Have you looked at the work done by the OPC Consortium? They are rather far down the track in the direction you are headed. It is a quasi-open source project (membership in the club required ). I believe it was initially funded by Siemens, AB, Honeywell and others. In other words heavy hitters. I believe the initial goal of the project was to replace legacy scada systems, but has traveled far beyond that. After all home/industrial automation is home/industrial automation. The concepts and problems are the same. Why replow fields and reinvent wheels? Arley
On 22/02/16 17:30, Matthias Urlichs wrote: > On 07.02.2016 21:39, Jerry Scharf wrote: >> Here is a problem statement that I wrote up about how to move to what I >> think of as a distributed building automation system. > I'm also thinking about (and designing+coding in) this problem space, > albeit with a few key differences. > > * I disagree that state should only be inherent in messaging. That means > you have nothing to return to after a crash, reboot, or power failure. > "I have no ide whether the alarm system is armed" is not a reasonable > system state. > > * I also disagree that there should be no configuration. Configuration > is necessary. _Something_ shall tell the system what the code for > disarming the alarm is. Or simply which switch(es) control which light(s). > > * However, I agree that any one central essential system must be allowed > to fail, if only to continue operation when updating the thing. The > corollary is that processing may indeed happen anywhere, and should be > able to take over quickly when warranted. > > Talk is cheap. So are concept papers; I have to admit I'm one of the > persons who have discovered that the hard way. You need a minimal > working system to have a reasonable discussion. Haystack has clients and > servers in multiple languages, including some (albeit at first glance > rather rather incomplete) unit tests, but are these actually *used* by > somebody for anything? > > WRT "nest" vs. "thermostat" model: The Nest model is not about > controlling your home. It is about keeping data about your home in the > cloud so that whoever offers the service (Google now owns Nest …) can do > some deep data mining on it. It is also about the complete impossibility > of doing anything whatsoever in your own home as soon as the Internet > connection fails, and of having bricks instead of thermostats if the > company providing their cloud service ever goes belly-up. Or just > decides to no longer support them. > > The "thermostat" model is too limited. Heating is in fact a good > example: If I know the actual valve settings at all my thermostats, I > can raise or lower the central heating's temperature appropriately. This > can save a lot of energy, but might be unstable unless there is two-way > communication between these devices. > > NB: Project Haystack: the first thing I would do with that body of text > (and code) is to rip out their unit system -- including every single > mention of square feet, °F, or time zones. The code to convert between > units MUST be a function of the user interface, not of every single > agent in the system. That way lies madness. > > NB²: "users work with a meta-model" does not make sense. The meta-model > is, per definition, the design of the language which the model is > described in. This is fixed by the system components' design and > implementation. Do you mean that users describe their system at a higher > level of abstraction, i.e. in some kind of macro language? What happens > when the user doesn't provide enough information for the agents to infer > their devices' configuration? > > -- Matthias Urlichs > > > ------------------------------------------------------------------------------ > Site24x7 APM Insight: Get Deep Visibility into Application Performance > APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month > Monitor end-to-end web transactions and take corrective actions now > Troubleshoot faster and improve end-user experience. Signup Now! > http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
