# US 2021/0276601 A1 · Method and controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0276601 A1 - Document ID: US20210276601A1 - Status: Published application - Kind: A1 - Application number: 16/811,244 - Filed: 2020-03-06 - Published: 2021-09-09 - Earliest claimed: 2020-03-06 - Assignees: Alstom Transport Technologies - Applicants: ALSTOM Transport Technologies - Inventors: Nenad MIJATOVIC; Jeffrey FRIES; Jesse HERLOCKER - Web page: https://patentgrep.com/patent/US20210276601A1 ## CPC - B61L 25/026: {Relative localisation, e.g. using odometer} - B61L 1/185: {Use of direct current} - B61L 25/025: {Absolute localisation, e.g. providing geodetic coordinates} - G08G 1/123: indicating the position of vehicles, e.g. scheduled vehicles; {Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, trams}(transmission of navigation instructions to vehicles G08G1/0968) - B61K 9/08: Measuring installations for surveying permanent way - G06F 2218/14: by matching peak patterns - B61L: GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC (brakes or auxiliary equipment B61H, B61K; point or crossing construction E01B) - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) - B61K: AUXILIARY EQUIPMENT SPECIALLY ADAPTED FOR RAILWAYS, NOT OTHERWISE PROVIDED FOR - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Disclosed is a method for determining the relationship between a track-circuit current signal and a railway vehicle location, including: sending, by a track circuit, current signal across a railway track block; measuring the current signal for different railway vehicles running successively on the railway track block; aligning the measured current signals and calculating a reference curve as the average value of all the aligned curves by using a Dynamic Time Warping algorithm, this reference curve representing the relationship between the track-circuit current signal and the railway vehicle location on the railway track block. ## Claims ### Claim 1 Method for determining the relationship between a track-circuit current signal and a railway vehicle location, comprising sending, by a track circuit, current signal across a railway track block, measuring the current signal for different railway vehicles running successively on the railway track block; aligning said measured current signals and calculating a reference curve (R) as the average value of all the aligned curves by using a Dynamic Time Warping algorithm, this reference curve (R) representing the relationship between the measured track-circuit current signal and the railway vehicle location on said railway track block. ### Claim 2 (depends on 1) The method of claim 1, wherein the inputs of the Dynamic Time Warping algorithm are a plurality of current signals measured for several railway vehicle move sequences across the railway track block and a maximum number of algorithm iterations (N), wherein each current signal measured for an individual (ith) railway vehicle move sequence (Ii) contains transmitted current peak values (I(i,j)) of a plurality of samples of said measured track-circuit current signal. ### Claim 3 (depends on 2) The method of claim 2, wherein the reference curve (R) contains a plurality of elements (r1, r2, . . . , rp). ### Claim 4 (depends on 3) The method of claim 3, comprising the steps of: a) initializing (2) the elements of the reference curve (R) by randomly selecting one current signal measured for an individual railway vehicle move sequence; b) for each current signal measured for an individual railway vehicle move sequence performing (5) the Dynamic Time Warping algorithm between the current signal and the reference curve; c) for each element (pth) in) the reference curve, associating (6) an appropriate set of elements from the current signal measured for an individual railway vehicle move sequence with said element (pth) in the reference curve; d) updating (8) each element (pth) of the reference curve by calculating the average of all associated elements found in step c); e) repeating steps a) to d) by initializing (2) the elements of the reference curve (R) with the elements of the updated reference curve calculated at step d), up to the maximum number of algorithm iterations (N). ### Claim 5 (depends on 1) The method of claim 1, further comprising the steps of determining a confidence interval and/or a safety margin using a bootstrap percentiles method. ### Claim 6 (depends on 5) The method of claim 5, comprising the steps of: collecting (100) transmitted current values measured for N railway vehicle moves, thus obtaining a railway vehicle move data set; creating (102) a plurality of bootstrap railway vehicle move datasets (102′, 102″, 102′″, . . . , 102B) of size N by resampling the original railway vehicle move data set with a replacement set, wherein resampling is performed by random selecting railway vehicle moves from the original set with probability of 1/N; calculating (104) the reference curve (104′, 104″, 104′″, 104B) for each bootstrap dataset. ### Claim 7 (depends on 6) The method of claim 6, comprising the step of: determining, on the basis of the reference curves (104′, 104″, 104′″, 104B) obtained for each bootstrap dataset, using a predetermined percentile interval, lower Ri(Tx) and upper Ru(Tx) confidence interval values for predefined measured track-circuit current values Tx. ### Claim 8 (depends on 7) The method of claim 7, comprising the step of: setting (106) a safety margin in function of the mean value of the lower (Ri(Tx)) confidence interval values. ### Claim 9 (depends on 1) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 1. ### Claim 10 (depends on 9) Track circuit comprising a controller according to claim 9. ### Claim 11 (depends on 2) The method of claim 2, further comprising the steps of determining a confidence interval and/or a safety margin using a bootstrap percentiles method. ### Claim 12 (depends on 3) The method of claim 3, further comprising the steps of determining a confidence interval and/or a safety margin using a bootstrap percentiles method. ### Claim 13 (depends on 4) The method of claim 4, further comprising the steps of determining a confidence interval and/or a safety margin using a bootstrap percentiles method. ### Claim 14 (depends on 2) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 2. ### Claim 15 (depends on 3) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 3. ### Claim 16 (depends on 4) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 4. ### Claim 17 (depends on 5) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 5. ### Claim 18 (depends on 6) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 6. ### Claim 19 (depends on 7) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 7. ### Claim 20 (depends on 8) Controller for determining the relationship between a track-circuit transmitted current signal and a railway vehicle location on a railway track, the controller being adapted to be connected to a track circuit arranged to send a current signal across a railway track block on which different railway vehicles are running successively, the controller being arranged to perform the method according to claim 8.