Hi Tom, I'm a mechanical engineer (BSc) with an electrical background (Technical College).
I have thought of and made a small start for non-electrical symbols for Piping & Instrumentation Diagrams, with hydraulics and pneumatical symbols to follow (http://github.com/bert/gschem-symbols/tree/master/piping/). Another use for gschem, netlist and friends could be the simulation of distribution networks of natural gas or tap water, maybe even simulation of drainage systems: ditches, canals and/or large water ways. It's just a matter entering a schematic representation for connectivity (nets), adding the right attributes and invoking a scheme backend with netlist to do your preprocessing and solver stuff (this is the real challenge, not the schematics). Just my EUR 0.02 Kind regards, Bert Timmerman. > -----Original Message----- > From: geda-user-boun...@moria.seul.org > [mailto:geda-user-boun...@moria.seul.org] On Behalf Of Tom Hawkins > Sent: Wednesday, April 07, 2010 7:41 PM > To: gEDA user mailing list > Subject: Re: gEDA-user: hydraulic symbols and schematics > > On Wed, Apr 7, 2010 at 12:02 PM, Stuart Brorson > <s...@cloud9.net> wrote: > > Hi -- > > > >> Obviously gschem is intended for electric circuits, but has anyone > >> used it for hydraulic schematics? The hydraulics industry has > >> defined a fairly rich schematic language [1][2] for describing > >> hydraulic and pneumatic systems. > >> > >> I didn't find a gschem hydraulic symbol library, so I'm > attempting to > >> build one. My first stumbling block is the use of filled and > >> non-filled triangles, which differentiate hydraulic pumps from > >> pneumatic compressors. Is it possible to draw filled triangles or > >> polygons with gschem? > > > > I don't think vanilla gschem currently supports filled > regions. But > > this is a frequently requested feature, and the folks in > Cambridge may > > have coded up a solution based upon the whizzy graphic work > they have > > done. > > Well it appears to fill circles and boxes just fine. Maybe > it just needs the ability to handle arbitrary polygons. > > > > >> Do you foresee any other difficulties? ... aside from > simulating a > >> hydraulic circuit with spice or generating a layout. > > > > Actually, my first thought was: What kinds of simulations (if any) > > does one do in hydraulics? Are there any standard > simulators? If so, > > generating a netlist to feed to such a simulator might be an > > interesting hobby project. > > We use Easy5 and Simulink. But Easy5 doesn't run on Linux > and both tools are very clunky and neither have a standard > format. This year I plan to build some tools in this space. > It would be cool to netlist a hydraulic design out of gschem > and simulate it with other stuff like embedded software and > vehicle dynamics. > > If you look at some hydraulic schematics, you'll see a rich > duality between electric and hydraulic circuits. For > example, the pressure drop across an orifice is analogous to > the voltage drop across a resistor. Hydraulic power is > pressure * flow (i.e. V * I). > > > > >> (BTW at Eaton, we have a history of bending EDA tools for our > >> purposes. We used GTKWave to view and analyze vehicle data in > >> realtime.) > > > > Awesome! How did you get the real time info into GTKWave? IIRC, it > > only reads .vsd (and other simulation) files. > > We extract vehicle data via. a CAN bus. We then convert the > streaming CSV data into VCD and pipe this into GTKWave. The > command line reads: > > $ readCAN | tovcd - | shmidcat | gtkwave -v -I my.sav > > We put a laptop in the passenger seat when we take our test > vehicles out for a drive. With the analog features of > GTKWave, you can see all the vehicle data varying in > realtime. It's really cool. > > > _______________________________________________ > geda-user mailing list > geda-user@moria.seul.org > http://www.seul.org/cgi-bin/mailman/listinfo/geda-user > > _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user