Show HN: I replaced a $120k bowling center system with $1,600 in ESP32s

Hacker News new | past | comments | ask | show | jobs | submit login Show HN: I replaced a $120k bowling center system with $1,600 in ESP32s 2935 points by section33 14 days ago | hide | past | favorite | 360 comments I might be the only SRE on Earth with his own bowling center. It's a more in-depth gig than you'd think. My family and I bought an abandoned 8-lane bowling center in the rural mid-west. In our small town there weren't many recreation options for families. You've heard of a food desert? This is an R&R desert. It had been abandoned for a good reason. The roof leaks, the electrical system was constantly surging, and my 70-year-old bowling equipment (still) doesn't work perfectly. The system that keeps your score is particularly interesting to me. It's the thing you watch during your game, but it fades into the background beyond that. Turns out these things are really cool, but absurdly expensive. Ours was installed in 2008 and cost six figures. It's calculating ball speed and trajectory, camera-based pin detection (object detection and trig, on ICs!), runs the fouling, the animations, the pinsetting machine and ball return. Very cool stuff for its age. From the business perspective, my facility only cost me $105k. To forklift-replace the score keeping system runs anywhere between $80-$120k, depending on features, vendor, and unit age. No upgrades or service contracts, mind you, and every feature and customization is a new line item. That's for a 1:1 replacement on a system installed in 2008. Incredible, given how fast the tech world moves. Replacement parts cost a shocking $4000 per pair of lanes. But wait, the bowling machines themselves are 70 years old, so what's this "advanced" system actually doing back there? Actuating a single relay to trigger that big old machine. Everything else is strictly mechanical. Meanwhile I've got a six-figure invoice in my hand. I'm upset. Given the state of open hardware, computer vision, real-time event streaming, and open source running megascale products worldwide, there had to be a way to do this myself. So far I've built an equivalent prototype for about $200 per lane-pair, $400 if you're fancy. ESP32 and ESPNow with an RS485 fallback, reporting to a raspberry pi lane computer that's really just redis and a state machine bolted to an ESP32 gateway for the mesh. Since it's all ESP32, I've got a fistful of spare controllers in a drawer, pre-flashed or waiting to be. All common off-the-shelf hardware: microcontrollers wired to relays, optocouplers, and IR-break-beam sensors, each running slightly different firmware. Writing the firmware and protocol is the actual hard part. It's an ESPNow star-topology mesh: each node emits events from its sensors and accepts commands for its controls, reporting to a gateway node connected to the raspi over UART. From there it's event streaming: RX packets get translated and tossed into redis, commands relay back out to the mesh as needed. RS485 sits underneath as a wired fallback for noisy RF environments. Once the data's in redis, it's familiar middleware/React/websocket/pub-sub stuff. Any React dev can build their own UI and bowling animations. Since it all runs on commodity hardware, I can do legit anything I want as the proprietor, and I own all my data. Repairs take five minutes; I can swap the rig on a lane pair in under 10. I'd bet a house like mine could go from zero to running in an hour or two. We're calling it OpenLaneLink, and I plan to open source the hardware, firmware, and software stack when it's ready. Bowling is fun, and I want to help keep it affordable for alleys like mine. I hate vendor lock-in. I'm not a fan of closed systems, calling support for every hiccup, or paying to "white label" my own equipment. Want to go Tron-themed for a night? Good luck finding a neon neumorphic theme in something bought at the turn of the century. All that bugged me. Sure, bowling equipment is niche, but the open hardware and software landscape is amazing. Thanks for reading! Let me know if anyone's interested in more posts about this bowling nonsense. HeyLaughingBoy 13 days ago | next [–] Thank you for posting this, it reaffirms what I've been thinking for so long. There are many opportunities to retrofit old systems of all types with modern low-cost embedded technologies. Around 2019 or so I was approached by an engineer who had a small business retrofitting very old machine tools with modern motion controls. Think very large lathes and planers. The problem they had was that in order to get these systems working with newer controls, they had to make time-consuming modifications to the old machines, in some cases modifying the axis motors and that cost added up quickly. The engineer realized that it was theoretically possible to take the old analog position signals and convert them into something a modern motion controller could read. That converter box would make the retrofit pretty much plug & play, but he didn't have the programming expertise to make it happen. We probably built the first iteration of the converter for under $50 in parts and less than 50 hours of development time. That had me searching for other similar opportunities. I have found a few, but they tend to be one-offs that aren't worth the time unless you're already building something similar. Either that or my ability to see opportunity sucks! reply madaxe_again 13 days ago | parent | next [–] Yup. I live on a river. We flooded catastrophically in 2019, which made me suddenly care about the government’s network of river level meters. Turns out, they abandoned most of them in 2008, as it was the local council who were meant to maintain them, but they couldn’t afford it - a chat with the president revealed they’d been paying €15k a year for each station to maintain it and they’d cost about €100k each. I went and looked at the battered remains. Sounding tube. Ultrasound transducer. Box of 90’s electronics. Anyway, long story short I banged out six of them for them for about €80 a piece - the expensive bits were the batteries and the dinky solar panel. ESP32, ultrasonic transducer, GSM and LoRa (as two are outside of the cell network), haven’t had to touch them in five years and we now know when it’s time to evacuate, rather than wading out in the night while trees sail past us at 60kph. So much stuff like this. reply japhyr 13 days ago | root | parent | next [–] Where are you located? Around 2020 I put together a landslide risk monitoring site that's entirely based on stream gauges: https://khmpsitka.org It's an interesting approach that's way simpler than relying on soil moisture sensors placed high up on mountainsides. It's not as widely applicable as measuring soil moisture directly, but it's been running steadily for over 5 years now. reply fragmede 13 days ago | root | parent | prev | next [–] They didn't offer any of the €15k a year to you, did they? reply madaxe_again 13 days ago | root | parent | next [–] They hadn’t been paying since 2008, hence it was all derelict trash - they don’t even have the budget to maintain the roads or keep the school open, never mind monitor river levels. My interest was not drowning, rather than pecuniary. reply cechmaster 13 days ago | root | parent | next [–] so what are they doing? reply madaxe_again 12 days ago | root | parent | next [–] Care and education, and whatever they can manage with whatever’s left over. Same as pretty much every council everywhere. reply smm11 12 days ago | root | parent | prev | next [–] Next you can hook up an abandoned nuke silo, right? reply madaxe_again 12 days ago | root | parent | next [–] Pretty sure you could manage launch control with nothing but a bunch of ESP32s and home assistant. Sadly there are no rad hardened ESP32s I know of, but that’s what the silo’s for. reply ryukoposting 13 days ago | parent | prev | next [–] I think I see some parallels with the aftermarket for old cars. Holley's entire catalog is "here's a thing that'll modernize your 1960s engine without replacing the whole damn engine" This kind of thing is a low-volume, low-margin business by nature. It's those kinds of businesses that the megalomaniacs of our field tend to ignore. There are people with needs, and money they are willing to exchange for a solution to those needs. But there's no path to world domination by selling carburetors (or bowling alley control systems) so those problems never get solved by anyone with the means to do so. It's a shame, really. reply red369 13 days ago | root | parent | next [–] I once expected an aftermarket industry to pop-up to hybridize old cars. Old rear-wheel drive manual cars sound easiest. Generator attached to the flywheel instead of the starter motor, and then find some way to squeeze a drive motor by the rear diff (probably more complicated, but surely not impossible). I thought something might pop up once companies like Bosch started making generic e-axles for manufacturers to use. With a small Li-ion battery (and all the usual inverters, etc.), it could work like a manually operated version of the dual-motor Honda hybrid system. Put it into neutral, and whatever energy is in the battery could drive the motor on the rear axle. The engine could automatically kick-in and drive the generator if there's not enough in the battery. It would never be as economical as a purpose-built hybrid, but old manual cars are often reasonably economical on the open road, and terrible in city traffic. Targeting only the urban fuel consumption would go a long way towards keeping them useable, with the added bonus of making manual shifting optional in stop-go traffic. Small motors would be enough for city speeds, and with a small battery, it sounds cheap to me at least. I doubt it could ever be a simple kit, but I thought people would have a go. reply studog 13 days ago | root | parent | next [–] People probably are having a go. Here's one for pickups: https://edisonmotors.ca/trucks/pickup-conversion/ reply Scoundreller 12 days ago | root | parent | prev | next [–] > Generator attached to the flywheel instead of the starter motor, and then find some way to squeeze a drive motor by the rear diff (probably more complicated, but surely not impossible). Some vehicles have this as a “battery starter generator” where the “hybrid” functionality is entirely on the accessory belt. https://www.bosch.com/stories/48v-hybrid-battery/ https://hackaday.com/2025/01/24/bosch-starter-motor-freed-fr... reply humanpotato 12 days ago | root | parent | prev | next [–] Automotive engineer here. One consideration for the diff motor is that it would REALLY sag the diff. I think the only way to go would be a front and rear generator/motor combo in one housing to replace the transmission, powering the rear end with a driveshaft. A direct drive clutch between the front and rear motor/generator would economize driving and assure high power at high speeds. reply BizarroLand 12 days ago | root | parent | next [–] How about a front wheel mounted drivetrain with the motors built into the wheel hubs? That would effectively add 4wd to old cars and allow the onboard engine to work normally with an option for eboost/edrive with the only extreme modification being adding the battery and control modules. reply high_priest 12 days ago | root | parent | next [–] You would have to provide custom replacement hubs, for all the vehicle types you want to support. Plus, adding a clutch system to a hub drive is not feasable. So, the hub engines are engaged all the time. I've considered it as a modification for FWD track performance cars. It is much easier to add a hub into a stiff rear axle. Turns out, that adding an electric motor, which is not part of the main engine assembly, ads way too much complexity in controlling the whole thing and weight to power ratio, that it stops quickly stops making sense. reply dajt 12 days ago | root | parent | prev | next [–] We had a guy give a talk at our local nerd meet-up about doing this to an old landrover with the hopes of commercialising it. Did a good job, but it was only for someone with money to burn. Looks like he did commercialise it: https://www.jauntmotors.com/series I recognise some of the photos from back then. reply red369 5 days ago | root | parent | next [–] I'm a bit slow on looking at this, but looks to me like it is for a full-electric conversion and not to a hybrid? Still very cool to see and I hope it goes well for him. The more options the better. reply rzerowan 13 days ago | root | parent | prev | next [–] Wouldnt the weight of the old chassis be a impedement to mods , older models tended to be more robustly buildt. Or what cut-off date for mods would be appropriate (last 10 years?) as beyond a certain cutoff would not be cost effective and most likely would be a hobby project done for the love of it. reply Scoundreller 12 days ago | root | parent | prev | next [–] I was thinking of a “feature” on manuals that ran electrical and accessory-belt stuff full blast during engine braking. The best time to run your a/c or turn the seat warmers: when you’re trying to expel energy. Would give you some extra braking without heating up the engine and take a small load off your brakes. That or turn any vehicle into a mild plug-in hybrid for all electrical loads and flywheel the alternator until that time. Gasoline-powered generators are not very efficient. Might get a few percent extra efficiency without having to touch anything mechanical. reply foxyv 11 days ago | root | parent | prev | next [–] The problem is that environmental regulations kind of act like a double edge sword with regards to hybrid conversions. They prevent Jim Bob from selling his environmental disaster kit, but they also prevent Bob Jim from selling his Hybrid drivetrain conversion without expensive approvals. This is why most people do BEV conversions. The kits are available because they are zero emissions and don't fall afoul of the environmental regulations. reply kfse 13 days ago | root | parent | prev | next [–] My guess: 1) New cars are too cheap to make at scale. 2) Old cars are quite unsafe to drive, comparatively (airbags, backup cameras, lane departure alerts, blind angle alerts, etc) reply jimnotgym 13 days ago | root | parent | next [–] 2) cars have had airbags for a pretty long time. Backup cameras are a simple retrofit. Lane departure alerts are not universally loved, mine is turned off... reply rockostrich 12 days ago | root | parent | next [–] To be fair to the person you're responding to, airbag systems in modern vehicles are a lot safer than the single airbag per front passenger in older cars. The original airbag systems were just a single bag that deployed at a single rate based on an inertia sensor. Modern systems have several bags with multi-stage deployments that are inflated depending on seat belt and weight sensors. But yea, as for the rest of the "safety mechanisms" the only modern change that I can think of that's not easy to retrofit but is a huge safety boost is blind spot detection. As someone that drives older (and smaller) cars, being able to see the blind spot detection light on other cars' mirrors is always a bit of a relief that their car will notify them if they try to change lanes. reply noir_lord 13 days ago | root | parent | prev | next [–] Aerodynamics as well, new cars and especially ev/hybrids are slippery compared to many/the average if we take old cars to mean 50’s through 70’s. reply jimnotgym 13 days ago | root | parent | next [–] Does that matter much if you only drive around town at 30mph? reply rob74 13 days ago | root | parent | prev | next [–] An older sedan-style car might still be more aerodynamic than a modern SUV, simply because the frontal surface area is smaller. The less air you have to push out of the way in the first place, the better. reply cansofgrease 12 days ago | root | parent | prev | next [–] The big one is probably cost and scaling. reply psd1 12 days ago | root | parent | prev | next [–] Cameras are a mitigation for high waistlines, and only a partial one. Keep your cameras and alerts, and give me a car with better fields of vision. I think there are important dimensions of safety that go unmeasured. You have much less road awareness in new cars. Survivability is great and all, but not at the expense of children and pets becoming invisible. All the focus on survivability provided another incentive for makers to put ever larger pieces of steel on the road. I disagree that new cars are safer. I have experienced driver aids glitching, and i want none of it. Anything that can take control of the car needs to be bulletproof, and it isn't. reply yobbo 13 days ago | root | parent | prev | next [–] Stuff like this exists for bicycles. For mopeds and motorcycles there are electrification kits. It should be possible to just replace the flywheel altogether with a generator/motor that both brakes and powers during each cycle, cancelling vibrations. Then more generation during deceleration, and more power during acceleration. reply mattgrice 12 days ago | root | parent | prev | next [–] In the US RWD manual cars have been exclusively sport/GT for decades. They aren't cheap and a hybrid swap and/or daily driving miles would destroy their value. reply high_priest 12 days ago | root | parent | next [–] There are hybrid packages, which are very good for performance applications. A performance oriented conversion, done well, should boost the value. reply ozim 13 days ago | root | parent | prev | next [–] There is no shame and no business there. We just read a story of someone who didn’t want to pay market price and went DIY. There are companies doing bowling alley equipment and you can pay them for maintenance. Is there a single one of those on F500 list? No and people are running those companies and what OP did … he didn’t want to pay market price. Well yeah those companies are overpriced if you are software engineer who can wire up and program couple of ESPs have own bowling alley and have free time. reply mrb 13 days ago | root | parent | next [–] Don't dismiss the OP so abruptly. IMHO he is convincingly making the case that there is likely a business opportunity for something between a $120k off-the-shelf system and $1.6k in DIY hardware. reply tonyedgecombe 13 days ago | root | parent | prev | next [–] It's just lack of competitive pressure. I bet if you investigate you will find there are only a couple of suppliers that have the bowling alley market sewn up between them. reply nativeit 13 days ago | root | parent | next [–] You’d die on the back of unreliable operation and relatively high maintenance. A DIY system built off of cheap ESP32s is never going to be reliable enough. The system as described above is the sort of thing I would happily operate for myself, but would never attempt to sell as a product. Anyone who’s tried to hold together a few dozen ESP32-powered IoT devices will likely attest—they’re very impressive for their cost, but hardly reliable on the scale of years. reply Scoundreller 12 days ago | root | parent | next [–] > but hardly reliable on the scale of years. I’ve had similar experiences with “enterprise”-grade hardware. But sometimes the “price” isn’t just the hardware, but also having someone on-call 24/7 to support and possibly fly-out to investigate within X hours. reply section33 12 days ago | root | parent | prev | next [–] Oh totally. I actually thought about exactly that. I'm basically thinking "this -will- fail at some point, so when it does, I want to be able to replace a failed unit very rapidly." I'm tinkering with an auto-provisioning function that tells a given ESP what node type it's connected to and configures itself from there. reply kfse 13 days ago | root | parent | prev | next [–] Work out how many bowling alleys there are and how many of them are in the market for an upgrade or a fresh install, trying to get to be the ki…