by comparison of the DBM with a virtual reconstruction of a tracked position of the vehicle. Also in some applications, the created polyline may be used to maintain a vehicle within boundaries for example in a lane marked out on a road surface (such as a motorway). In this example, the vehicle can be kept equidistant from the lane lines on either side of the vehicle as it is moving by knowing its position relative to the boundary lines. In some embodiments, the processor 124 is configured to perform this determination. In such embodiments, the processing system 108 may be configured to receive tracking data of the relevant vehicle via the receiver 120 (which may or may not be stored in the data store 122), and perform a comparison between the tracking data (establishing the position of the vehicle) and the established DBM 103. In other embodiments, the determination of whether a vehicle on the driving surface 104 has transgressed the boundary 105 may be made by a separate system (not shown). In such cases, the processor 124 may be configured to, upon creation of the DBM 103, transmit the digital data set to the separate system via a transmitter 126 of the processing system 108 to which the processor 124 is communicably coupled. The transmitter 126 may be configured to transmit any required information in accordance with the above embodiments. In particular, this may include the DBM digital data set, the previously received and / or stored position data and any received tracking data of any relevant vehicle(s).

[0054] In some embodiments, the processor 124 may also be configured to generate a visual representation of the pre-established boundaries 105 of the driving surface 104 represented by the output DBM digital data set. This may be achieved by virtually overlaying the polyline of the DBM onto a virtual representation of the driving surface 104. The virtual model may be provided to the processing system 108 via the receiver 120 and stored in the data store 122 for retrieval by the processor 124. The overlaying of the output DBM may typically be enacted by locating the established reference or origin point of the DBM within the virtual model of the driving surface 104 and mapping the output DBM digital data set onto the virtual model with reference to the located point. The virtual model with the overlaid DBM may then be transmitted via the transmitter 126 to an appropriately configured display screen (not shown). In some embodiments, the visual representation may be generated by systems external to the processing system 108. In such embodiments, the output DBM digital data set may be provided to the relevant external system via the transmitter 126 in accordance with embodiments described above and then used by the external system to generate the visual representation.

[0055] In some embodiments, the created polyline of the output DBM may be an open polyline(namely not forming a loop) with defined start and end points which are different from one another. This may be the case in embodiments wherein the DBM 103 represents a predetermined boundary along a stretch of a road which does not form a closed circuit (e.g. a motorway). In other embodiments, the created polyline of the output DBM may be a closed polyline with defined start and end points which coincide with one another (namely forming a loop). This may be the case where the predefined boundary is a small feature on a driving surface 104 (e.g. a starting grid marker), or where the driving surface 104 forms a looped circuit. In the case where the DBM 103 is a closed polyline, the processor 124 may advantageously be configured to ensure that the measured start and end points coincide to help ensure accuracy of the created DBM. This will be discussed further below. Further, the processor 124 may otherwise be configured to perform a calibration procedure to verify the accuracy of the positional data. This will again be discussed further below.

[0056] Turning now to Figure 2B, there is shown in greater detail a schematic block diagram of the position sensing system 102 of Figure 1. In particular, in Figure 2B, the position sensing system 102 is provided with a sensor unit 150 and a reflector unit 160, with the combination of these units being configured to establish the position of a plurality of points on a pre-established boundary 105 of the driving surface 104 relative to an established origin or reference point. In this embodiment, one sensor unit 150 is provided to measure the position of a plurality of points on a pre-established boundary 105 of the driving surface 104 with the reflector unit 160 being configured to be movable to the position of each boundary points with a measurement being taken at each boundary point.

[0057] Each sensor unit 150 is provided with a sensor 155 configured to enable determination of a position of the reflector unit 160 relative to an established origin point or point of reference on or proximate to the driving surface 104 around which the position sensing system 102 is disposed. In order to effect this measurement, the sensor unit 150 has an emitter 152 for emitting electro-magnetic (EM) radiation towards the reflector unit 150a. The reflector 160 of the reflector unit 150a, reflects the EM radiation back to the sensor unit 150, where it is detected by the sensor 155. The sensor 155 may be any such sensor which enables the required functionality and accuracy (e.g., an infrared sensor, a laser sensor, an ultrasonic sensor etc) and is matched to the emitted EM radiation or other type of signal. It is to be appreciated that the examples provided are for illustrative purposes only and that any appropriate sensor technology may be used.

[0058] The sensor unit 150 also comprises a processor 160 which controls the operation of the emitter 152 and sensor 155. A data store 170 is also provided for storing measured position data following measurement for subsequent retrieval, and a data emitter 165 for transmitting the measured positional data to the processing unit 108. Furthermore, the sensor unit and the reflector unit each comprise positioning units 158, 158a which respectively act to locate the sensor unit and the reflector unit at the correct locations for conducting measurements. These positioning units 158,158a respectively are directed to the ground and are used to position the sensor unit and the reflector unit accurately and at equal heights or precisely measured differing heights over a respective point. This is achieved for the positioning unit 158 of the sensor unit 150 in a standard manner by sensing EM radiation reflected from a reflective ground marker 180 placed on the ground at the desired location. For the location of the reflector unit a marker 180a may be provided or alternatively the reflector unit is just located over the desired point of the boundary (which may simply be measured from the last measurement point along the boundary).

[0059] The sensor unit 150 is located at the established origin or reference point, and the reflector unit 150a is located at one or more points on the pre-established boundary 105. As mentioned above, the sensor unit 150 emits EM radiation (or indeed any other suitable form of emission) toward the reflector unit 150a and detects the return signal from the reflected emission via the provided detector (sensor 155). Suitable examples of such emissions may include infrared, laser, and ultrasonic emissions. In so doing, the sensor unit 150 is able to establish a position of the reflector unit 150a relative to the position of the sensor unit and therefore correspondingly establish a position of the point on the boundary 105 relative to the origin or reference point. This position may comprise both a distance between the sensor units as well as two orthogonal angles in 3D space. A similar effect may be achieved by positioning a sensor unit 150 comprising an emitter and detector at a point on the boundary, and a reflector unit 150a comprising a reflector at the established origin or reference point - though this is not discussed further herein. Further details regarding the preferred implementation of the reflector unit 150a being positioned at the boundary are discussed below with reference to Figure 3.

[0060] In some envisaged embodiments, the measured position of a particular point on a pre-established boundary 105 of the driving surface 104 comprises a point in 2-dimensional space relative to the origin or reference point (i.e. the measured point provides a point in the x-y plane). This may be of use in situations in which the driving surface is substantially flat with extremely low variations in height across the entirety of the driving surface 104 and the pre-established boundary 105. In other embodiments, the measured position of a particular point on a pre-established boundary 105 of the driving surface 104 comprises a point in 3-dimensional space relative to the origin or reference point (i.e. the measured point provides a point in the x-y-z plane). This may be of particular use where some undulation is expected in the driving surface 104 and its associated boundaries 105.

[0061] In some embodiments, the sensor unit 150 may be provided with a Global Positioning System (GPS) sensor 175 in order to enable the sensor unit 150 to be physically located using GPS coordinates and consequently physically locate the position of the reference point and / or the measured points of the boundary 105. This may assist in generally locating the reference point and / or the measured points of the boundary 105 in a corresponding virtual model of the driving surface 104 and areas proximate to the driving surface 104 and / or geo-locating the driving surface 104. In some embodiments, the GPS co-ordinates of the sensor unit 150 are established using Augmented Global Positioning System techniques such as Real-Time Kinematic positioning (GPS-RTK), Differential GPS, Satellite Based Augmented GPS, etc. In all cases, the purpose of the GPS is to provide the geolocation of the overall DBM with respect to some established global or regional coordinate system. The accuracy of this geolocation is not of significance to the tracking of vehicles with respect to the DBMs. The established GPS coordinates may be stored in the data store 170 and subsequently received and / or transmitted using the data transmitter 165 in a manner analogous to transmission of the positional data described above.

[0062] Figure 3 shows an isometric view of present embodiments illustrating a partial arrangement 200 of the position sensing system 102 of Figures 1 and 2 in a use scenario. In this use scenario, sensor unit 150 and the reflector unit 150a of the position sensing system 102) are implemented to determine the position of the boundary 105 represented by the outside edge 202 of a driving surface 104. In particular, the outside edge of the driving surface 104 in this example is substantially straight.

[0063] In the illustrated scenario of Figure 3, a reference sensor unit 204 (functioning as the sensor unit 150) and a marker unit 206 (functioning as the reflector unit 150a) are shown. The reference sensor unit 204 is configured to be positioned at a designated origin / reference point 208, which is located remotely from the driving surface 104 and its respective boundary 202. The sensor unit 208 is typically positioned at a location (marked by pin 180 driven into the ground which acts as the reflective ground marker 180) proximate the driving surface 104. However, in some embodiments, the location of the reference sensor unit can be at an edge of the driving surface 104. The marker unit 206 is movable and is configured to be placed at a variety of points 210A, 210B, 210C, 210D along the boundary edge 202. It is to be appreciated that whilst four points 210A, 210B, 210C, 210D are illustrated, this is for illustrative purposes only and the total number of points may vary in accordance with the requirements of the boundary being measured. In each position, a temporary marker 108a is placed at the appropriate point and the marker unit 206 is positioned directly above the marked point 210A / B / C / D. The reference sensor unit 204 remains at the reference location 208 but the marker unit 206 is iteratively positioned so as to measure the location of each of the consecutive adjacent points 210A, 210B, 210C, 210D along the boundary 105,202, with respect to the reference location 208. This relative positioning is used to generate relative positional data for each of the boundary points 210A, 210B, 210C, 210D which may be used with knowledge of the absolute position data of one of the reference locations (typically a primary or master reference location), in the creation of a DBM 103. Further discussion relating to the positioning of the marker unit with respect to the boundary points to ensure the required level of accuracy is provided below.

[0064] In the illustrated example, and as has been described above, the reference sensor unit 204 is provided with an emitter 152 and a detector (sensor) 155, and the marker unit 206 is provided with a reflector 160, to allow the determination of a relative positioning between the two. The reference sensor unit 204 is configured to emit radiation (or another suitable emission) toward the position of the marker unit 206 in order to establish the position of the marker unit 206 with respect to the reference unit 204 by detecting (with the provided detector (sensor 155)) the radiation which is reflected from the (reflector 160 of the) marker unit 206. It is also to be appreciated that in some instances, the relative positioning may be determined via alternative methods.

[0065] In accordance with known methods, the detection of the radiation may be used to determine two orthogonal angles in 3D-coordinate space between the emitter and detector at which the radiation has been received from, and the distance away from the reference sensor unit 204. For example, the reference sensor unit 204 may comprise an electronic or robotic theodolite combined with an electronic distance meter (EDM), where the marker unit 206 comprises an appropriately configured reflective target that the reference sensor unit 204 is aimed toward. The operation of the theodolite and the EDM may be performed automatically or manually (in accordance with established techniques) to determine the two orthogonal angles in 3D-coordinate space and distance between the 204 and second 206 sensor units in accordance with standard approaches. If the determination is to be for a two-dimensional model in two-dimensional coordinate space, it is only necessary to determine the azimuth. If the determination is fora three-dimensional model in three-dimensional coordinate space, a second measurement is required of the elevation angle. Both are possible using the above-described theodolite. Such techniques can establish the relative positioning between the reference sensor unit 204 and the marker unit 206 to a precision to an order of magnitude of approximately 1mm, in accordance with requirements described above.

[0066] It is to be appreciated that the above arrangement describes how a relative position between the reference sensor unit 204, and the marker unit 206 may be established. However, there will typically be a separation (typically vertical) between the position of the reference sensor unit 204, and the position of the points on the boundary 210A, 210B, 21OC, 21OD at which the reflector unit 206 is to be positioned. To ensure that the DBM created using the measured position data is created at the required degree of accuracy in accordance with embodiments described above, it is necessary to take this difference in position into account. As such, the difference in position between the relevant emitter (152) / reflector (160) or detector (sensor 155) and the point to be measured must also be determined. To address this, a marker may be placed at each of the boundary points 210A, 210B, 210C, 210D to be measured, as well as the origin / reference point 208. These markers may comprise a long metal pin or survey stake driven vertically into the earth such that a top surface of the metal pin or survey stake, which should be distinctive and visible from above, is flush with the surface. However, where this is not possible, such as on a solid tarmac surface, a mark or marker may be used. In the preferred embodiment, no marker 180a is required, as the marker unit 206 can simply be positioned correctly over the boundary measurement point 210A, 210B, 210C, 210D and the reflector 160 can be at a predetermined fixed height (distance) from the measurement point. Prior to determination of the relative positioning of the reference sensor unit 204 and the marker unit 206 the reference sensor unit and the marker unit 204, 206 may undergo a levelling procedure with respect to the corresponding measurement points at the relevant measurement points 208, 210A, 210B, 210C, 210D, to ensure that the reference sensor unit 204 and the marker unit 206 are horizontally level and placed directly above the respective marker / measurement point. This may be achieved by providing the reference sensor unit 204 and the marker unit 206 with a suitably configured laser or mechanical plummet which acts as the positioning unit 158, 158a of the sensor unit 150 and the reflector unit 150a. The vertical distance of each of the reference sensor unit 204 and marker unit 206 from the ground may be predetermined or may in some embodiments be measured. Any difference in height of the reference sensor unit 204 and the marker unit 206 from the ground may be noted. The corresponding height difference between the boundary point 210A, 210B, 210C, 210D and the reference point may then be determined from the measured elevation angle. The difference in vertical positioning (from the ground) between the reference sensor unit 204 and the marker unit 206 may then automatically be corrected for when establishing the position data. Alternatively, the difference in vertical position from the ground may be provided to the processing system 108 in addition to the raw elevation data determined by the reference sensor unit 204wherein the processing system 108 is configured to adjust the received raw elevation data based upon the provided difference in position to determine the correct elevation angle of the boundary points 210A, 210B, 210C, 210D relative to the reference point 208.

[0067] In some embodiments, the sensor unit 204 may comprise a “Total Station” device (such as a LeicaTS16 Robotic Total Station as referred to in Reference [4]). Such devices comprise an electronic or robotic theodolite combined with an electronic distance meter (EDM) housed in a single housing and placed on a tripod. Such devices also typically comprise a laser plummet (or other suitable device) to enable level positioning of the device directly above the relevant point 208. These devices may also typically comprise a height measuring device for measuring the height of the device on the tripod above the relevant reference point 208. A similar height measuring device may be provided in the marker unit 206.

[0068] It is also appreciated that in some instances, the atmospheric conditions may affect the measurement of the position of the boundary point 210A, 210B, 210C, 210D, at least to the extent that the desired level of accuracy cannot be maintained. As such, in some embodiments, the temperature, humidity, and atmospheric pressure at the location to be measured (and any other relevant atmospheric conditions) may be recorded and documented. This information may then be used to adjust the measured position data accordingly. In some instances, this may be adjusted for at the point of measurement. In particular, when using the laser measuring equipment (for example the Total Station laser measuring equipment referred to above) relevant atmospheric details may be input prior to measurement to calibrate the devices.

[0069] The total number of boundary points 210A, 21 OB, 210C, 210D for which positional data needs to be obtained to generate a DBM 103 to the required level of accuracy is dependent upon both the length of the pre-established boundary 105 as well as the shape of the boundary 105. In particular, in instances where the boundary 105 is substantially straight (in both two and three dimensions), it may be necessary to obtain positional data for fewer boundary points 210A, 210B, 210C, 210D due to the inherent simplicity of the boundary 105 than in instances where the boundary 105 is curved and / or undulating. In order to obtain the required level of accuracy for functionality described herein, where the boundary 105 appears to be straight, it is typically necessary to record a position of a point on the boundary 105 at a maximum of 100cm intervals. Where it is ascertained that the boundary is not substantially straight, it is typically necessary to record a position of a point on the boundary 105 at a maximum of 25.0cm intervals. It is to be appreciated that these are maximum intervals only and that more precise information may be obtained by measuring points on the boundary 105 at finer (smaller) incrementations. It is also to be appreciated that in instances where the positional data obtained is in two dimensions only, the boundary 105 may only need to be straight in the same two dimensions.

[0070] Furthermore, it is to be noted that to ensure accuracy of the positional data, it is necessary to ensure that the measured boundary points 210A, 210B, 210C, 210D are less than a maximum distance away from the reference point 208. Typically, to ensure the required accuracy, the measured boundary points 210A, 210B, 210C, 210D need to be at most 80.00 metres away from the reference point 208 (although this distance may vary depending upon the accuracy requirements of the DBM and the accuracy performance of the sensor). It is envisaged that in some embodiments, a DBM will be created for a driving surface 104 for which it is not possible to position the reference point 208 in such a way that the required boundary points 210A, 210B, 210C, 210D are all less than the maximum distance from the reference point 208 (e.g., 80m).

[0071] In such instances, a secondary reference point 220 may be established for which additional boundary points may be measured with respect to. The secondary reference point 220 may be established in a similar manner as described above for the primary reference point (i.e., a reference marker 225 may be placed at the secondary reference point, comprising a long metal pin or survey stake driven vertically into the earth with a top surface of the metal pin or survey stake being flush with the surface. Thereafter, the marker unit 208 is placed at the secondary reference point and its position determined using the sensor unit 206. This position is then used as the secondary reference point 220 and the sensor unit is then moved to the secondary reference point). In the example provided above, the range of the sensor unit 206 for the desired accuracy is 80.00 metres and so the secondary reference point 220 is selected to be within 80.00 metres of the primary reference point 208. The position of the additional boundary points may then be established with respect to the secondary reference point 220 in a manner analogous to that described above with reference to the primary reference point 208 with use of the sensor unit 204 and the marker unit 206.Once the position of the secondary reference point has been determined, the sensor unit 204 and the marker unit 206 are reused and simply relocated from their previous measurement positions. The positional data relating the position of the secondary reference point 220 to the primary reference point 208 and all of the additional boundary point measurements with respect to the secondary reference point 220 are then provided to the processing system 108 in accordance with embodiments described above. This process is then repeated for a third reference point ((not shown) the position of which is determined from the secondary reference point 220), when the limit of measurement of the sensor unit 204 at the second reference point 220 is reached and further sections of the boundary 105 need to be mapped and measured. This process is described below.

[0072] In most circumstances, the boundary to be measured is sufficiently large that the boundary points to be measured are greater than the maximum distance away from both the primary 208 and secondary 220 reference points. In such cases, tertiary, quarternary, quinary and further reference points (not shown) may be established in a manner similar to that described for the secondary reference point 220 above and used to determine relative positions of boundary points with respect to the tertiary, quarternary and further reference point(s). In such instances, the position of the tertiary reference point(s) is measured relative to the secondary reference point 220, the position of the quarternary reference point is measured with reference to the tertiary reference point and so on. In this manner, a chain of relative positions between reference points may be established such that the position of each tertiary, quarternary and further reference points may be determined relative to the preceding adjacent reference point. This approach may be taken for any required number of further reference points such as to enable the determination of any additional boundary points whilst still ensuring that the maximum distance between the boundary points 210A, 21 OB, 210C, 210D and a reference point 208, is less than a predetermined maximum value (80.00 metres in this example) to maintain a specified accuracy level.

[0073] In some embodiments, it is possible to use a single primary reference point 208 (in particular in instances where the driving surface 204 is a closed loop). In this case, the single primary reference point 208 has to be within the predetermined limit of all of the boundary points to be measured, which in the described embodiment is within 80.00 metres. This may be the case, for example, for a go-kart track.

[0074] Figure 4 illustrates an example of a use scenario of embodiments described above. In particular, Figure 4 illustrates an example of a deployment positions for sensor units 204 and marker units 206 at a variety of points around an extended race circuit 230. The sensor unit 204 and the marker unit 206 are deployed at the shown locations to measure the outer edge of a boundary line 105 of the race circuit 230. The outer edge of the boundary line 105 is shown from above and comprises a variety of straight sections and curved sections, wherein the curved sections have varying degrees of curvature. For ease of illustration, the driving surface 104 of the race circuit is not shown.

[0075] The position (locations) of a plurality of boundary points 210A, 210B, 210C, 210D and additional boundary points (represented by black circles) is measured along the boundary line with respect to one of a plurality (nine shown in Figure 4) of reference points (represented by crosses) which is located proximate to the driving surface of the race circuit 230. In particular, each of the boundary points is measured with respect to its closest and prior sequenced reference point, where the reference points 208, 220 have been positioned in order to ensure that no boundary point is greater than a predefined maximum distance away from a reference point (where the maximum distance is based upon the required accuracy of the DBM to be created). This may be achieved in accordance with embodiments described above. One reference point is designated as the primary reference point 208. As each reference point location is measured from a previous reference point location to the required accuracy, the entire circuit is measured to the required accuracy and provided to the processing system to create the DBM 103. A primary / master reference location may have its absolute geographic location determined and all measured points can be determined as relative to that primary / master reference location, the DBM can be created.

[0076] Referring now to Figure 5, there is shown a method of operation 300 of the above DBM creation apparatus 100. In particular, the method 300 is for generating a DBM 103 representing a pre-established boundary of a physical driving surface.

[0077] The method 300 proceeds by the processing system 108 receiving, at Step 302, positional data for each of a plurality of boundary points on the pre-established boundary 105 of the driving surface 104. This may be received via the receiver 120 of the processing system 108. The position data may be received directly from the position sensing system 102 in accordance with embodiments described above. Alternatively, the receiver 120 may receive this data from the position sensing system 102 using any other suitable form of communication, which enables the data to be received in the required format to enable functionality described herein. In some embodiments, the receiver 120 is configured to receive the relevant position data through manual data entry from a human operator. The position data indicates positions of the boundary points relative to one or more reference points either on or proximate to the driving surface 104.

[0078] Following receipt of the position data, the method 300 proceeds by generating, using the processing system 108 at Step 304, a virtual linear spline between pairs of sequential (adjacent) boundary points along the pre-established boundary 105 based upon the received position data of the two sequential points. The spline creates a continuity of the boundary between the two sequential discrete measured points which approximates the actual boundary 105. This sequential designation may be indicated within a data structure of the data which is received or inputted by the processor 124 of the processing system 108 (e.g. by each data point being assigned a number representing its sequential position along the boundary 105). Alternatively or additionally, the processor 124 may be configured to perform a determination of the sequence of each of the points based upon the indicated position of the points (for example, fora particular data point, determining the two points surrounding this point which are the shortest distance away and designating that these represent a sequence of points and repeating this process for all received data points). Whilst one example of this is provided for illustration, it is to be appreciated that any suitable technique may be utilised to enable this functionality. The result of Step 304 is a series of splines between sequential points such that each of the boundary points is connected to one another through the series of splines.

[0079] Once the splines have been created in Step 304, the method 300 proceeds by generating, at Step 306 using the processing system 108, a polyline from the generated splines, namely by connecting them together. This is performed in accordance with embodiments described above. The created polyline functions as the DBM 103, which is a virtual representation of the physical pre-established boundary 105 of the driving surface 104. The created polyline thereby establishes a digital model of the physical boundary for all corresponding points of the boundary (not just those for which position data has been provided).

[0080] Once the polyline has been generated, the DBM may then be exported, at Step 308 via the transmitter 126, to an external system for use in accordance with embodiments described above. This may comprise providing a boundary data set for use with tracked physical vehicle data on the corresponding driving surface 104 to determine if the vehicle is approaching or has crossed the boundary 105. This may also comprise the DBM being used to visually represent the corresponding boundary on a virtual model of the driving surface 104. The method 300 then ends, at Step 310.

[0081] Referring now to Figure 6A, there is shown a method of operation 400 of the sensor system. In particular, the method 400 is for generating the position data to be supplied to the processing system 108 in accordance with Step 302 of the method 300.

[0082] The method 400 of Figure 6A begins at Step 402, by marking a primary reference point 208 either on or proximate to the driving surface 104. The boundary points 210A, 210B, 210C, 210D are measured relative to this reference point 208. Marking the primary reference point may comprise placing a long metal pin or survey stake at the reference point, driven vertically into the earth / ground such that a top surface of the metal pin or survey stake, which should be distinctive and visible from above, is flush with the surface (of the earth / ground). Alternatively, if this is not suitable due to the composition of the surface at the reference point, a position may be marked with an indelible ink marker.

[0083] The method 400 continues by positioning, at Step 404, a sensor unit 150 at the primary reference point 208. This sensor unit may be of the type described with reference to the embodiments described above. In some embodiments, when the reference point 208 is established, the geo location of the reference point is determined using GPS. In some embodiments, the GPS co-ordinates of the sensor unit is established using Global Positioning System Real-Time Kinematic positioning (GPS-RTK) techniques. Whilst not necessary for establishing the DBM, the GPS coordinates can be helpful in geo locating the driving circuit which is formed of the driving surface 104.

[0084] The method 400 proceeds by establishing, at Step 406, the position of the sensor unit 150 with respect to the primary reference point 208. This may be achieved by undergoing a levelling procedure with respect to the primary reference point and determining the height of the sensor unit 150 with respect to the primary reference point 208 in accordance with embodiments described above. This relative position may be recorded and provided as part of the position data supplied to the processing system 108 for use when creating the DBM. If geo location for the primary reference point is required, then the GPS coordinates of the primary reference point may be recorded (as described above) and provided to the processing system. In some embodiments, the measurement is stored on a local data store 170 of the sensor unit 150.

[0085] A boundary point 210A to be measured on the pre-established boundary 105 of the driving surface 104, is then selected, at Step 408. This boundary point 210A is one of a plurality of points on the pre-established boundary 105 whose position will be measured relative to the primary reference point 208. Whilst it is possible in some cases to mark the boundary point 210A with a marker at the boundary point 210A (for example with an indelible ink marker) and place the reflector unit vertically above the marked boundary point, typically, no marker is required.

[0086] The method 400 continues by positioning, at Step 410, a marker unit at the boundary point 210A. Where a marker has been provided this is used. However, where no marker is used, the reflector unit 150a is placed vertically above the selected location with an approximate spacing from the previously measured boundary point. The reflector unit 150a may be of any of the types described with reference to the embodiments described above.

[0087] The method 400 then proceeds by establishing, at Step 412, the position of the reflector unit 150a with respect to the boundary point 210A. This may be achieved by undergoing a levelling procedure with respect to the boundary point and determining the height of the reflector unit 150a with respect to the boundary point 210B in accordance with embodiments described above. Alternatively, the height may be predetermined, and the levelling procedure requires setting up the reflector unit at the correct height. When measured, this relative position may be recorded and provided as part of the position data supplied to the processing system 108 for use when creating the DBM 103. In some embodiments, the measurement is stored on a local data store 17of the marker unit 150.

[0088] The method 400 then proceeds by establishing, at Step 414, the position of the reflector unit 150a relative to the sensor unit 150. This may be achieved in accordance with any of the embodiments described above (e.g. through use of detection of emissions from the sensor unit 150 to determine the distance between the sensor unit 150 and the reflector unit 150aand the two orthogonal angles in 3D-coordinate space between), in order to create position data establishing the relative position of the reflector unit 150a to the sensor unit 150. In some embodiments, the measurement is stored on a local data store 170 of sensor unit 150.

[0089] Once the relative position has been established, the method 400 proceeds by providing, at Step 416, the obtained position data to the processing unit 108. The position data includes data indicating the relative positions of the sensor unit 150 and the reflector unit 150a, and in some embodiments, the relative height positions of the sensor unit 150 and the reflector unit 150a to their respective ground locations (the boundary point 210A and the reference point 208). The obtained position data is transmitted to the processing unit 108 via the appropriately configured data transmitter 165 provided as part of the sensor unit 150. It is to be appreciated that in some embodiments, the transmission of the position data to the processing unit 108 may be provided once the relative position of all required boundary points 210A, 21 OB, 210C, 21OD) to the reference point 208 have been measured (i.e. all required position data has been obtained). In such embodiments, Step 416 may be configured to occur once all the required position data has been obtained. It is also to be appreciated that in some embodiments, the position data which is obtained may be directly input into the processing unit 108 by an operator. In such embodiments, such direct input may replace Step 416.

[0090] Once the position data has been transmitted (or otherwise), the method 400 proceeds by selecting, at Step 418 an additional boundary point 210B, 210C, 210D to be measured on the pre-established boundary 105 of the driving surface 104. This additional boundary point is one of a plurality of points on the pre-established boundary 105 whose position will be measured relative to the primary reference point 208, where the additional boundary point 210B, 210C, 210D is at a different position to previously measured boundary point 210A. The additional boundary point 210B, 210C, 210D will also be configured to be within a pre-established maximum distance of the previously measured boundary point 210A, in accordance with embodiments described above, to ensure that the required accuracy of the position data can be achieved. This distance may vary in dependence upon whether the boundary is straight or curved and / or undulating.

[0091] Following this, the method 400 continues by repositioning, at Step 420, the reflector unit 150a at the additional boundary point 210B. As mentioned previously this can be carried out with or without the use of a marker.

[0092] If the height of the reflector unit 150a is not predetermined, then the method 400 proceeds by establishing, at Step 422, the position of the additional sensor unit 150 with respect to the additional boundary point 210B. This may be achieved by undergoing a levelling procedure with respect to the additional boundary point and determining the height of the reflector unit 150a with respect to the additional boundary point 210B, in accordance with embodiments described above. This relative position may be recorded and provided as part of the position data supplied to the processing system 108 for use when creating the DBM 103. In some embodiments, the measurement is stored on the local data store 170 of the sensor unit 150.

[0093] The method 400 then establishes (measures), at Step 424, the position of the reflector unit 150a relative to the sensor unit 150. This may be achieved in accordance with any of the embodiments described above (e.g. through use of detection at the sensor unit 150 of light reflected from the reflector unit 150ato determine the distance between the reflector unit 150a and the sensor unit 150 and the orthogonal angles in 3D-coordinate space), in order to create position data establishing the relative position of the reflector unit 150a to the sensor unit 150. In some embodiments, the measurement is stored on the local data store 170 of the sensor unit. The relevant measured position data obtained in Steps 422 and 424 is then provided to the processing unit 108 in a manner analogous to Step 416 (or alternatively the position data may be stored for subsequent transmission).

[0094] The method 400 then determines, at Step 426, whether there are any further boundary points 210C, 210D along the pre-established boundary 105 of the driving surface 104 which are to be measured. If there are not, then the method 400 proceeds to end at Step 428. In embodiments in which the position data is not incrementally provided to the processing unit 108 as the position data is obtained, then the position data obtained may be provided to the processing unit 108 after the determination that no further boundary points are to be measured, and prior to the end (at Step 428) of the method 400.

[0095] If it is determined, at Step 426, that there are further boundary points 210C, 210D along the pre-established boundary 105 of the driving surface 104 which are to be measured, the method 400 proceeds to determine, at Step 430, whether the next boundary point 210C, 210D to be measured is greater than a maximum distance from the reference point. Such a maximum distance may be established to ensure that the DBM 103 may be created with the required accuracy in accordance with embodiments described above. If it is determined that the next boundary point 210C, 210D to be measured is less than the maximum distance away from the reference point, then the method returns to Step 418, where the position of the additional boundary point 210C, 210D is selected relative to the primary reference point 208. Then steps 420 to 430 are then repeated forthat selected next boundary point. However, if it is determined at Step 430 that the next boundary point to be measured is greater than the maximum distance from the reference point 208, then it is necessary to determine an further reference point (a secondary reference point 220 initially) in accordance with embodiments described above. In such cases, the method 400 proceeds to Step 452 of method 450, which is described in greater detail with reference to Figure 6B below.

[0096] Referring now to Figure 6B, there is shown a further method of operation 450 of the sensor system. In particular, the method 450 sets out the steps to be followed upon the determination in Step 430 of method 400 that an additional boundary point 210B, 210C, 210D is to be measured which is greater than a predetermined maximum distance away from the reference point.

[0097] The method 450 begins at Step 452, by selecting an additional reference point (for example the secondary reference point 220) either on or proximate to the driving surface 104. Additional boundary points are to be measured relative to this additional reference point 220. The additional reference point 220 is selected so as to be within the measurement range of the sensor unit 150 (which in the above- described example is within 80 metres). Also, the selected additional reference point is chosen so as to enable the determination of further points (additional boundary points) along the driving surface (which were outside the range of the sensor unit 150 positioned at the first reference point 208). The selection can be carried out by using the reflector unit 150a to establish the correct location and distance from sensor unit 206 positioned at the previous reference location (for example the primary reference location 208). The position of this additional reference point, if required, is then marked as has been previously described in relation the primary reference point 208 above. When applying the method 450 for further additional reference points, such as tertiary or quarternary reference points, the additional reference point should be positioned in such a way that it is within the maximum sensing distance (for a required accuracy) from the preceding reference point which has previously been established in accordance with methods described herein.

[0098] Following this, the method 450 continues by removing the reflector unit from the additional reference point and repositioning, at Step 454, the sensor unit at the additional reference point 220. The sensor unit 150 and the reflector unit are then used to measure the positions of the additional boundary points in accordance with methods previously described herein. More specifically, the method 450 proceeds by establishing, at Step 456, the position of the sensor unit 150 with respect to the additional reference point. This may be predetermined as has been mentioned previously or may be achieved by undergoing a levelling procedure with respect to the additional reference point and determining the height of the sensor unit 150 with respect to the additional reference point 220 in accordance with embodiments described above. This relative position may be recorded and is then provided at Step 458, as part of the position data, to the processing system 108 for use when creating the DBM 103. In some embodiments, the measurement is stored on the local data store 170 of the sensor unit 150.

[0099] In this way, the relative positions of the reference points 208, 220 may be established when creating the DBM and the positions of further boundary points 210C, 210D may be established both with respect to the additional reference points and the initial reference point 208 as a result. This may be of importance when creating a DBM 103 where all points on the boundary are to be established with respect to a single (primary) reference point 208.

[0100] Following this, the method then returns to Step 418 of method 400 where an additional boundary point is marked on the boundary 105 of the driving surface 104 which is to be measured. Then Steps 420 to 430 of the method 400 are repeated forthat selected next boundary point. When the additional boundary points are measured in this way, their position is measured relative to the newly positioned additional reference point and the position data generated reflects this. When provided to the processing unit 108, the processing unit 108 may be configured to combine the position data indicating the relative position of the boundary point to the additional reference point 220 and the position data indicating the relative position of the (primary) reference point 208 to the additional reference point 220, resulting in position data relating the boundary point to the (primary) reference point 208.

[0101] It is to be appreciated that modifications to the above-described methods may be implemented in accordance with other optional embodiments described herein.

[0102] Below is provided an example of an implementation of the above-described embodiments. It is to be appreciated that this example is provided by way of illustration only.

[0103] According to an embodiment of the present disclosure, for the purposes of illustrative explanatory example, there is provided a system and method for creating a DBM for a racetrack, the DBM representing the outer edge of a line provided on the physical racetrack which indicates an area that vehicles on the racetrack are not permitted to cross over. For the purposes of illustrative example, Figure 7 shows the start / finish straight of a motor racing circuit on which the white lines define the left- and right-hand track limits and the starting grid positions for the cars. The left- and right-hand track limit lines both continue completely around the racing circuit and their length can be many miles, with a small number of breaks, for example the pit lane entry and exit.

[0104] The measurement method of the present illustrative embodiment is defined by applying it to create a 10mm accuracy 3D-data polyline representing the outer edge of the left-hand line. It may be necessary, depending on the quality and accuracy of the white lines, to have them repainted. The method for this illustrative embodiment involves the following steps: 1) Record and document temperature, humidity, and atmospheric pressure at the location to be measured. Enter this data into the laser measuring equipment (for example the laser measuring equipment referred to above) to allow proper calibration. For the purposes of this illustrative example, it will be assumed that the Leica TS16 Robotic Total Station previously referenced is being used. 2) Establish a master control station (MCS), such as reference point 208, by picking a point on the terrain surface which is not between the track limit lines. This can therefore be at a point separate to the driving surface 104. The MCS 208 is marked with an immovable marker (reference marker 225) such as a long metal pin or survey stake driven vertically into the ground such that a top surface of the metal pin or survey stake, which should be distinctive and visible from above, is flush with the ground surface. The MCS serves as the reference or origin point against which the position of the physical boundary and the corresponding DBM is measured. 3) Locate the laser measuring device tripod vertically above the MCS point 208, for example using the equipment’s laser plummet, go through the levelling procedure. The height of the equipment above the MCS 208 can be measured automatically using the built-in functionality of the equipment and used in subsequent steps. 4) If desired the laser measuring equipment can be used in combination with Global Positioning System Real-Time Kinematic positioning (GPS-RTK) to establish the GPS co-ordinates of the MCS. This can be established using the Leica Smart station for example. This is not strictly necessary for the present disclosure as the DBM for the racing circuit will be created in relation to the MCS, but it may be useful for geo-locating the racing circuit. The MCS point on the surface in 3-dimensional space becomes the reference point datum for subsequent laser-based measurements. 5) Next, place a target reflecting prism mounted on a target pole and tripod above the first point on the track limit white line (the boundary edge 202) to be measured relative to the MCS 208, referred to as Point 1. Again, standard techniques are used to precisely position the prism above the point on the ground on the outer edge of the white line. The point chosen must not be more than 80 metres from the MCS 208 to ensure the 1mm accuracy of the relative position measurement, and there must be line of sight between the laser measuring equipment above the MCS to the prism. Point 1 (P1) 210A can if required be marked on the surface, for example with an indelible ink marker. If so marked, the sequence number of the boundary point can also be provided. This may help if the boundary point is to be referenced again. However, more typically no marking is strictly required for the boundary points as has been explained previously. 6) Use the laser measuring equipment to record the two angles in 3D-coordinate space (such as azimuth and elevation) and the distance between the MCS 208 and the Point 1 210A. Record this as Point 1 in the laser device memory and use the recorded Point 1 to generate the 3-dimensional point in space of P1, with reference to the MCS, such that Point 1 is recorded with an x, y, z relative co-ordinate. 7) If the white line is observed to be straight, both in the x-y and z planes, such as in Figure 1, then the prism pole is moved along the white line by a maximum of 1.00 metres. Then a Point 2 (P2) 210B is recorded in the same way as P1 above - see Figure 8. 8) If the white line is observed to be curved, such as in Figure 9, then the maximum distance to move along the feature is 25cm. This limit ensures that for typical curved features on driving surfaces the maximum distance between the spline component linking two adjacent measurement points and the actual line being measured along the curved feature is well within the 10mm accuracy target for the whole DBM. 9) If in either case, a second point (P2) 210B along the white line (boundary edge 202) would exceed a distance of 80.00m from the MCS, then proceed to the next step, otherwise keep repeating this step to record the x, y, z relative co-ordinates of the points on the emerging polyline 270. Figure 10 shows an example of a straight spline 260 being determined from two adjacent boundary points 210A, 210B for use as a polyline and Figure 11 show an example of a polyline 270 being generated from a plurality of smaller curved splines 260. 10) Once the distance along the feature approaches the 80-metre limit from the MCS, choose an additional reference point on the surface which will become a Secondary Control Station (SCS) 220, 290. This point must not exceed the 80-metre limit of the embodiment from the MCS 208 and must have a clear line of sight to the MCS. It must not be located between the track limit white lines 105. This point, SCSI, 220 can be marked as above with an immovable marker (reference marker 225) such as a metal pin or immovable sticker or another appropriate marker, given the surface type. 11) Record the SCSI 220 position using the prism as for Point 1 in relation to the MCS 208 in the laser device software. Move the laser measuring device to SCSI 220 and ensure, as above, that the device is precisely positioned above the SCSI marker 225, in a stable level position. Ensure automatically levelling compensation and auto-height measurement is enabled in the laser device software. From that control station (SCSI), continue to plot and incrementally number the points which define the polyline 270 (as described above). Consider also measuring points along other features if required, such as starting grid markers 280 or track islands. These features would each have their own defined DBMs comprised of one or more polylines as shown in Figure 12. 12) When the 80-metre limit is reached again repeat the appropriate steps above to establish SCS2 220B, and so on until Point 1 is about to be reached. An exemplary set of locations of the MCS and SCSs together with the locations of the points which define the polyline 270 are shown in Figure 13. 13) Finally, re-measure the x, y, z co-ordinates of P1 with the laser device at its final SCS location and compare the measurement with that obtained from the MCS 208. If all the steps above have been carried out correctly the final measurement of P1 will coincide with the initial measurement to a most likely (root mean square) accuracy of approximately 10mm fora circuit of 8km in length -which is typical of a high end, regulated motor racing circuit.

[0105] Figure 14 shows an example of a final, closed polyline 270A going around a complete racing circuit and a zoomed in section of the polyline 270 showing the individual splines 260 that make up the polyline 270. Once the measurement process is complete then the results can be exported for use. In the present embodiment of the disclosure, the x, y, z co-ordinates of each point on each line are exported to a text or data file in XYZ file format. In the XYZ format, each line in the file represents a single point with its X, Y, and Z coordinates. The order of points in the file defines the sequence along the line. Text fields at the end of each line can be provided to define the name of the polyline 270A and other metadata, as required. Also, the x, y, z co-ordinates can be exported to a Scalable Vector Graphics file. Also, the full data can be exported to a topological plan view in .DWG and Open USD formats, if required.

[0106] Finally, the same procedure is followed when creating DBMs 103 of relatively small features such as the starting grid box on a motor racing circuit. In these cases, all measurements can be done from the same SCS, however a closed polyline 270A must be produced in the same way, no matter how thin or fine the features of the surface marking. When creating DBMs of long roads such as motorways, freeways or highways the total length should be modelled in terms of sections of no more than 8Km, and open polylines created for the longest features such as a continuous, solid line marking the road centre, the width of the line being recorded at regular intervals using a standard ruler.

[0107] Having described several exemplary embodiments of the present embodiments and the implementation of different functions of the device in detail, it is to be appreciated that the skilled addressee will readily be able to adapt the basic configuration of the system to carry out described functionality without requiring detailed explanation of how this would be achieved. Therefore, in the present specification, several functions of the system have been described in different places without an explanation of the required detailed implementation as this is not necessary given the abilities of the skilled addressee to implement functionality into the system.

[0108] Furthermore, it will be understood that features, advantages, and functionality of the different embodiments described herein may be combined where context allows.

Claims

1. A method of generating a digital boundary model representing a pre-established boundary of a physical driving surface using a processing system, the method comprising:receiving positional data for each of a plurality of boundary points on the pre-established boundary, where the positional data of each of the plurality of boundary points comprises a relative position of the respective boundary point to a reference point on or proximate to the driving surface;generating a plurality of virtual splines using the received positional data, each virtual spline comprising a plurality of interpolated points positioned between two adjacent boundary points of the plurality of boundary points along the pre-established boundary; andcomposing the digital boundary model from the plurality of virtual splines, wherein the digital boundary model represents the pre-established boundary and comprises a polyline created by combining the plurality of generated spines and wherein each interpolated point of the polyline represents a boundary limit of the digital boundary model.

2. The method of Claim 1, wherein each boundary point has a respective sequential number indicating the respective position of the boundary point along the pre-established boundary and the positional data of one of the boundary points comprises the sequential number of the boundary point.

3. The method of Claim 1, wherein generating the plurality of virtual splines comprises:using the positional data of each boundary point to determine the relative positions of the boundary points; andassigning a respective sequential number to each boundary point indicating the respective position of the boundary point along the pre-established boundary.

4. The method of Claim 2 or 3, wherein composing the digital boundary model comprises using the sequential numbers of boundary points to combine the plurality of generated splines in a corresponding sequential order.

5. The method of any previous claim, wherein composing the digital boundary model comprises connecting a first one of the plurality of splines with a last one of the plurality of splines to create a closed polyline representing a looped pre-established boundary.

6. The method of any previous claim, wherein the positional data for each of the plurality of boundary points comprises information representative of the boundary point in two dimensions and generating the plurality of virtual splines comprises generating a spline in two-dimensional coordinate space.

7. The method of any of Claims 1 to 5, wherein the positional data for each of the plurality of boundary points comprises information representative of the boundary point in three dimensions andgenerating the plurality of virtual splines comprises generating a spline in three-dimensional coordinate space.

8. The method of any previous claim, wherein the positional data for each of the plurality of boundary points comprises geographical location information representative of the geographical location of the boundary point and the method further comprises providing the geographical location information to a modelling system to geographically locate the pre-established boundary in a virtual model of the physical driving surface.

9. The method of any preceding claim, further comprising measuring positional data of the boundary points along the pre-established boundary; the measuring step comprising:Establishing a reference point outside of or at the driving surface and placing a reference sensor at the reference point;Locating one of the plurality of boundary points as a measurement point on the pre-established boundary and placing a boundary reflector at the measurement point,Using the reference sensor and the boundary reflector to measure two orthogonal angles within a 3D-coordinate system and a distance between the measurement point and the reference point;Recording the two orthogonal angles and the distance between the measurement point and the reference point as the positional data of the measurement point.

10. The method of Claim 9, further comprising:moving the boundary reflector to another one of the plurality of boundary points along the pre-established boundary adjacent to the measurement point to establish a new measurement point.

11. The method of Claim 10, wherein the moving step comprises moving the boundary reflector a first predetermined maximum distance along the pre-established boundary where the pre-established boundary comprises a substantially linear section between the measurement point and the new measurement point.

12. The method of Claim 10, wherein the moving step comprises moving the boundary reflector a second predetermined maximum distance along the pre-established boundary where the pre-established boundary comprises a substantially non-linear section between the measurement point and the new measurement point.

13. The method of Claim 12, wherein the second predetermined maximum distance is less than the first predetermined maximum distance.

14. The method of Claim 13, wherein the first predetermined maximum distance is 1.00 metres15. The method of Claim 13 or 14, wherein the second predetermined maximum distance is 0.25 metres.

16. The method of any of Claims 10 to 15, further comprising repeating the using and recording steps with respect to the new measurement point to determine positional data for the new measurement point within a predetermined range from the reference point.

17. The method of any of Claims 10 to 15, wherein the using step comprises determining the distance between the reference point and the new measurement point is greater than a predetermined reference distance, and the method further comprises: repositioning the reference sensor at a new reference point such that the distance between the new reference point and the new measurement point is less than the predetermined reference distance.

18. The method of Claim 17, wherein the using step comprises determining the distance between the reference point and the measurement point is greater than 80 metres.

19. The method of Claim 17 or 18, further comprising selecting a location of the new reference point to be within 80 metres of the reference point.

20. The method of any of Claims 9 to 19, wherein the receiving step comprises receiving positional data for each of a plurality of boundary points on the edge of a racetrack.

21. The method of any of Claims 9 to 19, wherein the receiving step comprises receiving positional data for each of a plurality of boundary points on the edge of a starting grid marker of a racetrack.

22. A system for generating a digital boundary model representing a pre-established boundary of a physical driving surface, the system comprising: a processing system configured to:receive positional data for each of a plurality of boundary points on the pre-established boundary, where the positional data of each of the plurality of boundary points comprises a relative position of the respective boundary point to a reference point on or proximate to the driving surface;generate a plurality of virtual splines using the received positional data, each virtual spline comprising a plurality of interpolated points positioned between two adjacent boundary points of the plurality of boundary points along the pre-established boundary; andcompose the digital boundary model from the plurality of virtual splines, wherein the digital boundary model represents the pre-established boundary and comprises a polyline created by combining the plurality of generated spines and wherein each interpolated point of the polyline represents a boundary limit of the digital boundary model.

23. The system of Claim 22, further configured to measure positional data of the boundary points along the pre-established boundary; the system further comprising:a reference sensor placed at a reference point outside of or at the driving surface;a boundary reflector placed at a measurement point on the pre-established boundary;wherein the processing system is configured to use the reference sensor and the boundary reflector to measure two orthogonal angles in 3D-coordinate space and a distance between the measurement point and the reference point; andrecord the two orthogonal angles and the distance between the measurement point and the reference point as the positional data of the measurement point.

24. The system of Claim 23, wherein the reference sensor comprises a theodolite and a distance sensor incorporating an infrared laser.

25. The system of Claim 24, wherein the reference sensor is configured to enable the horizontal levelling of the sensor.

26. The system of any of Claims 22 to 25, wherein the reference sensor comprises a wireless transmitter to transmit measurements made at the reference location to the processing system.T +44(0)30 0300 2000A

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