METHOD FOR MEASURING THE DISTANCE OF A VEHICLE FROM A RAMP

Description

[0001] The present invention relates to a method for measuring the distance between a vehicle, more particularly a railway or road transport vehicle, for example a guided road transport vehicle, and a platform.

[0002] Document JP 2011016432 A describes a device for determining the presence of a quay based on calculations made in relation to an expected height.

[0003] Document EP 2 873 582 A1 describes a gap-filler control device and an associated control method, in which the deployment of the gap-filler and / or the opening of the door is decided based on detection information. This information is provided by an image processing unit that acquires images from waves reflected by object contours.

[0004] However, this method does not allow for a reliable measurement of the distance from a rail or road transport vehicle, especially guided vehicles, to a platform.

[0005] Such a measure allows, for example, the output of the gap filler to be precisely adapted to the geometry of the platform.

[0006] One of the aims of the invention is to provide a reliable method for measuring a given distance from a vehicle to a dock.

[0007] To this end, the object of the invention is a measurement method according to claim 1.

[0008] Measuring the vertical distance of the rail vehicle or guided road transport vehicle to a platform allows, in particular, for the height of the vehicle to be adjusted in order to reduce any vertical gap between the platform and an exit of the vehicle.

[0009] The process may also have one or more of the features of claims 2 to 8, considered individually or according to all technically possible combinations.

[0010] Other features and advantages of the invention will become apparent from the detailed description given below, by way of example and not limitation, with reference to the attached figures, including: [ Fig. 1 ] there figure 1 is a schematic view of a vehicle near a platform, [ Fig. 2 ] there figure 2 is an enlarged schematic view of area A of the figure 1 , And [ Fig. 3 ] there figure 3 is a schematic view of a process according to a first embodiment of the invention.

[0011] The invention relates to a method for measuring a given distance between a vehicle 10, in particular a railway vehicle or a road transport vehicle, for example a guided road transport vehicle, and an upper surface 14 of a platform 16. More particularly, the given distance is measured between a marker 12 of said vehicle and said upper surface 14 of the platform 16.

[0012] Platform 16 is, for example, a platform at a station for a rail vehicle or guided road transport vehicle. Alternatively, platform 16 is a sidewalk next to which the vehicle parks.

[0013] We define a vertical or elevation direction Z as the direction perpendicular to a rolling plane of the vehicle, a longitudinal direction X as the usual direction of movement of the vehicle in the classical sense and a transverse direction Y as the direction perpendicular to the longitudinal direction X and the elevation direction Z.

[0014] A dimension defined as "height" is defined as a dimension in the direction of elevation.

[0015] Reference point 12 is, for example, a point in a gap filler designed to reduce the distance between an exit of vehicle 10 and platform 16, in order to facilitate the boarding and / or disembarking of passengers and objects.

[0016] Vehicle 10, for example, is parked at platform 16.

[0017] The measurement method, according to a first embodiment of the invention shown in the figure 3 , comprises the following steps: provision 100 of a detection system 18 mounted on the vehicle 10, projection 110 of a plurality of rays by the detection system, measurement 120, for each ray, of a distance between the detection system and the platform according to said ray detected by the detection system, exclusion 130 of a first part of the measured distances, and calculation 140 of a vertical distance between a reference point on the vehicle and the upper surface of the platform from distances not included in the first part of the measured distances.

[0018] The detection system 18 is capable of projecting a beam 20, for example a laser beam, in the direction of platform 16.

[0019] Alternatively, the 20 ray is a radar technology ray or an ultrasonic ray.

[0020] The detection system 18 is also capable of detecting the ray reflected by an obstacle and of measuring the time interval between the emitted ray and said reflected ray, so as to calculate the distance between the detection system 18 and the obstacle according to the direction of the emitted ray.

[0021] The detection system 18 allows, for example, remote sensing by laser (or "lidar").

[0022] The use of laser remote sensing makes it possible in particular to have a particularly open field of vision of the detection system 18, for example between 0° and 270°, so that a quay edge near which the vehicle is parked is always in the field of vision.

[0023] Advantageously, each beam emitted by the detection system comprises a plurality of echoes; that is, the beam is composed of a plurality of laser pulses. The detection system 18 is capable of distinguishing each of the beam's echoes during beam detection.

[0024] The multiple echoes allow for better operation of the detection system in rain, fog, and / or snow. For example, in rain, the first echo is likely to encounter a raindrop in flight on the beam's path, while the second echo would measure the distance to the next obstacle, such as the platform.

[0025] The detection system 18 is mounted on the vehicle at a height exceeding the maximum dock height. The maximum dock height is the maximum height a dock is likely to have next to the vehicle.

[0026] The maximum platform height corresponds, for example, to the height of a step of an exterior door of the vehicle plus or subtract a margin of between 0 and 500 mm.

[0027] During projection stage 110, the beams emitted by the detection system 18 are all contained in the same projection plane towards the quay.

[0028] The projection plane extends along the transverse Y and elevation Z directions. Thus, the projection plane is substantially perpendicular to the longitudinal direction.

[0029] Each beam extends from the detection system 18 along a respective principal direction.

[0030] The beams form an angular interval from the detection system 18, a first boundary of the angular interval being between 0 and 10 degrees relative to the direction of elevation and a second boundary of the angular interval being between 30 and 45 degrees relative to the direction of elevation.

[0031] The angular interval is included on one side of the detection system 18 with respect to the elevation direction Z, more particularly on the side including the platform 16.

[0032] The detection system 18 emits, for example, beams with a given angular step, typically between 0.25° and 2.5°. The angular step here is a multiple of 0.25°.

[0033] The beams are emitted one after the other, step by step. The projection step 110 is, for example, a scanning step of a laser beam according to the given angular step in the projection plane.

[0034] Each ray emitted by the detection system 18 and reflected back by an obstacle towards the detection system 18 is detected by said detection system 18.

[0035] The detection system 18 then measures the distance between said detection system 18 and the obstacle, according to the time interval taken by the beam to be reflected back by the obstacle.

[0036] In the case of a radius composed of multiple echoes, a measurement is selected as reflecting the dock measurement. For example, the measurement closest to an expected value. Additionally or alternatively, the selected measurement is the one within a given range.

[0037] Alternatively, the selected measurement is the last measurement received for said radius.

[0038] The detection system 18 thus measures, for each beam, the distance between the detection system and the platform measured along the respective principal direction of the beam.

[0039] Each ray, and thus each measured distance, is associated with an angle βn between the corresponding ray and the vertical.

[0040] The detection system 18 is mounted on the vehicle 10 so that a predefined reference radius extends vertically such that the angle βn of said radius is zero. Each of the other radii is located relative to said reference radius, in particular using the number of angular steps between said radius and the reference radius.

[0041] This allows, for example, the profile of the quay to be traced according to said plan based on the detected rays.

[0042] Then, a first part of the measured distances is excluded 130.

[0043] The first part of the distances includes, according to the invention, the measured distances which do not correspond to the upper surface 14, that is to say that the point of the quay returning the ray corresponding to the measured distance is not included in the upper surface 14, and possibly to so-called "aberrant" values ​​as will be described later.

[0044] More specifically, the first part of the distances corresponds only to the measured distances not corresponding to the upper surface 14 and possibly to outliers.

[0045] To exclude measured distances not corresponding to the upper surface of the quay, the method includes, according to the invention, a step of detecting an edge 22 of the quay 16.

[0046] The detection of edge 22 of the quay here includes the comparison of measured distances, the radius reaching edge 22 of quay 16 being the one whose measured distance between the detection system and the quay is the smallest.

[0047] The excluded part not corresponding to the upper surface corresponds to a predefined interval of angles β n whose upper bound is the angle of the radius β 0 reaching the edge 22 of the platform 16.

[0048] Additionally, a value is excluded as an aberrant when it does not meet at least one predefined criterion.

[0049] For example, for each angle corresponding to a measured distance, a range of expected distances is predetermined. When the measured distances are outside their range of expected distances, those measured distances are excluded.

[0050] In one embodiment, the exclusion of so-called outliers is carried out before the exclusion of values ​​not corresponding to the upper surface 14 of the platform 16, so that outliers do not risk distorting the detection of the edge 22 of the platform 16.

[0051] A value may be anomalous when an obstacle such as luggage, a passenger, or a surface defect, typically a platform defect, is present. The detected value corresponds to the value returned by the obstacle itself and not by platform 16, so it is disregarded for calculations related to the platform.

[0052] Then, for each angle whose associated distance is not excluded, the height between the reference point and the platform is calculated from the associated measured distance.

[0053] More specifically, for each angle whose associated distance is not excluded, the height between the reference point and the platform is calculated using the following formula: H cl / q n = D n × cos ∝ 0 + ∝ n − H cl / c with H cl / q n the height between the reference point and the point on the platform reached by the ray, D n the distance associated with the angle, α 0 the angle between the vertical and the ray reaching the edge 16 of the platform, α n the angle between the edge of the platform and the ray corresponding to the measurement and H cl / c , the height between the marker and the detection system.

[0054] Alternatively, the angle βn between the vertical and the radius corresponding to the measurement is known directly, so the height is calculated using the following formula: H cl / q n = D n × cos β n − H cl / c .

[0055] Finally, a general height between the reference point 12 of vehicle 10 and the upper surface 14 of the platform is calculated.

[0056] The said overall height is, for example, calculated by averaging the heights between reference point 12 and the points on platform 16 reached by the rays H cl / q n calculated.

[0057] The calculation of the overall height between said reference point 12 and the upper surface 14 makes it possible in particular to adjust the height of the vehicle 10 in relation to the platform in order to reduce the overall height between the reference point 12 of the vehicle 10 corresponding here to a gap filler and the upper surface 14 of the platform, for example, to facilitate access to the passenger compartment of the vehicle.

[0058] To adjust the vehicle's height, it is possible, for example, to vary the height of the secondary suspension.

[0059] Alternatively, to detect edge 22 of the quay, we calculate H cl / q n for all non-outliers. The variation of the function H cl / q n depending on n, it is possible to detect the edge 22 of the platform. Indeed, for the angles at which the ray intersects the upper surface 14 of the platform 12, the height H cl / q n is substantially constant insofar as the upper surface 14 of a platform 12 near a vehicle 10 is usually substantially flat. For angles at which the radius does not intersect the upper surface 14 of the platform 12, the height H cl / q n varies: more specifically, the closer the radius is to edge 22 of the platform, the higher the height H cl / q n decreases. Edge 22 of platform 16 corresponds to the extent to which the behavior of the function H cl / q n as a function of n evolves from a decreasing function to a substantially constant function or vice versa depending on the direction of sweeping the radius.

[0060] In a second embodiment of the invention, the process comprises the following additional steps: exclusion of a second part of the measured distances, and calculation of a horizontal distance between the vehicle's reference point and the edge of the platform from distances not included in the second part.

[0061] The second part includes the measurements corresponding to the upper surface 14 of the platform 12. This corresponds, for example, to a second angle interval whose lower bound is the angle of the radius reaching the edge 22 of the platform 16.

[0062] Then, for each angle whose associated distance is not excluded, the horizontal distance, more particularly transverse, between the reference point and the quay is calculated from the associated measured distance.

[0063] More specifically, for each angle whose associated measured distance is not excluded, the height between the reference point and the platform is calculated using one of the following formulas: d cl / q n = D n × sin ∝ 0 + ∝ n − d cl / c ou d cl / q n = D n × sin β n − d cl / c with d cl / q n the transverse distance between the reference point and the point on the platform reached by the radius and d cl / c the transverse distance between the reference point and the detection system.

[0064] This allows us to know the transverse distance between vehicle 10 and platform 16.

[0065] This allows us to know, in particular, if vehicle 10 is suitable for platform 16.

[0066] Alternatively or additionally, the transverse distance between the vehicle reference point 12 and the edge 22 of platform 16 in particular is measured, preferably by one of the preceding formulas.

[0067] This allows, for example, adjusting at least one output parameter of the gap filler to allow better vehicle access. For example, the transverse dimension of the gap filler extending from inside the vehicle is adjustable, so that the gap filler is adapted to extend from a greater distance if the transverse distance to the dock is greater.

[0068] Calculating the distance along the elevation direction between a reference point on the vehicle and the top surface of the platform and / or the horizontal distance between a point on the vehicle and the platform allows for adjusting various vehicle parameters, such as the height of the vehicle or the size of a gap filler outside the interior of the vehicle, to allow better vehicle access.

Claims

1. A method for measuring a given distance between a vehicle (10) and an upper surface (14) of a platform (16), the method comprising the following steps: - providing (100) a detection system (18) mounted on the vehicle (10), the detection system (18) being capable of projecting a beam (20) towards the platform (16), - projecting (110) a plurality of beams (20) by the detection system (18), the beams all being comprised in a single projection plane towards the platform (16), - measuring (120), for each beam (20), a distance (Dn) between the detection system (18) and the platform (16) in a respective direction of said beam (20) detected by the detection system (18); the method being characterised by the following steps: - excluding (130) a first part of the measured distances (Dn), the first part comprising the measured distances not corresponding to the upper surface (14), excluding (130) a first part of the measured distances (Dn) comprising detecting an edge (22) of the platform (16) which comprises comparing the measured distances (Dn), each measured distance (Dn) being associated with an angle (βn) between the corresponding beam (20) and the vertical (Z), the excluded first part of the measured distances corresponding to a predefined range of angles, the upper limit of which is the angle of the beam (β0) reaching the edge of the platform, - calculating (140) a vertical distance between a marker (12) of the vehicle (10) and the upper surface (14) of the platform (16) from distances not comprised in the first part.

2. The measurement method according to claim 1, wherein the beam (20) is a laser beam.

3. The measurement method according to claim 1 or 2, wherein the beam reaching the edge (22) of the platform (16) is the beam with the smallest measured distance between the detection system (18) and the platform (16).

4. The measurement method according to any one of claims 1 to 3, comprising a step of excluding a second part of the measured distances (Dn), the second part comprising the measurements corresponding to the upper surface (14) of the platform (16), and a step of calculating a horizontal distance between the marker (12) of the vehicle (10) and an edge (22) of the platform (16) from distances not comprised in the second part, each measured distance being associated with an angle relative to the vertical (βn), the excluded second part of the measured distances corresponding to a range of angles to the vertical, the lower limit of which is the angle of the beam (β0) reaching the edge (22) of the platform (16).

5. The measurement method according to any one of claims 1 to 4, comprising a step of excluding distance values between the detection system (18) and the platform (16), said values not meeting at least one predefined criterion.

6. The measurement method according to claim 5, wherein: - each measured distance is associated with a beam angle, - for each angle, a range of expected distances is predetermined, and - measured distances outside their distance range are excluded during the step of excluding values.

7. The measurement method according to any one of claims 1 to 6, wherein each measured distance is associated with a beam angle, for each angle of which the associated distance is not excluded, a vertical distance ( H cl / q n ) between the marker (12) and the platform (16) is calculated from the associated measured distance.

8. The measurement method according to claim 7, wherein, for each angle relative to the vertical (Z) of which the associated distance is not excluded, the vertical distance between the marker (12) and the platform (16) is calculated with the following formula: H cl / q n = D n × cos α 0 + α n − H cl / c where ( H cl / q n ) is the vertical distance between the marker (12) and the point of the platform (16) reached by the beam, α0 is the angle between the vertical and the beam reaching the edge of the platform (16), αn is the angle between the edge of the platform (16) and the beam corresponding to the measurement and (Hcl / c) is the vertical distance between the marker (12) and the detection system (18).