101–110 of 118 posts
This is lacking some very critical safety systems such as breakbeam detection (someone walks into the path of a closing door), endstops (the system unexpectedly travels to the end of the track), torque/motor stall monitoring (aka crushing someone to death), and door speed monitor (the door starts moving faster than the motors are moving it)
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I can't speak to the quality of this yet, but I just bought https://www.amazon.com/gp/product/B016D5L5KE/ref=ppx_yo_dt_b... kit to dork around with myself. It comes with an IR transmitter and a whole host of other stuff to play with. That said, I do love adafruit and sparkfun for most purchases. My bank account doesn't, but I certainly do.
Oh, nice! I hadn't thought to look for multi-part kits like that but the next time I am looking for a sensor or emitter or whatever, I might check some of these kits if only because "more stuff!!" I am the same with Adafruit et al. Their stuff is tested, easier to exchange/return if broken, often ship quickly since it's domestic to the US, etc. But when I need a bunch of something I tend to order more direct/bulk. My…
Everything I've been doing is stepper motor related, and I didn't know what else I'd even use 3/4 of those sensors on, but for 25$ or whatever I figured I could buy them, try them, and see what comes out of it. They're like a flight of microbrews or something; just enough to tease me and get me started so I know what I actually want :D
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> No, you will not accidentally meet real-world safety standards with your project by dint of your sterling virtue, high intelligence, wisdom in the ways of the world, and impeccable engineering skills. Nor will you do so by adding a couple more features. Safety is the result of deliberate processes. This is unnecessary condescending snark that I hope we see less of on HN. Everyone should be open to criticism, but ho…
There is no invention here, and nothing to encourage. Electrically operated doors date from the 19th century, and we have over 100 years of understanding of their hazards.
Absolutely there is. You and I both agree we should encourage them to learn properly, experiment responsibly and proceed with safety in mind.
> There is no invention
I regret that you ever saw the word "inventor" and couldn't think past it. {Creator, engineer, maker, hacker, killer} Pick whatever word it takes for you to ignore the noun and focus on the idea and better way forward.
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Not sure this actually happens. In practice. A friend works at an oil company, and they have dozens of rpis deployed on offshore rigs, and in land rigs in the middle east. They are working in pretty harsh conditions, with high salinity, sand in the air, high vibrations, very low temps, very high temps... and yet over the 6 years they have been running, not 1 has had a fault. All use SD cards, and they haven't been gl…
Not my experience with commodity SD card, power supply and stock settings of Raspbian. They must be using some "secret sauce" to make them run 6 years without outages. I would suspect some industrial grade SD card (SLC or at least AMLC), high quality power supply (e.g. UPS with surge protection) and also some way to limit writes on the SD-card.
1. Buy high quality SD cards
2. Remove as much disk-IO as possible, using an external USB stick for raw data storage, logs, swap, etc
3. If you really need to make it stable, make the OS read-only
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You can't use GPIO pins to short 2 contacts together. The best you can do is apply voltage to the contacts (which might be workable, depending on how the remote is designed). To short the contacts you need either a relay or a transistor.
Ah yes, of course. Perhaps a transistor could work as well for low voltage?
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You can't use GPIO pins to short 2 contacts together. The best you can do is apply voltage to the contacts (which might be workable, depending on how the remote is designed). To short the contacts you need either a relay or a transistor.
Ah yes, of course. Perhaps a transistor could work as well for low voltage?
Also I used this remote control only because one of the switches was broken, I didn't have a spare one so I couldn't afford breaking it.
An optocoupler would be better but I figured maybe one day I will repurpose the relay shields for something else, or unsolder the relays. Actually my next project involves both optocouplers (for efficient 12V->3.3V conversion) and relays to drive AC but I will probably have a PCB manufactured for that one!
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.. all data stored on SD card and lost during one of power outages / if someone bumps the cable / if it gets too hot in the summer
Not sure this actually happens. In practice. A friend works at an oil company, and they have dozens of rpis deployed on offshore rigs, and in land rigs in the middle east. They are working in pretty harsh conditions, with high salinity, sand in the air, high vibrations, very low temps, very high temps... and yet over the 6 years they have been running, not 1 has had a fault. All use SD cards, and they haven't been gl…
The default rpi os writes to disk all the time, there is even syslog with periodic messages. I bet your oil company uses read-only root, or at least a customized os which does not log things unless it has to.
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Those are a bit overkill, I've not had any garage door that beeped for opening for remotes for example and that's a similar distance of triggered by someone not in the immediate area. They should be safe based just on the break sensors and current limiting.
Those are the industry requirements written by people with understanding of the hazards of running a garage door opener out of line-of-sight of the door. Read them carefully. There are reasons for each of them. Think hard about it. Remotes also operate differently than your wall button. Did you know that?
The project above is an open source prototype and by no means a product that consumers are expected to buy/use as is.
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>I think it's the worst garage door opener project I've seen on hackernews yet. Would you feel encouraged or inspired if someone said this to you? For example, instead of saying the quote above, you could have as easily said “I think this garage door opener project has a lot of opportunity for improvement”. Mindset goes a long way, and it might just help make a friend or two along the way.
You are correct. I intended to discourage the poster. Any "opportunity for improvement" could be misinterpreted as "just fix this one thing".
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Not sure this actually happens. In practice. A friend works at an oil company, and they have dozens of rpis deployed on offshore rigs, and in land rigs in the middle east. They are working in pretty harsh conditions, with high salinity, sand in the air, high vibrations, very low temps, very high temps... and yet over the 6 years they have been running, not 1 has had a fault. All use SD cards, and they haven't been gl…
The problem ia not vibration or heat, it is power off while data is being written. The default rpi os writes to disk all the time, there is even syslog with periodic messages. I bet your oil company uses read-only root, or at least a customized os which does not log things unless it has to.
I mentioned in another comment though, that the particular workload doesn't result in many writes.