Guideway mounted vehicle localization and alignment system and method

Patent metadata

Field	Value
Publication number	US-11254338-B2
Application number	US-201816143035-A
Country	US
Kind code	B2
Filing date	Sep 26, 2018
Priority date	Sep 27, 2017
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

A system comprises a first sensor on a first end of a vehicle and an on-board controller coupled to the first sensor. The first sensor is configured to detect a radio frequency (RF) signature of a marker along a guideway. The first sensor is a radar detection device. The on-board controller is configured to determine a first position of the vehicle on the guideway or a first distance from the position of the vehicle to a stopping location along the guideway based on at least the RF signature received from the first sensor. The marker is a metasurface plate comprising a first diffused element, a first retroreflector element, a first absorbing element and a second diffused element between the first retroreflector element and the first absorbing element.

First claim

What is claimed is:

1. A system comprising:
a first sensor on a first end of a vehicle, and configured to detect a radio frequency (RF) signature of a marker along a guideway, wherein the first sensor is a radar detection device; and
an on-board controller coupled to the first sensor, and configured to determine a first position of the vehicle on the guideway or a first distance from the first position of the vehicle to a stopping location along the guideway based on at least the RF signature received from the first sensor;
wherein the marker is a metasurface plate comprising:
a first diffused element;
a second diffused element;
a third diffused element;
a first retroreflector element between the first diffused element and the second diffused element; and
a first absorbing element between the second diffused element and the third diffused element.

2. The system of claim 1 , wherein the system further comprises:
a second sensor on a second end of the vehicle, and configured to detect another radio frequency (RF) signature of the marker along the guideway,
wherein the second sensor is another radar detection device,
the second end of the vehicle is opposite from the first end of the vehicle, and
the on-board controller is further coupled to the second sensor, and further configured to determine a second position of the vehicle on the guideway or a second distance from the second position of the vehicle to the stopping location along the guideway based on the another RF signature received from the second sensor.

3. The system of claim 2 , wherein
the marker is located at the stopping location; and
the on-board controller is further configured to:
compare the first distance with the second distance;
determine that the first sensor and the second sensor are not faulty, if the first distance does not differ by more than a predefined tolerance from the second distance; and
determine that one of the first sensor or the second sensor is faulty, if the first distance differs by more than the predefined tolerance from the second distance.

4. The system of claim 2 , wherein the on-board controller is further configured to:
compare the first position with the second position;
determine that the first sensor and the second sensor are not faulty, if the first position does not differ by more than a predefined tolerance from the second position; and
determine that one of the first sensor or the second sensor is faulty, if the first position differs by more than the predefined tolerance from the second position.

5. The system of claim 2 , wherein the on-board controller is further configured to determine a length of the vehicle comprising:
determining a relative velocity of the vehicle between the first sensor or the second sensor and the marker;
determining a first time the first sensor of the vehicle passes a first portion of the marker;
determining a second time the second sensor of the vehicle passes the first portion of the marker, the first portion of the marker being a starting point of the metasurface plate or an ending point of the metasurface plate;
determining a time difference from the first time and the second time; and
determining the length of the vehicle based on the time difference and the relative velocity of the vehicle.

6. The system of claim 1 , wherein the on-board controller is further configured to:
determine a start point of the metasurface plate based on a first sequence of symbols associated with a first portion of the metasurface plate; and
determine an end point of the metasurface plate based on a second sequence of symbols associated with a second portion of the metasurface plate.

7. The system of claim 6 , wherein the on-board controller is further configured to:
determine a leading end of the vehicle and a trailing end of the vehicle based on an order of the sequence of symbols associated with the first portion of the metasurface plate or the second portion of the metasurface plate.

8. The system of claim 1 , wherein the on-board controller is further configured to determine at least one of the following:
a distance from the first sensor to the marker;
a relative velocity of the vehicle between the first sensor and the marker; or
an angular position of the first sensor relative to the marker.

9. The system of claim 1 , wherein the metasurface plate further comprises:
a fourth diffused element;
a fifth diffused element;
a sixth diffused element;
a second absorbing element between the fifth diffused element and the sixth diffused element; and
a second retroreflector element between the fourth diffused element and the fifth diffused element;
wherein the first diffused element is on a first end of the metasurface plate, and the sixth diffused element is on a second end of the metasurface plate opposite the first end of the metasurface plate.

10. The system of claim 1 , wherein the vehicle is configured to move along the guideway, and the marker is on the guideway.

11. The system of claim 1 , wherein the vehicle is configured to move along the guideway, and the marker is on a wayside of the guideway.

12. The system of claim 1 , wherein the first sensor is configured to measure an echo signal from the metasurface plate, and the RF signature includes a set of signal to noise ratios (SNRs) of the echo signal.

13. A system comprising:
a marker along a guideway, the marker including a metasurface plate comprising:
a first portion having a first retroreflector element;
a second portion having a second retroreflector element;
a third portion having a third retroreflector element;
a first absorbing element between the first retroreflector element and the second retroreflector element; and
a first diffused element between the first retroreflector element and the first absorbing element;

a first sensor on a first end of a vehicle, and configured to detect a radio frequency (RF) signature of the marker, wherein the first sensor is a radar detection device;
a second sensor on the first end of the vehicle, and configured to detect another signature of the marker, wherein the second sensor is a camera, a laser imaging detection and ranging (LIDAR) device or an infrared radiation (IR) sensor detection device; and
an on-board controller coupled to the first sensor and the second sensor, and configured to determine a position of the vehicle on the guideway or a distance from the position of the vehicle to a stopping location along the guideway based on information received from the first sensor and the second sensor, the information including the RF signature and the another signature.

14. The system of claim 13 , wherein the on-board controller configured to:
determine the position of the vehicle on the guideway based on information received from the first sensor and the second sensor comprises the on-board controller being configured to:
determine a first position of the vehicle on the guideway based on information received from the first sensor; and
determine a second position of the vehicle on the guideway based on information received from the second sensor; or

determine the distance from the position of the vehicle to the stopping location along the guideway based on information received from the first sensor comprises the on-board controller being configured to:
determine a first distance from the position of the vehicle to the stopping location along the guideway based on information received from the first sensor, the marker being located at the stopping location; and
determine a second distance from the position of the vehicle to the stopping location

Assignees

• Thales Canada Inc

Inventors

• Green Alon
• Kinio Walter
• Timmermans Peter

Classifications

• G01S13/88

  Radar or analogous systems specially adapted for specific applications (electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00) · CPC title

• H01Q1/3225

  Cooperation with the rails or the road · CPC title

• G01S17/06

  Systems determining position data of a target · CPC title

• G01S13/75

  using transponders powered from received waves, e.g. using passive transponders {, or using passive reflectors} · CPC title

• B61L25/041

  using reflecting tags · CPC title