Re: [Emc-users] Mastering mixed units [Was: Re: Large servo selection

[Erik Christiansen]

On 12.04.18 04:02, jeremy youngs wrote:
> You just invoke $ units in terminal and punch the conversion you want ?
> That's awesome

Yup, it is awfully convenient, e.g.:
 # For stepper motors:
   You have: 280 oz force in # There's no "ozf".
   You want: N m # There is a conformability error if the
   * 1.9772345   # oz isn't made oz force.
   / 0.5057569   # See: "force" toward end of the manpage.

   If you muck up the units by forgetting the "force", it tells you.

   Some other examples:

   You have: 1 fathom^3 waterdensity # Water mass
   You want: tons
   * 6.7422197
   / 0.14831911

   Water depth equal to one atmosphere:  # Water column
   You have: atm
   You want: ft water
   * 33.898538
   / 0.029499797

   And a couple I used recently:
  # PV Cable: Resistance of 16 m:
   You have: 16m/(copperconductivity * 4 mm^2)
   You want: ohms
   * 0.068965517
   / 14.5

  # PV Cable: Power Loss @ 8 amps:
   You have: (8 A)^2 * 16m/(copperconductivity * 4 mm^2)
   You want: W
   * 4.4137931
   / 0.2265625

Beats using a sliderule.

   Erik

--
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Mastering mixed units [Was: Re: Large servo selection

[jeremy youngs]

You just invoke $ units in terminal and punch the conversion you want ?
That's awesome

On Wed, Apr 11, 2018, 21:14 Erik Christiansen 
wrote:

> On 11.04.18 15:08, John Kasunich wrote:
> > On Wed, Apr 11, 2018, at 10:30 AM, David Berndt wrote:
> > > I'm looking to output about 1000lbf in a linear direction via a
> > > crank/slider or ballscrew with peak speed of about 1m/s. So that's a
> real
> > > 5hp of energy.
> >
> > Mixed units are making my head hurt
> >
> > 1000lbf = 4448 newtons I think?
> > At 1m/s, that is 4448 watts.  1 HP = 746 watts, so 4454 watts = 5.96HP.
>
> Yup, that'd make my eyes water too ... unless we're on linux:
>
> $ units
> ...
> You have: 1000 lbf * 1 m/s
> You want: hp
> * 5.9651634
> / 0.16764
>
> The reciprocal conversion can be suppressed by invoking "units -1".
>
> Erik
>
>
> --
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
--
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users