[HN Gopher] Show HN: Tracking my local bus with a RaspberryPi
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Show HN: Tracking my local bus with a RaspberryPi
Author : fersarr
Score : 170 points
Date : 2022-11-04 10:44 UTC (12 hours ago)
(HTM) web link (purplehoisin.com)
(TXT) w3m dump (purplehoisin.com)
| rakoo wrote:
| This is _exactly_ what Web Out Of Browsers (https://woob.tech/)
| aims to do: get information stored in websites, and offer a
| programmatic way to use them.
|
| There is an application called woob travel that shows timetables:
| https://woob.tech/applications/travel. It plugs back ends, each
| of which is a website. Once parsed, the data is programmatically
| available for anything.
|
| Bonus point for OP: it is all written in python !
| allenbina wrote:
| I'm amazed at my own programming progress over the past 10 years.
| I used to read these posts in awe of how people knew how to do
| such fascinating things that seemed so magical to me. 5 years ago
| I got myself a raspberry pi and an Arduino starter kit and just
| started playing around with them. I learned python by practicing
| on leetcode and other sites and I'm able to recognize a lot of
| libraries and patterns in his code. It's a bit less magical but I
| have a much more refined appreciation for posts like this.
| sergiotapia wrote:
| Next step is realizing that most code is a liability and you
| will begin to loathe anything "smart". I'm at this step right
| now. I'm curious if any graybeard out there can share what the
| next step is.
|
| I don't even want smart electrical outlets.
| seanw444 wrote:
| It's the natural progression I think.
|
| - Step 1. Know nothing about computer technology, and think
| it's magic.
|
| - Step 2. Begin to learn about computer technology, and think
| it's fascinating.
|
| - Step 3. Learn a lot about computer technology, and lose
| your trust in most developers/engineers that aren't yourself,
| and avoid said technology.
| beoberha wrote:
| This is extremely accurate in my experience (besides
| trusting only myself, I don't even trust myself). In
| general, the engineers I work with are much less "techie"
| than a lot of people I know outside of work.
| [deleted]
| sowbug wrote:
| Re future work "It bugs me that I'm fetching this information
| every 30 seconds even though most of the time I won't use it":
|
| Take a look at Home Assistant, which runs nicely on the same
| hardware. You get a reasonably capable platform that knows when
| you're home and can be told a schedule, so you can then limit the
| checks to times when you'll actually need to know.
|
| https://www.home-assistant.io/
| BrandoElFollito wrote:
| I think that the platform is more than reasonably capable.
|
| Either your usage fits into one of the zillions integrations
| (especially via HACS), or you can easily build something
| alongside with pyscript.
|
| The state machine in HA is excellent, I use it for unrelated
| projects instead of a bus or something like that.
|
| The UI is good and is getting better. I wrote years ago my own
| dashboard (that uses data from HA, among others) but I am
| slowly getting used to the idea that I may simply replace it
| with a full-screen page from HA's UI (especially when I manage
| to have widgets written in Quasar/Vue running correctly)
| [deleted]
| WaitWaitWha wrote:
| For a minute, before following the link, I was thinking 'why not
| just look up the schedule? And, did you leave a RasPi on a bus?!
| Those things are like $200 now! Maybe you can get it back at the
| bus depot...'
| [deleted]
| nashashmi wrote:
| What do you mean 200$
| bombolo wrote:
| They are a bit hard to find at the moment.
| michaelt wrote:
| If you want a new raspberry pi 4 8GB today, you basically
| have to buy from a scalper at a cost of around $200 [1]
|
| Or you can try to monitor https://rpilocator.com more than
| the scalpers do, and you might be able to get one for $100
| instead.
|
| [1] https://www.ebay.com/sch/i.html?_from=R40&_trksid=p238005
| 7.m...
| [deleted]
| fersarr wrote:
| :) We could hide it inside a bus and make a geolocation game!
| goatcode wrote:
| In some areas, it would be necessary to somehow install
| trackers on your busses that you use. Depending on the
| jurisdiction, I've had to deal with busses either being
| possibly 10 minutes early, or missing their stop time by up to
| half an hour.
| geraldwhen wrote:
| This is a good reason to stop using busses, not add tracking.
| goatcode wrote:
| That is what I myself ended up doing :)
| ageitgey wrote:
| I made a similar thing in London as well:
| https://twitter.com/ageitgey/status/1383381051154726920
|
| The TfL API is really pretty good - no need to scape pages.
| sorenjan wrote:
| While this is a nice project, it's basically just simple web
| scraping. I was hoping for something a bit more interesting, like
| decoding the radio signals for the bus stop displays[0] and using
| that data. If it's available from an API it of course makes more
| sense to use that though.
|
| [0] https://www.windytan.com/2013/11/decoding-radio-
| controlled-b...
| unnouinceput wrote:
| Or setup a RPi camera, with OpenCV and recognize your bus while
| it's around the corner 2 streets before coming to the stop so
| you know you'll have a full minute until it gets there. I mean
| a 30 meters pole on top of your house isn't something that hard
| to do. And the programming of that is so much more fun that
| just the web scrapping. Plus is actually more accurate than a
| web scrapping that can have de-synchronizations between that
| and the real bus.
| [deleted]
| jaimehrubiks wrote:
| If only the Chicago CTA api was close to reliable... It's well
| known for the ghost buses and disappearing trains. However we
| wouldn't probably need to call Apis, just refreshing their
| website would work as it's similar to OP's (or Google maps or any
| other using the apis).
|
| The best solution here would be to secretly implant a RPI zero
| with gps into every bus
| fersarr wrote:
| > The best solution here would be to secretly implant a RPI
| zero with gps into every bus
|
| Ha and then you can also create an API for others with that
| data :)
| seanw444 wrote:
| Now _that_ would be cool. Although costly, if it were
| discovered.
| alex_suzuki wrote:
| > The best solution here would be to secretly implant a RPI
| zero with gps into every bus
|
| From the title, this was what I was actually expecting the
| article to be about. :-)
| dssagar93 wrote:
| I feel lucky that in India we have an app to track the live
| location of all the buses. I almost use it daily and plan my day
| accordingly.
| [deleted]
| KerrickStaley wrote:
| I built something similar recently, linking it here in case
| people want similar projects for inspiration:
| https://www.kerrickstaley.com/2022/02/25/transit-panel
|
| I think the biggest difference is that I wrote my version as a
| web app without any backend (it gets data from a REST API + a
| hardcoded schedule as a fallback), so that I could host it on
| GitHub pages and display it on a cheap Android tablet. I still
| use it every day and am glad that I made it :)
| habibur wrote:
| > Since I already had an unopened Raspberry Pi 3B that I ordered
| in 2016 (6 years ago!!)
|
| The key line. RPi aren't any more available as like before, for
| your new projects.
| ajsnigrutin wrote:
| Yep.. I'd have used an esp8266 for this, and kept the rpi in
| the box, for when I "really need it".
|
| And it truly is a sad time for rpi-based projects... it really
| plugs a gap between cheap microcontrollers and power-hungry
| servers/PCs,...
| Mumps wrote:
| I wonder if a Pi Pico W would be sufficient to run this,
| even? waaay cheaper (and available).
| ajsnigrutin wrote:
| I just took a quick glance at the specs, and sure...
| running an lcd and parsing some text from the web seems
| totally doable, and in contrast to RPi (3, 4...), you can
| actually buy picos :)
| will0 wrote:
| Looks like it's been hugged to death. Archive.org link:
|
| https://web.archive.org/web/20221102223146/https://purplehoi...
| fersarr wrote:
| Wow! I wasn't expecting this at all. Thanks for the cozy hug of
| death :) Also, thanks for posting the archive link! I'll try to
| make it more resilient for the future.
| wirthjason wrote:
| Now if someone can build something to track ghost trains. I'm
| looking at you CTA!
| parkersweb wrote:
| If you're interested in this you might also be interested in a
| project I'm currently involved with.
|
| There's a legal obligation in the UK for bus operators to supply
| live vehicle location positions and static timetable data to the
| Bus Open Data Service here : https://data.bus-data.dft.gov.uk
| fersarr wrote:
| Oh that's great to know! There seems to be an experimental API
| already, will have a look :) thanks!
| scary-size wrote:
| Awesome! Did something similar using GTFS data. Used an e-ink
| display though: https://github.com/Scarysize/transit-pi
| gala8y wrote:
| E-ink is much better choice.
|
| Bus & Mag-Lev?
| scary-size wrote:
| Bus and ferry in Hamburg
| gala8y wrote:
| Cool.
| ranger_danger wrote:
| Now if only this could be done for public school buses that never
| show up at the same time. Younger kids are required to be dropped
| off/picked up in the presence of an adult, but one is often left
| out in the cold/snow/heat/whatever for far too long wondering if
| the bus will ever arrive, or if they were already passed by.
| reckless wrote:
| I'd definitely recommend you use homeassistant as a front-end for
| this. You can then update a 'sensor' using an mqtt message.
| chandlerswift wrote:
| I'd been exploring a similar project a few years ago, and ended
| up making a map that showed the location of buses along the
| routes I tended to take. I was pretty happy with it...except for
| the fact that it was built for the town (Duluth, MN) I went to
| school in, and I didn't get it finished until finals week of my
| last semester, and I left town immediately after!
|
| https://chandlerswift.com/projects/bus-tracker
| bitxbitxbitcoin wrote:
| That board deserves to be on display at City Hall or something.
| Inspiring work and I lament with you that you weren't able to
| use it more than a few days.
| chandlerswift wrote:
| Thanks! :) I definitely thought about seeing if I made a
| polished version, if I'd be able to sell a copy to the local
| transit authority, or something. But it made for a great
| conversation piece, and was tons of fun to build, so it's
| definitely a success as far as I'm concerned.
| colanderman wrote:
| I did a similar thing as a web page an eInk tablet. What doubled
| the value for me though was adding a weather widget to the
| corner. It shows me:
|
| * the current temperature
|
| * the high _or_ low over the next 12 hours
|
| * graphical forecast of the 12 hours (including chance of
| precipitation)
|
| which is all the info I need to know to dress for wherever I'm
| taking the bus to. You can get all this info (including
| graphics!) from weather.gov DWML, e.g.
| https://forecast.weather.gov/MapClick.php?lat=40.7143&lon=-7...
| gedy wrote:
| I know buses rotate and really not practical, but I'd try putting
| an Apple AirTag somewhere on the bus discretely and track that
| way.
| omh wrote:
| I love the form factor of this and the ambient data.
|
| TFL do have some quite good APIs so you could use those rather
| than scraping the HTML.
|
| https://tfl.gov.uk/info-for/open-data-users/api-documentatio...
|
| I think you need to register but they seem happy to have amateurs
| and enthusiasts using them and they work quite well.
| fersarr wrote:
| Thanks for the feedback on the form :) And yea, using an API
| would be much better! I wasn't aware of it, thanks!
| et-al wrote:
| For anyone who's looking to build something similarly, you want
| to search for your agency's GTFS Realtime feed:
| https://gtfs.org/resources/gtfs-realtime/
|
| Transitland offers an API that's easier to use than parsing the
| agency's XML imho: https://www.transit.land/
|
| None of this will still solve the issue of ghost busses, though.
| ;)
| throwoutway wrote:
| Anyone know what that screen is? I don't see a link in the
| article
| fersarr wrote:
| Oh Sorry! I should have added that. Here's a link to it
| https://thepihut.com/products/hdmi-4-800x480-ips-touch-scree...
| fersarr wrote:
| Finally started using my Raspberry Pi! I built a bus clock to
| know when to leave the house and never miss the bus again. Wrote
| this little post to share the details and some pictures.
| pmontra wrote:
| "Error establishing a database connection"
|
| Probably HN killed the server.
|
| BTW, where did you buy the Pi, or did you already have it at
| home?
| noodlesUK wrote:
| It's sad because I desperately want a raspberry pi or two for
| some projects I've been kicking the can on, but I simply
| can't get them for anywhere close to MSRP. The shortage
| hurts.
| Grimburger wrote:
| Perhaps try an equivalent like odroid? You usually get far
| more compute per $ anyway.
| icelancer wrote:
| We switched to Odroid XU-4s for this reason.
| dual_dingo wrote:
| I haven't closely monitored the situation for years now,
| but it used to be the case that OS/software support for
| anything than a Raspi was often spotty at best.
|
| With a Raspi, you not only have Raspian/RPiOS that fully
| supports all models back to the first one from 2011, but
| a decent number of really good alternatives like Fedora,
| Ubuntu and special appliance variants, e.g. for console
| emulation etc.
|
| In contrast, my last experiments with some other SBCs
| consisted of downloading some ancient ISO files of
| questionable provenance from some shady .cn domains. It
| might have gotten better, but one should carefully
| investigate the software situation before buying a non-
| RPi SBC.
| icelancer wrote:
| This is getting significantly better and fast - largely
| due to RPis being unavailable for 2 years and growing
| (and won't get better anytime soon). Odroid's ecosystem
| is quite a bit better these days. I highly recommend
| getting an XU-4 from Ameridroid or HardKernel themselves
| (my last order arrived within 10 days from South Korea to
| the west coast with zero customers issues) for a fraction
| of the RPi 4 MSRP cost (much less what it actually costs
| now) and tinker.
| fragmede wrote:
| It depends on your level of expertise and how comfortable
| you are straying from an online guide. It's just a small
| matter of computer engineering, for different difficulty
| values of "just".
| JonathanBuchh wrote:
| https://rpilocator.com is great for finding Pi's closer to
| MSRP. You just have to waif for them to be in stock.
| [deleted]
| JoshMcguigan wrote:
| Thanks for sharing! In the first screenshot of CLI output, it
| seems to show three buses all being 1 minute out? Am I
| misreading that?
| fersarr wrote:
| Yea I was surprised with that one too. It wasn't my local
| station but I think that sometimes happens when it's a busy
| station at a busy time so they have more than one bus. Or it
| might be a bug.
| handelaar wrote:
| Not very surprising to me that they'd start bunching by
| Bethnal Green tube having all just been slogging their way
| through Mare Street in Hackney, honestly
| ge96 wrote:
| Ha I taped one (with camera) to my window to spot when the FedEx
| truck was coming. (no vision just periodic images uploaded to
| local website).
| fersarr wrote:
| Was this in order receive your personal deliveries?
| ge96 wrote:
| Yeah my apt complex sucks, doesn't accept deliveries and
| FedEx doesn't have tracking like Amazon does. Usually I try
| to change the delivery address to some hold location but
| sometimes not possible.
|
| It was a lazy update every 5 seconds loop/webpage updates
| image url with time query. Not great but did it's job.
| l72 wrote:
| I love these types of projects. Being able to automate or make a
| daily chore easier is so liberating.
|
| As a public transit user, I too have written a dashboard for my
| transit system on top of the smashing dashboard. It runs on a
| raspberry pi hooked up to a TV in my front room.
|
| As others below have complained about arrival estimations being
| unreliable (or these days where we are low on operators and have
| a bunch of ghosts buses!), I found having a map with real time
| location gives me a better idea when I should leave:
|
| https://blog.line72.net/2019/08/02/announcing-realtime-bus-t...
| quijoteuniv wrote:
| For a moment i though he did a solution for the <<ghost buses>> .
| I always used the bus app and it works fine untill, from time to
| time, you turned 2/3 minutes before to the bus stop, timer goes
| down, then says due.... And disappears!!! And no bus pass, trust
| me, i question myself several times. The 254 is a common offender
| of the "ghost buses" :)
| selectodude wrote:
| It's somewhat comforting in a bad way that this isn't an issue
| isolated to my city. We even have the same name for them.
| zeristor wrote:
| 254?
|
| https://tfl.gov.uk/bus/route/254/
|
| I was at a TfL hackathon once, at QMW along this route, but
| that is irrelevant.
|
| Strangely TfL seemed to be beholden to Ordnance Survey for some
| copyright issue, it couldn't have been for the Natrional Grid
| reference could it?
|
| Converting between lat/long to OSgrid was a bit tricky when you
| have to take the curvature of the Earth into account to get
| that last bit of accuracy.
|
| https://www.movable-type.co.uk/scripts/latlong-os-gridref.ht...
|
| PS For some reason I almost wrote Couverture of the Earth, just
| trying to reduce chocolate intake.
| quijoteuniv wrote:
| Mmm... maybe it was the 271 now that i think of it. But it
| happen with others too
| [deleted]
| jpribyl wrote:
| The problem I've faced is that the official live update arrival
| times are often wrong.
|
| I've fantasized for years about engineering a network of self
| contained + solar powered microcontroller / camera units that I
| could place on top of bus stops to track them myself.
|
| Then again, by the time I get around to it the official arrival
| times will likely have become more reliable.
|
| Any rate, great write up- thanks for sharing!
| nsteel wrote:
| In London the TfL API includes access to their live CCTV
| traffic cameras. I think you now have to register but it should
| still be there.
| acomjean wrote:
| It's a fun problem. We hire 4 trolleys for our open studio
| event in Somerville. One of our volunteers bought some smart
| phones, and we pulled a together a php and MySQL back end, some
| google maps and Trolley Tracker. We can see them bunch up over
| the course of a day.
|
| A lot of transportation services have tracking now.
| l72 wrote:
| Arrival time estimates are really difficult. I much prefer
| being able to see where the vehicle is on a map and make my own
| decisions, based upon my own experiences.
|
| However, I played around with one provider (Availtec's)
| estimations for Birmingham, AL's bus system.
|
| This looked at the GPS position of the vehicle to see when they
| actually arrived at a stop and back compared it to the running
| estimation time. As we can see, it isn't great.
|
| https://blog.line72.net/2019/08/06/validating-availtecs-bus-...
| RektBoy wrote:
| Why is the live data wrong? Why is it called live data, then?
| HH
|
| For example, here in Prague, trams always arrives on time
| schedule or few minutes after that. (you can wait 2minutes lol)
|
| Also all of our public transport has publicly accessible GPS
| tracking. Buses are more off of the time schedule, but you can
| check the GPS and compute the live time.
|
| And subway doesn't make sense to track, since it arrives every
| few minutes at any station.
| samstave wrote:
| Ha! me and several engineers from Lockheed built just such a
| thin in 2007 -- but we couldnt get funding for it (we built the
| RFID tracking system for the military) but we were too early
| for the market at the time and people werent educated about
| tracking so we go rejected all over....(it was for fleet
| operations - we built the tracking systems for all weapons
| shipments and containers for the military at the time.
| mikepurvis wrote:
| The Transit App [1] crowdsources position data for vehicles.
| It's a gamified thing that rewards you with points or whatever
| for leaving the app running with your GPS on while in motion.
| This lets them have up-to-the-second knowledge similar to how
| Google Maps running on phones gives Google live traffic data
| around the world.
|
| [1]: https://transitapp.com/
| j0yb0y wrote:
| They also recently released a developer API [1]. The free
| access looks okay for personal use, I haven't tried it yet.
|
| Oh and if your public transit service has GTFS then just
| install home assistant and get maps and arrival times.
|
| [1]: https://transitapp.com/apis
| mikepurvis wrote:
| True, but I think part of the point is that the GTFS data
| is subject to the technical competency of your local
| transit agency, and that seems to vary widely-- sometimes
| they lie about where vehicles are, or pretend that
| schedule-inferred positions are GPS positions, or they're
| missing vehicles, or the data is delayed, or whatever.
|
| When Transit captures this information from their own
| users, it's much more trustable-- basically all they'd have
| to watch for is someone maliciously poisoning the data by
| telling the app they're on a bus when they're really in a
| car, but that would be a lot of effort to go to just to be
| a jerk and end up shadowbanned.
| srmarm wrote:
| In London? They're usually quite accurate - used to be tracked
| by roadside beacons so had less resolution but now it's all GPS
| I think.
|
| Of course sudden traffic, letting an elderly passenger get etc
| will mean that the countdown won't be the same to the second.
| But that's going to be the same if you used roadside cameras
| too.
|
| Generally it should be seen as more of an estimate based on how
| long the last bus took to arrive from the same point rather
| than an exact prediction but it's usually useably accurate in
| my experience.
| fersarr wrote:
| Yea so far they are mostly accurate but there have been one
| or two occasiones with minor delays. I didn't know they used
| to have roadside beacons :| How did those work?
| beckingz wrote:
| Oh this is cool.
|
| It's a shame that the WMATA bus data here in DC is so bad. The
| APIs are fine, but the data is all over the place.
| teeray wrote:
| Small UX idea: what you really care about is not when the next
| bus arrives, it's "can you make it?" Of course, you can arrive at
| the latter from the former, referencing the current time, and
| roughly how long it takes to get to the bus stop (with reasonable
| buffer time).
|
| Or you can do this work in code, and put a countdown timer
| beneath each bus time (such that you walk out the door before
| time expires and you will make it).
| qwertox wrote:
| I have a tablet mounted on the wall which displays different
| kinds of stuff, like weather conditions and forecasts and so
| on.
|
| Among this is the time of civil dawn, because at this time I
| don't want to be riding bike anymore since it's getting dark
| (and colder).
|
| Next to it is a countdown timer with an offset of minus two
| hours, since I do ride my bike around 1 to 1.5 hours. So when I
| see that this timer is reaching 0, I know that I'm at my last
| opportunity to go for a bike ride that day. Once it reaches 0,
| it shows the countdown to the correct, non-offsetted time of
| civil dawn, but in another color, so that I know that I still
| have time to make a shorter ride.
|
| I barely look at the time of dawn, since the countdown timer is
| so much more informative for me. It let's me know how many
| hours or minutes I still have to do things.
| sokoloff wrote:
| > civil dawn
|
| Do you mean civil dusk?
| qwertox wrote:
| Right, sorry and thanks for pointing it out.
| phh wrote:
| My dream UX for that is a single ambient led ranging from green
| to red, but making it overall usable counting we're two, using
| two different trains, with different WFH schedule is rather
| complicated
| Scene_Cast2 wrote:
| Check out CityMapper. It handles your use case, as well as
| multi-transit hops (e.g. bus to subway walking time) as well.
| knodi123 wrote:
| Small world. I did this on behalf of BlirpIt for UVM back in 2009
| or so. We had trackers on each bus, and they would report
| location on a certain interval, or whenever the speed changed by
| a certain threshold from the speed at last report. We had server-
| side geofences on each bus stop, and defined a "route" that was
| just a chain of stops, and then we stored a moving average of
| time between each pair of stops and that was about it. One of the
| more fun projects I was doing back at that time!
| timmaah wrote:
| Small world indeed.
|
| > then we stored a moving average of time between each pair of
| stops and that was about it.
|
| Modest. It got a little more sophisticated once we brought code
| inhouse.
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(page generated 2022-11-04 23:01 UTC)