WEBVTT 00:00.000 --> 00:16.160 We have a very interesting business case, we have the same issue at the SNCF and I am very 00:16.160 --> 00:20.760 happy that my just presented today. 00:20.760 --> 00:24.240 Yes, thank you, Lovic. 00:24.240 --> 00:33.680 So I will give you a bit of an insight on how to process the GNSS position of a train. 00:33.680 --> 00:37.800 I hope everybody knows a little bit what the GNSS position is. 00:37.800 --> 00:44.640 You can think of it as GPS, but in a more general fashion. 00:44.640 --> 00:51.880 So you can also follow this presentation live with this QR code and let me first introduce 00:51.880 --> 00:52.880 myself. 00:52.880 --> 00:59.880 And Mattias, I worked for 15 years in Inferable, and my last day was Friday. 00:59.880 --> 01:12.200 Sorry, I don't know, not sure if that's appropriate. 01:12.200 --> 01:18.080 But yeah, I'm not become a data freelancer, real-way data freelancer, so if anybody is 01:18.080 --> 01:20.720 looking for one. 01:20.720 --> 01:27.280 I really like linked data, that's why I've put this on the slide, linked data, semantic web or 01:27.280 --> 01:30.800 the F, this kind of thing. 01:30.800 --> 01:34.240 And I've been working for Inferable. 01:34.240 --> 01:43.680 So actually I didn't really dare to put the punctuality number on it, but there are a couple 01:43.760 --> 01:55.840 of other numbers, how total punctuality is more as NCB problems than Inferable. 01:55.840 --> 01:58.680 So we have lots of tracks. 01:58.680 --> 02:03.640 Now if you compare numbers of kilometer of track, then sometimes it's confusing, because 02:03.640 --> 02:13.520 I think the Swiss mentioned double track, and here is the total track. 02:13.520 --> 02:21.600 In Main Track, because if you count as well the side tracks, then you have lots more, so 02:21.600 --> 02:28.320 it's difficult to compare the numbers if you don't have a good semantics, of course. 02:28.320 --> 02:33.960 And yeah, we are also getting famous for our deployment of ETCS in Europe. 02:33.960 --> 02:41.600 So almost all the Main Track are equipped with a signaling system from European standard, 02:41.920 --> 02:45.920 ETCS stands for European train control system. 02:45.920 --> 02:50.480 And a lot of people that work at Eferable are actually quite open source minded. 02:53.920 --> 03:03.200 One of them is organizing for them, but the company itself has not yet that open source minded, 03:03.200 --> 03:08.960 but I'm glad to be able to announce that since last year, we are also a partner at open rail. 03:09.920 --> 03:13.600 So I'm quite happy to say that at this conference. 03:15.200 --> 03:23.680 And we are not yet open source minded, but we do have a very big open data platform that's been there for a couple of years. 03:24.320 --> 03:27.040 So feel free to browse in the data sets. 03:31.040 --> 03:37.600 I read this morning, and I said, I'm so happy I need to put this on a slide and present it to you as well. 03:39.920 --> 03:43.040 Peter Colpart is a professor at at the University of Gantt. 03:44.480 --> 03:49.040 He posted this this morning, and he said, okay, I read through the government agreement. 03:49.760 --> 03:52.160 Yes, Belgium almost has a government. 03:56.400 --> 03:59.280 And he says, okay, it is really good for our open data. 04:00.160 --> 04:07.200 And I was very happy because open data is very nice, but it's also very good for open linked data. 04:07.840 --> 04:10.400 And it's also mentioned in the government agreement. 04:11.280 --> 04:20.160 So if you don't know what it is, I would suggest to look it up and to gain some skills in that area. 04:21.120 --> 04:25.520 And if you would like some pointers, then feel free to come to me after the presentation. 04:28.080 --> 04:31.760 So back to on track, back on the topic. 04:32.640 --> 04:38.000 Why do we need to do this thing with post processing positions? 04:38.800 --> 04:46.640 Well, we have this measurement vehicles, and we need them to go measure the tracks and see if they are still in the correct position. 04:46.960 --> 04:50.560 If they are not in wrong with them, something that we need to intervene in. 04:51.840 --> 04:54.160 So they drive around everywhere in the network. 04:55.200 --> 05:01.520 And yeah, if you want to process that, you need a position, you need to put it on a chart. 05:01.760 --> 05:07.840 And then detect the issues and send a correct position to your technicians to go fix the issue. 05:09.120 --> 05:14.320 And if you want to do some predictive maintenance, so that means I want to see what happened last year, 05:14.320 --> 05:18.320 and the year before, and then the year before, and that's a kind of short timeline. 05:18.880 --> 05:25.440 Well, yes, you can do that, but for a specific position, if it's wrong in a meter, 05:26.320 --> 05:32.400 last year a meter to that side, and then the next year a meter to that side, it can get a problem. 05:32.400 --> 05:36.880 So you need a very accurate position in order to do a trend line analysis. 05:39.600 --> 05:42.000 And it can get quite complicated. 05:43.680 --> 05:46.720 Lots of switches, lots of tracks. 05:46.720 --> 05:51.280 So what tools do we have? 05:53.200 --> 05:55.120 Where we have this measurement train? 05:55.120 --> 06:00.400 Well, the first thing you do is you install a GPS system on it GNSS receiver. 06:01.520 --> 06:06.560 And you try to make this as precise as possible in real time. 06:06.560 --> 06:11.760 You try to get some corrections happening, and that is what's RTK stands for. 06:12.720 --> 06:14.960 It's actually very simple RTK. 06:14.960 --> 06:21.680 You put a GPS somewhere, and you measure very precisely the position of that location. 06:22.400 --> 06:27.680 And at the same time, you're going to see what the singles say of your GPS satellites, 06:28.080 --> 06:31.680 or they say I'm okay, I'm a meter away, but that's not true, I know I'm here. 06:31.680 --> 06:34.480 So the correction needs to be a meter in that direction. 06:35.040 --> 06:39.280 So that's the kind of correction you can do with a GPS. 06:42.720 --> 06:49.120 But one issue is you need to have some sky, some clear sky. 06:50.960 --> 06:55.200 It doesn't need to be perfect all the time, but if you have lots of buildings, 06:55.200 --> 06:58.080 and a tunnel, and so on, then it can get quite complicated. 07:00.720 --> 07:04.720 I have a question, but the people, for me, for a bell that they are sitting here cannot answer. 07:05.680 --> 07:17.680 I didn't ask my question yet, but you already gave me this question. 07:17.680 --> 07:22.080 So I was going to ask the question, what is the difference between UTC time and GPS time, 07:22.080 --> 07:26.640 and I got the right response over there? Do you know the number of leap seconds? 07:28.640 --> 07:30.400 Yes, it's 18, so about 20, yes. 07:31.360 --> 07:38.240 Well, I can guarantee you if you're making some kind of system that post-processes GPS data, 07:38.240 --> 07:46.480 and you need to link it to images or other measurements, and they don't line due to this, 07:47.040 --> 07:50.720 due to you not knowing that there are leap seconds, then you can get very confused, 07:50.720 --> 07:53.440 and takes a lot of time to try to fix it. 07:54.000 --> 07:59.520 And some people need to do it a second time. 08:06.000 --> 08:11.600 Secondly, we have another tool that helps us to do positioning, 08:11.600 --> 08:14.720 and that is more relative-based positioning. 08:14.720 --> 08:18.160 So if we are in that tunnel, and we don't have a clear sky, 08:19.120 --> 08:27.360 well, we can still remember our last position, and try to measure the changes in direction that we have. 08:28.400 --> 08:35.920 And that is the EMU, IMU, inertial measurement unit, it's an accelerometer, a very expensive accelerometer. 08:37.840 --> 08:42.240 And the more expensive you go, the more precise it is, and the more precise it is, 08:42.240 --> 08:45.840 the longer you can travel in a tunnel without too much of an error. 08:45.920 --> 08:49.280 Because it's relative, the smallest error you have, 08:49.280 --> 08:54.640 well, the longer you go without anything that fixes the error, the bigger the error. 08:56.000 --> 08:58.960 So, and the second thing that we can use is an automator, 09:00.080 --> 09:02.880 that's everybody knows what it is. 09:05.440 --> 09:11.840 Yes, it's the wheel. So, you will turn, and you measure the distance that you travel. 09:11.920 --> 09:17.680 Every car has it to display the speed as well, and we also use that for positioning. 09:20.880 --> 09:26.800 Oh yeah, and a normal GNSS receiver, you can actually just plug and play, plug everything in, 09:26.800 --> 09:33.520 and it will use all these things that I just mentioned, to calculate a very precise absolute location. 09:33.600 --> 09:43.360 A third thing, since we are in real-way, in the TREX, we have these boxes, 09:44.640 --> 09:53.200 or we have crocodiles or other boxes, they detect trains, and the train can also use them 09:54.000 --> 10:01.360 to detect where it is, because if you have a database that has these IDs of these objects, 10:01.680 --> 10:05.120 and you pass over it, then you know for sure, okay, I'm over there. 10:06.800 --> 10:10.640 So, that's the third thing that we can use in order to improve positioning. 10:15.600 --> 10:22.240 So, absolute relative and detection systems, what are we going to do with all of that? We are going to 10:22.240 --> 10:30.240 give it an information, at least, at our almost open-source train positioning library. 10:31.440 --> 10:37.760 So, we gather the data, we put it into that library, it starts working, and it gives us a 10:37.760 --> 10:44.560 track position at the end. A topological position, you have heard the word a couple of times before 10:44.560 --> 10:50.720 topology, well here we also going to use topology, but not on the micro level where your stations 10:50.720 --> 10:56.160 as notes, but on a micro level, the smallest level switches and trails. 10:58.480 --> 11:05.280 And yeah, it's not yet open-source, because it's actually a lot more work than you would think, 11:05.280 --> 11:11.200 if something was close source, in order to make it open-source, it's a little bit more work 11:11.200 --> 11:20.000 than you would think before. So, let's see, we have a train driving on track A, 11:20.000 --> 11:29.200 and in that direction to the left. And the blue points are the GPS coordinates that our GPS 11:29.200 --> 11:37.200 receiver is outputting. As you can see, there is already a bit of an error, and there is a switch 11:37.200 --> 11:45.760 in the middle. Now, let me first simplify a little bit this visualization. Let me combine both rails 11:45.840 --> 11:55.360 into one, to have this as a more schematic design with a center axle axis of the track. 11:57.520 --> 12:03.680 And well, what can we do to now post-process the coordinates? 12:05.360 --> 12:11.120 The first thing, the most simplest idea we can do is we can say, okay, let's just project 12:12.000 --> 12:20.240 those blue dots onto the closest track. And then we would get this result, the green dots. 12:20.960 --> 12:28.000 And as you can see, in the switch, it's not very good, because, well, yeah, we kind of jump 12:28.000 --> 12:32.000 a train from one track to the other. It needs to take a switch, a proper way, 12:33.040 --> 12:37.360 or you would need to have a lot of willing passengers on the train to lift it up and put it on. 12:38.000 --> 12:42.000 And we all know that in Belgium, passengers are horrible. 12:50.000 --> 12:57.600 So, let's work the problem with a bit further. Welcome navigability. So, we heard the topic before 12:57.600 --> 13:07.440 topology. Well, here topology, we have also notes the switches and things that connect 13:07.440 --> 13:13.680 switches and tracks trails. And you cannot go from one trail to the other just by that. So, 13:13.680 --> 13:20.000 you cannot go from A2 to S1 without passing by A1 and then reversing direction. 13:20.960 --> 13:29.440 So, we can get this graph, this connectivity graph, and we can use that in our navigation 13:29.440 --> 13:34.480 system, in our post processing system. So, applying this principle, 13:37.520 --> 13:43.680 gets us that the green dots are where they need to be. So, we are happy. Right? 13:43.680 --> 13:54.640 Not yet. Maybe if we go in the other direction, we will have a problem. So, if the train is driving 13:54.640 --> 14:03.120 the other direction, then the navigability is going to give us more issues. So, it's so right, 14:03.120 --> 14:08.960 we can use it, we can get a separate, but it's not yet perfect. So, let's see what we can do with 14:08.960 --> 14:19.520 those beacons, train detection systems. This is a typical view of a traffic operator. 14:20.720 --> 14:28.160 And it's topological. So, you see that the switches are there and you see the trains running. 14:28.160 --> 14:36.480 So, the red is in fact the current location of a train and the green is the plant route that the 14:36.640 --> 14:44.240 train will take. So, this information exists, this is available at least inside our company. 14:44.240 --> 14:50.800 So, we can use it to improve the location a little bit better. So, that's actually what's 14:52.080 --> 14:57.520 that train positioning library is is doing. It will first calculate the train path. 14:58.480 --> 15:06.400 It will first try to find and optimize the way that a train run. And then after that, after we 15:06.400 --> 15:12.640 figure out the train path, then we will go project the GPS coordinates onto it. 15:14.640 --> 15:21.280 And we do that with whatever data is available. So, if at a certain point we don't have 15:21.440 --> 15:27.600 information about a single-ing system, then we can use the GPS locations as well to calculate a 15:27.600 --> 15:39.840 train path. And any gaps that exist, well, some of them are easy to solve. So, from here, 15:41.680 --> 15:49.680 if you have a train running on the red line over there and you also have a detection over here, 15:50.400 --> 15:59.120 well, you don't need to be psychic to know that a train probably went in this direction. 16:00.480 --> 16:06.320 And the same goes for this trail. It was missing in the train detection system. 16:06.320 --> 16:11.920 Noting is perfect. Rest assured, the signaling system is perfect. You will not get any accidents, 16:11.920 --> 16:17.760 but the data behind it is not always the logging data is not always so precise. 16:18.240 --> 16:26.880 But then on the other side, over here, it's a bit more complicated. You will need some additional 16:26.880 --> 16:33.360 data to actually know what the train has done. Although we can be quite sure, looking at that, 16:33.360 --> 16:38.480 it just goes straight ahead. But you never know if info about those works over there and then 16:38.640 --> 16:55.280 reroute the train. Okay, so, for them, 2023. First time this railway track was organized 16:56.560 --> 17:06.880 and at the time RCMDX was presented and was made open source. RCMDX is rail condition monitoring, 17:06.960 --> 17:14.080 data exchange. It's an exchange format. Very interesting. If you ever want to exchange 17:14.080 --> 17:22.000 data in a very compact way, a binary way, look it up. And at the time I said, okay, 17:22.000 --> 17:29.920 info bell will join SBB who introduced RCMDX in the project and we will try to implement it as well. 17:30.160 --> 17:40.800 At the moment, one possible extension of the project of the train positioning library could be 17:40.800 --> 17:49.920 to read and write to that RCMDX file. So, it's the file that is transmitted off the measurement 17:49.920 --> 17:56.960 train. It's that contains the raw data and then we can say, okay, we put that library besides it 17:57.120 --> 18:03.760 and we're going to take the data out, process it and put it back in. And then you still have 18:03.760 --> 18:12.080 a standard format to exchange your data. And at the same time, well, all the topology data that 18:12.080 --> 18:16.800 I talked about that you would need for the train positioning library. Well, you could also imagine 18:16.800 --> 18:24.640 a connector with something like Rint. Rint is the register of infrastructure. It's one of those 18:24.640 --> 18:32.960 TSI things that we heard before, as well, the moment TSI telemetics. All those TSI's have data requirements 18:32.960 --> 18:41.520 and Rint is one of those products that combine all the data. Rint will be hopefully next year, 18:42.800 --> 18:50.640 database which is in linked data as well, which is complete of micro topology information from all 18:50.640 --> 18:58.240 inform managers. So, it's going to be a very important source of data, also for projects like these. 19:02.720 --> 19:10.240 And to wrap up, I, in my description of the project, I also promised to give you a little bit 19:10.240 --> 19:17.600 of an insight on how we also use open source hardware and information. So, in a measurement train, 19:18.560 --> 19:24.160 you usually have some of the driving the train, but also somebody who is going to push the buttons 19:24.160 --> 19:29.280 to say, okay, now the measurement system needs to be turned on. Now we are driving this direction 19:29.280 --> 19:36.480 on this line as well. We automated all of that for the positioning system. So, the positioning 19:36.480 --> 19:43.360 measurement system. And we did that with the Raspberry Pi. It's very simple with some shell 19:43.360 --> 19:49.360 scripts, actually, not really, we didn't even use Python for it. And it's, it worked flawlessly 19:49.360 --> 19:59.040 until at one time it became a black lump of silicon when some safety transformer burnt out. 19:59.040 --> 20:02.560 And yeah, but that's not the issue of the Raspberry Pi. 20:03.120 --> 20:14.960 And yeah, that's to prove. And this is a picture of the cabinet where it's in. And yeah, 20:14.960 --> 20:21.360 you can see it's in, hello over there. There is a shield on it to connect it to other 20:21.520 --> 20:26.720 sources as well. So, thank you very much for listening. 20:34.160 --> 20:37.200 And if you have some questions, I'll be happy to answer them. 20:37.200 --> 20:55.040 Okay, so the question is will it be open sourced? Yes, it will. That has been decided. It's part 20:55.040 --> 21:01.280 of the reason why, well, if we're about joined open rail and now we have to put some, we need to 21:01.360 --> 21:06.320 eat a pudding, putting as well, of course, we need to join the community and give something back. 21:06.320 --> 21:13.120 And yes, some people might be, other people might be able to tell when it's going to happen. 21:13.920 --> 21:20.880 But I hope that it would have been before this day, but it has a bit of delay, which is not normal for 21:20.880 --> 21:24.880 trains. 21:24.960 --> 21:33.840 Yes? Yes? How did you get around regulatory or threat tape making it's called threat 21:33.840 --> 21:39.120 very high in the country? Because I have heard those, they're very self-acquisited. 21:39.120 --> 21:43.920 And often the hardware is very ancient and very crappy because of all the threat tape 21:43.920 --> 21:50.320 to glory, years and very expensive clarification. So, I'll put it get around that. 21:51.280 --> 21:55.440 That's a very good question. So, how did we get around to the threat tape involving installing a 21:55.440 --> 22:01.280 Raspberry Pi on a measurement train? 22:04.400 --> 22:07.280 Next question. 22:07.280 --> 22:32.000 I think a large problem because it doesn't do it in the passenger train, so it's okay. 22:37.600 --> 22:39.760 This is safety. That's why it's. 22:39.760 --> 22:47.680 Yeah, it's all the safety components, but you also have fire regulations as on that might apply. 22:56.080 --> 23:05.120 Does it have its own power supply? It's connected to a power converter, USB converter, let's say, 23:05.120 --> 23:15.120 inside the cabinet. Well, it's not USB plug. It's a real transformer meant for the railway vehicles, 23:15.120 --> 23:21.840 of course, yeah, which out with five volts, 25, 24, 12 and so on. 23:27.840 --> 23:33.200 Those are really signaling begins. So, they are part of the signaling system, they are connected to the 23:33.280 --> 23:40.000 signals and to the interlocking. And yeah, it's, I'm not sure what the transmission 23:40.720 --> 23:48.000 technology is. It's not like once they're using the tunnel and they're either to the train, 23:48.800 --> 23:58.640 if it's used. It's very, yeah. Well, no, but it's at the 27 megahertz. So, get your SDR on. 23:59.040 --> 24:03.040 Yeah. 24:17.040 --> 24:24.080 Well, and so the question is, if, when we travel over a beacon, do we get a precise position from the beacon? 24:24.080 --> 24:28.560 Or do we know the precise moment that the train travels across the beacon? 24:28.560 --> 24:31.120 Do we know the precise moment that train traveled over the beacon? 24:34.960 --> 24:41.840 For this project, it's not important. But we do know that precise moment, but you can also 24:44.720 --> 24:50.240 refresh the question a bit. And the problem with the question is, your detection system of the beacon 24:50.240 --> 24:56.960 is somewhere under the train and it's not at the same place as the GPS antenna. So, you will need 24:56.960 --> 25:02.640 to take into account that distance and the speed that you're driving and the orientation of your vehicle 25:02.640 --> 25:15.520 in order to figure out to place at the time. But in this case, the exact position in the 25:15.520 --> 25:21.440 longitudinal sense is not so important. It's knowing on which track you are or trail you are, 25:21.440 --> 25:23.520 that is important. 25:23.520 --> 25:32.800 Just mention the TECA system, after TECA system, and you just talk about the genesis system, 25:34.080 --> 25:39.120 did you try the TECA which is very precise? 25:39.120 --> 25:48.240 Sorry. So, the question is, we use GNSS and RTK, and which is more precise? 25:48.240 --> 25:59.840 So, adding RTK to a GNSS solution, you first need GNSS and then you can add RTK and it will improve 25:59.840 --> 26:08.080 your positioning because it will decrease the environmental issues that you have with GNSS. 26:08.640 --> 26:18.800 So, if you, I explained before that RTK works by having a base station, somewhere near where 26:18.800 --> 26:26.720 you're measuring and that base station is most exactly its location. But it's also measuring 26:26.720 --> 26:35.440 the GPS signals and can then say, okay, the GPS signal that we get are distorted in this way 26:35.520 --> 26:42.560 and then you can add corrections. The precise position of your measurement vehicle will depend 26:42.560 --> 26:50.720 on more than just adding RTK to improve the solution you, if you're in a tunnel or in an area 26:50.720 --> 26:59.600 with trees or some overhead constructions, then you have more distortions than the base station 26:59.680 --> 27:03.120 you will see as distortions. So, you will not be able to correct for those. 27:05.760 --> 27:12.320 Yeah, but adding RTK is always a good idea. It's in Belgium, it's free. You have, 27:13.440 --> 27:20.000 well, it depends on how you use it. But you have flapples, well-core, if people wonder 27:22.400 --> 27:26.160 and see that at the same time, info about things about building its own RTK network 27:26.800 --> 27:42.080 to then be able to sell it to ZNCB. Yeah, it's more for the safety, the people that work that we are 27:42.080 --> 27:50.160 going to, info about is also busy but improving worker safety and one of the things that they want 27:50.160 --> 27:57.600 to improve on is alerting people when they are going inside the dangerous area and that is 27:57.600 --> 28:06.640 by GPS taking the people and adding RTK is helping making it more precise. Okay, I see my time is up 28:06.640 --> 28:10.560 so if there are any more questions and please feel free later.