PolyGen - Inside the game - EMF 2026

Hi. So, uh, for those of you who've been around EMF a while, there's been a few generations of this. So, it started with orbs and then went on to, um, to to Polycoin and then Polygen is the the latest version. So, I'll kind of run through some of those as we go. Uh but yeah, Ingress was my inspiration and uh and AMF and then I thought I'd create something. So that was and this is the the series the the orbs game in 2018, then Polycoin uh 2022 and then from 2024 was Polygen. And um there was there was some interesting things, lessons learned as I went along the way. Uh the first one was there's no that that just beeped and had some flashy lights and nobody really knew what was going on with them and it kind of worked but it the basis was there. And then so in Polycoin I made speakers and actually have it speak and make lots of flashy colored lights that were more interesting. And then Polygen was the result of um the cases for Polycoin melting. And [laughter] um so I left them in a tent in um MCH and when I came back the rear one of the empty cases the rear side of most of the cases more resemble Pringles than uh than than that unfortunately. So this is like one of the last surviving ones that's vaguely the right shape. Uh but I learned a lot of lessons in 3D printing to do with this as well. So, uh, but they look I I really like the look of these, but the, uh, things like the speaker on the back didn't work so well, um, because it would be sat up against things and then no one could hear what they were saying. So, the speakers moved to the front in in polygen. And the the overall design didn't use PLA. Lesson learned. And, uh, the new ones are imprinted mostly in polycarbonate and some in PET G. Just experimenting with that. And the main thing as well is that they don't fall apart when you drop them typically, unless the case actually breaks. These ones would the back would fly off, bits would come out everywhere. It wasn't pretty. Um, so, uh, there was a whole bunch of other things. Um, I had introduced a new team as well, so we have four teams instead of three. And the So, the I won't bother explaining the whole game. Hopefully, you've all played the game, so you've got an idea. Uh, but this was some of the interesting stuff I did with the these cases. Um, but that one um these were wonderful for the first time. Once you take them off, they don't go back on again so easily. So, that was a lesson learned for keeping the backs on these. So, the Polygen cases, and I'll go through it and show you the how that works. But the main thing is I used Tinkercad and I got myself a bamboo printer which is how I was able to print polycarbonate and that inspired polygen. It's the same PCB. So I took the PCB out of this cuz I didn't want to iterate that and put it into the into the new case and rewrote some of the software around it. The main parts are that um the PCB sits inside here. There's uh there's the um NeoPixel LED sat at the front and then all the way around the edge is are the NeoPixels speaker sits here behind this and then these catches here they retain the they retain the base of this. So there is a a safety screw that I've removed for speed. Uh but to actually open the case up you you use magnets. So, a magnet there and there. Uh, and it's actually two P coins sat inside there. So, so when you open that up, just unhook that. And you can see that the wonders of two P coins holding it, they are magnetized by that. And they just hook onto these two bits here to keep them in place. And then you got access to the PCB through there. So to to remove the to remove this, the easiest way is to remove the catches entirely from from the case. And then this this piece will just rather difficultly slide off. So you can then see inside. So you've got the the three cells. They're all in parallel. So it's a sort of 3.7 volt. You've got an MP3 player there that is just a DF robot 299. It's got a micro SD card and it plays plays the files through there and then two different NeoPixel runs. And what it does is a lot of the architecture of this is all about power management. I needed to keep the power usage low so they could run for a whole festival without me having to recharge anything, swap batteries out. So what it does is it actually powers down any LED strip. It's not actively driving. So, it it turns the power off to it via a FET. And the I'm not going to pull this out because they're a pain to get back in. Uh, but I'll I'll show you the uh uh the underside of the board. Uh, so kind of talk you through it. You got the a Pig Micro. So, it's a Pig Micro as the brains of the operation. And the reason it's there is because it's very lowowered. It can go into a very low powered sleep mode. and it just doesn't use much power. And it can wake up, turn on the RFID reader, see if there's a card there, then go back to sleep. And it can do the same with the LEDs. It can update the LEDs and then then sleep. And what it does is when it needs to talk to u the game server, it uses this, which is an ESP 8285. Now, everyone goes 8266. No, 8.285. It's like the a tiny version of the uh 8266. And it's just it's smaller. It's more reliable because it's all on DI EROM. And then at the very bottom, you got the power. So that's the power regulator taking it from the whatever the cells are giving out to 3.3 volts. And obviously the RFID reader, which is a terrible knockoff thing from sort of online from somewhere. And that's that's essentially all the components there. And to to to program it up, uh you got a whole load of pads there. So I I just put this pogo pin. So it's got pogo pins on one side and I can just hold that on there and program up the different components of the board using that. So it's a it's a nice way to just not have to solder extra connectors on and and worry about them. The uh these this is always the challenge when you're making something like this. You're being pulled in so many different directions. You want to make it secure. you've only got a limited amount of time and you got a limited budget and you need the power to work as well. So all those things it's a compromise. So a lot of this stuff is is all about power, all about keeping the component cost down so I could afford to do make 36 of them as I did. So um yeah, there definitely some challenges with that. Uh I talked you through this already, so I'll skip that. Did it in Kyad. Uh the the schematics are online if you want to have a look and it's running microython on the ESP and it's running I think something called pig pig micro uh pig basic on on the pig micro and but I hit the hardware quite hard. So a lot of what the pig micro does is interrupt driven. So if you've done microcontroller development, it effectively it can do lots of things simultaneously because it only needs to do go and do it when it gets told something's ready to receive the next bite. So it can actually natively drive the the the pixel strips talk to both modules all simultaneously and it doesn't need to to be particularly highowered. However, I did hit one problem which is at the end of last camp I ran out of ROM space in the Pig Micro. I literally had no more space because these were the pig micros were at the height of the component shortage. So I just had to get whatever I could lay my hands on and I I ran out of space. So actually the what's changed is that it's entirely different pig micro different architecture and I had to rewrite a load of stuff to make it work but couldn't add any features yet. But it's now got loads of ROM space. So next time I've got the opportunity to add something. I showed you that one. And obviously, you know, we we've got the hidden features, uh, which hopefully some of you saw, which, uh, you know, uh, the EMF cam bonus, if you, uh, player, if you came back from last time, you'd have got a bonus. Uh, the, um, there's a command mode, which this will boot up. I'll talk about other things. Um, if you used a payment card, you probably got something along the lines of author um, Visa debit card accepted, authorizing donation to Palibius Biotech. Please wait. Just kidding. Um, so a number of those and I will report how many people used the payment card uh, of some sort or other uh during the the event. Uh, the capture the flag you can ignore. This is the wrong presentation for that. It wasn't active this year. And hopefully you saw the scoreboard that was up in null sector. Uh now I haven't really gone too much into sort of how things communicate. Oh, there we go. >> I can do this now. This is the command mode. So assuming this >> command mode. >> There we go. So this is how I program it up. >> Battery voltage. >> And so I can go through >> power off. So I that's how I turn it off is is is that using the the control token and the way I load config in is actually save it onto uh an RFID card so I can program it with new Wi-Fi details. So, if I need to change so what server it's talking to, what the what the Wi-Fi SSID is, then I can just upload it into there and it will save it and uh I don't have to open the case up to reprogram it, which was a big problem with the orbs game because I had to do that a lot. Um, so yeah, the um the way this uh all communicates is over MQTT. So the there's a Raspberry Pi that's running a Mosquito and has a Python client to the Mosquito broker and then these all sub sort of send messages back to the game server via MQTT and it responds with messages. The messages are all signed. So there's a shared there secrets known by both parties that the that's unique to each device. So the game server knows how what how to how to it's not encrypted. the message is a clear text, but what it does is it it calculates a hash with some hidden with some stuff that is not in the message that it knows to add back in. So that way it the messages effectively are authenticated to a degree and if somebody starts sticking stuff into the MQTT broker that it shouldn't, then uh I'll get lots of alerts that somebody's uh playing funny playing games with it. Um but yeah, most of it is is simple MQTT. This scoreboard is written using Pygame and it uses uh again MQTT. If you connect to MQTT.gen.polybe.io, you will get the scoreboard feed. So anything displayed on here, you you'll have full visibility of and actually you can see a little bit more like um if you're trying to find some of the units and you you can see all of the names of all the units on there um where they might not appear anywhere else. So those uh yeah, if you want to It's quite interesting. Some people have hooked onto the MQTT feed and made the lights of their villages change to the color of the Polygen unit in their village. >> So, um, and there's there's been some excellent like little hacks I've seen. There was somebody created an entire web page that monitored it and so he could see exactly which units had changed teams. He could go take them. Actually, he didn't he didn't go it. He sent his girlfriend to go take them. um the the games uh website where you can set your player name. So this um this is using a thing called metabase to to draw the um the teams uh scores and your individual things. This is all JavaScript and it talks over websockets on MQTT to uh communicate setting your player name and uh you'll have hopefully you've seen what random name the game assigned to you. It's going to be some either obscure or not so obscure sci-fi character name and they appear in square brackets if they're defaulted. So these are all of the different things used in in making this game. And um the the a couple of bits broke this time unfortunately because uh my game server lost its storage. um it would boot up and then say I haven't got a disc anymore and then not re then would not reboot. So I had to rebuild it which meant that my pushover notification stopped working. But everything else is pretty much there exactly as I described. Uh oh yeah, one of the hacks. So this was at Fried Camp and uh this 12-year-old kid, he went around the camp and he got himself an Arduino, got himself a servo and some batteries and programmed it up. So every 30 seconds he would just drop his card down in front of the reader. [laughter] Love that. That was brilliant. Um so um that's the core of of it. But then I'm I'm kind of assuming that people might have some questions uh and want to actually have a look in these units and and see some of them. So I I kind of I'll say let's do a couple of questions and then I'll maybe I could just pass this around to people and you can have a look that this way so you can all be able to Cool. So, yeah. Anybody got any questions? >> You mentioned signing then, but do you have any issues with terminals? >> No, because they have to be registered at both sides. So, if it started receiving messages from a unit, it doesn't recognize it will it won't respond to it. So, yeah, it's >> shouldn't be a problem. Yeah. So, um I don't think I've got a link on the presentation, but if you go to uh PE here we go. Go to that website. It's on the back of every unit. Then there there there's all the sort of very rough notes and a link to the GitHub that's got a lot of the stuff on it. Uh a lot of that stuff needs updating a little bit because of the new pig micro and so on. So I've got to update it with that source code. But >> is there anything you would change? >> Yeah, I mean my case design was not based on was based on need rather than anything else. So I had to I would I I was because I didn't want to change the PCB. I designed the case around the side of the PCB that I'd made which has issues. So, I I've kind of got to um rethink some of that. So, if I do another version, then I'd be designing both with both in mind. And and uh some of the things I've done there, like I' I've deliberately um tried to make it as rainproof as possible. It's not perfect, but it's pretty good. Uh you you may notice there's a drainage hole at the bottom. So, and the speakers waterproof. and the uh yeah I got yeah I I and there's little things like when I designed the PCB I didn't present out all of the IO pins that I could have done and I kind of regret not just having an empty header of IO pins so I could have added something extra um things like that. So there's little bits that I would do, but mostly it's all about redesigning the whole thing as more of a cohesive single product instead of one where I've had to. But part of the the reason for the exact size is because they fit perfectly into a really useful box. >> So what happens when they lose Wi-Fi? Does that happen often right now? >> Right now quite a long time. Yeah. Um, so if they what happens is they check in about every every 3 minutes roughly. Um, and if the game server doesn't see them for about sort of 10 15 minutes, then it boots the unit off. So it basically clears who owns it and says you no longer own this unit. So what you'll see is when the Wi-Fi goes down and then comes back up, uh, if it's been long enough, then all the units will turn white because when they next check in, they go, I'm not owned by anyone. So they they'll flick to white because the game servers decided they're they're not participating. >> No, it's all done online. So they have to have line of sight of the of the game server. So it sends a message to the game server via MQTT and the game server will look up and tell it this this like this this player card you just gave me is on this team and it will then go, okay, I've now been captured by this. And >> cool. Wi-Fi is back. Hey. >> Okay. >> So, that's the orbs game. That was the very first version of this. And uh that one would have had an RFID reader, but all the ones take all the ones from there are now in the Polygen units because they still worked. So, >> what have you learned about game players? What have you >> about the players? >> Yeah. So, I imagine you've seen quite a few rounds of >> I mean there there's been some brilliant stuff over over the years I've run this. So, I think the you you sometimes see people who set their alarm clocks for funny times to get up and then do a circuit and then go back to bed for a few hours and then do another circuit. Um I've we've had sticker campaigns. So one particular team started um uh like leaving like nasty stickers about the other team like they um the this other team farts a lot and things like that. So we had some some some friendly rivalry that was quite amusing. Uh and and uh yeah there was at one particular event two kids actually had a fight over it. Um which didn't go well for the kid who started the fight because the other kid was friends with one of the security guards. So he just did the circuit all night keeping it. [laughter] So his team won. So it's kind of interesting the interactions you get and uh there's sometimes you see players and all they seem to do is is be moving between units and it's not always the most efficient way of winning the game. Sometimes it is, but it's Yeah. >> Is there like a theoretical ceiling for the number of devices or players? I've I mean the number of players kind of is a factor of the um you need enough units to make it playable as you bring more players in. So the reason why I ended up with 36 units is because I was going to a bigger event with more players. So I I needed to upscale. Um and then I don't think there's a massive limitation because they're not they're not heavy duty. there you if you think about it they're only when somebody taps their card is it talking to the game server so the workload on the game server is fairly light uh it's more down to um sort of running the other systems like the scoreboard and generating all of that so I actually put that on different Raspberry Pi so the main one's a Raspberry Pi that runs just the game and then a separate Raspberry Pi just to run the scoreboard to kind of keep it as uh separate as possible I found it interesting with the stage and stuff and like the branding on these books. How how were you involved? Oh, so uh the the Palibius biotech branding that was something invented uh by the Null Sector team and when I I'd done orbs that was it located in Null Sector and then they uh they when we're coming back in 2022 they were like well we're doing this null sector Palibius Biotech theme do you want to be part of it and I was like yeah I can do that so that's how we ended up with the the branding kind of brought in and they they quite like the idea of of taking null sector and bringing it across the whole site. So there's not a huge amount of tie up, just the branding is there to kind of keep it keep it all linked. >> Yeah. So um keep in mind 2022 Laura modules were what 15 20 quid each which when you multiply that by 30 something the cost grows. So like you had a one pound part then now multiply that by 36. It it's it's not viable. Um so I had to keep my my unit cost down. So Laura was definitely not on the table costwise when I first looked at this. Um now they're down to what £3 pound50 or something I think. So it's now getting in the realms of financially viable. Then now the challenge would be how do you do it with the power management? Because if you stick a 60 milliamp constant draw for running the Laura module in receive mode the whole time, you now got a a power challenge. So, um it's something I'm thinking about. I'd love to do how I can make it function as part of the game within the constraints of Laura, not basically completely blitzing the bandwidth available in Laura. Um I've I've got to figure those things out. So yeah, >> how long would the battery last for? >> Depends on the number of captures. So the number of interactions, so uh when I did, uh the busiest event I did uh was uh 39 C3 and one unit ran out of battery during that whole event and that was the unit that everybody registered at pretty much because it was right by where the tokens were. So that the registration process is the absolute killer when it comes to the battery life because all the lights are flashing and it's talking the whole time and even that with those three batteries I just had to do one change and that was after I think 2 or 3 days everything else lasted the whole event. So yeah they can easily run for 4 days in typical use. >> You get a notification if the battery fails as opposed to if they just drop off the network. >> Yeah. So if they drop off the network, the notification is I haven't seen this unit for a while. But they all report in battery status as part of their check-in. And what they will do is uh when it drops below a certain threshold, I get battery is low. And then if it drops below the next threshold, I'll get I'm turning myself off. My battery is now too low. So that uh it does thresholds. And I publish, if you go on the website, you can see the the voltage history for all the previous events uh across the the battery cells. So you can see what they've been doing. >> Yeah. >> Yeah. So the units themselves have no concept of what volume they should be at other than when they check in, they get a config from the game server. So every time they're polling in to say, I'm I'm here. This is my voltage. They'll be told, "Right, you're now volume such and such." Even if it's the same volume, it it just tells it every time. And so when it looks on the schedule and goes, "Oh, it's after 11:00 p.m. We're going to lower your volume." And I can dial individual units up and down as well. They've all got their own unique config. So I can make one unit much quieter. >> Yeah. >> Yeah. You can you can dial it up and down and make it really flexible. Um, and I've only had one request to dial down so far. So >> what was the URL for? Um, so the the map there's not a map online. There's a screen in the null sector that you can see that that on. Although the map is not up at the moment is the screen's up. The scoreboard's up, but the map isn't. Um, I spent my time rebuilding the server rather than doing the map. So, [snorts] uh, yeah. Anybody else? Um, right. >> No, that is still missing. And there is a dead database entry number nine rest in peace. I can see it last check-in date was 2024. >> So that connected to a network would contact your game server. Can it come across? >> Yeah. Could could while the event's running. I mean when is the event's not running the game server is not online. So >> would have to have to set up network for it to connect. >> Yes. Yeah. Have to set up and then >> yeah, emf2024- open I think is the SSI. So, >> um it's MQTT.gen.polybe.io. >> Um, cool. Uh, now you you will probably all want the unique capture if the system's up and running. Um, there we I should have put that up a while ago. >> Got all my all my details. So, what we'll do, we'll get that online and then you can all uh all capture it and get your unique capture that only people here can get. Assuming that's it for everyone. Questions? Cool. Amazing.