Re: [CF-metadata] Platform Heave

Wed, 29 Aug 2018 08:04:20 -0700 

Hi.
I've finally gotten back to this topic! The definitions below call out an attribute named "direction" that is used to specify the direction for positive values of the different quantities. We may need to add a definition for the attribute to the Conventions. The values and meanings for the direction attribute are:
roll: "clockwise" for positive right side up and "anticlockwise" for positive right side down. pitch: "clockwise" for positive nose up and "anticlockwise" for positive nose down. yaw: "clockwise" for positive nose right and "anticlockwise" for positive nose left. 
surge: "positive" for positive forward and "negative" for positive backward.
sway: "positive" for positive left and "negative" for positive right.
heave: "positive" for positive up and "negative" for positive down.

And here are the standard name definitions:
platform_roll: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Roll is a rotation about an axis (the X axis) that is perpendicular to the local vertical axis (the Z axis) and is coplanar with the nominal forward motion direction of the platform. Roll is relative to the “at rest” rotation of the platform with respect to the X axis. The “at rest” rotation of the platform may change over time. The direction for positive values of roll is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of roll represent the right side of the platform rising as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of roll represent the right side of the platform falling. The directionality of roll values is unspecified if no direction attribute is present.
platform_pitch: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Pitch is a rotation about an axis (the Y axis) that is perpendicular to both the local vertical axis (the Z axis) and the nominal forward motion direction of the platform. Pitch is relative to the “at rest” rotation of the platform with respect to the Y axis. The “at rest” rotation of the platform may change over time. The direction for positive values of pitch is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of pitch represent the front of the platform rising as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of pitch represent the front of the platform falling. The directionality of pitch values is unspecified if no direction attribute is present.
platform_yaw: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Yaw is a rotation about the local vertical axis (the Z axis). Yaw is relative to the “at rest” rotation of the platform with respect to the Z axis. The “at rest” rotation of the platform may change over time. The direction for positive values of yaw is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of yaw represent the front of the platform moving to the right as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of yaw represent the front of the platform moving to the left. The directionality of yaw values is unspecified if no direction attribute is present.
platform_surge: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Surge is a displacement along an axis (the X axis) that is perpendicular to the local vertical axis (the Z axis) and is coplanar with the nominal forward motion direction of the platform. Surge is relative to the “at rest” position of the platform with respect to the X axis. The “at rest” position of the platform may change over time. The direction for positive values of surge is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of surge represent the platform moving forward as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of surge represent the platform moving backward. The directionality of surge values is unspecified if no direction attribute is present.
platform_sway: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Sway is a displacement along an axis (the Y axis) that is perpendicular to both the local vertical axis (the Z axis) and the nominal forward motion direction of the platform. Sway is relative to the “at rest” position of the platform with respect to the Y axis. The “at rest” position of the platform may change over time.  The direction for positive values of sway is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of sway represent the platform moving left as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of sway represent the platform moving right. The directionality of sway values is unspecified if no direction attribute is present.
platform_heave: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Heave is a displacement along the local vertical axis (the Z axis). Heave is relative to the “at rest” position of the platform with respect to the Z axis. The “at rest” position of the platform may change over time.  The direction for positive values of heave is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of heave represent the platform moving up as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of heave represent the platform moving down. The directionality of heave values is unspecified if no direction attribute is present.
platform_course: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Course is the clockwise angle with respect to North of the nominal forward motion direction of the platform.
platform_orientation: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Orientation is the clockwise angle with respect to North of the longitudinal (front-to-back) axis of the platform, which may be different than the platform course (see platform_course).
platform_roll_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Roll rate is the rate of rotation about an axis (the X axis) that is perpendicular to the local vertical axis (the Z axis) and is coplanar with the nominal forward motion direction of the platform. Roll rate might not include changes in the “at rest” rotation of the platform, which may change over time. The direction for positive values of roll rate is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of roll rate represent the right side of the platform rising as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of roll rate represent the right side of the platform falling. The directionality of roll rate values is unspecified if no direction attribute is present.
platform_pitch_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Pitch rate is the rate of rotation about an axis (the Y axis) that is perpendicular to both the local vertical axis (the Z axis) and the nominal forward motion direction of the platform. Pitch rate might not include changes in the “at rest” rotation of the platform, which may change over time. The direction for positive values of pitch rate is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of pitch rate represent the front of the platform rising as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of pitch rate represent the front of the platform falling. The directionality of pitch rate values is unspecified if no direction attribute is present.
platform_yaw_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Yaw rate is the rate of rotation about the local vertical axis (the Z axis). Yaw rate might not include changes in the “at rest” rotation of the platform, which may change over time. The direction for positive values of yaw rate is specified by an attribute named direction. The value of the direction attribute is "clockwise" if positive values of yaw rate represent the front of the platform moving to the right as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "anticlockwise" if positive values of yaw rate represent the front of the platform moving to the left. The directionality of yaw rate values is unspecified if no direction attribute is present.
platform_surge_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Surge rate is the rate of displacement along an axis (the X axis) that is perpendicular to the local vertical axis (the Z axis) and is coplanar with the nominal forward motion direction of the platform. Surge rate might not include changes in the “at rest” position of the platform, which may change over time. The direction for positive values of surge rate is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of surge rate represent the platform moving forward as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of surge rate represent the platform moving backward. The directionality of surge rate values is unspecified if no direction attribute is present.
platform_sway_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Sway rate is the rate of displacement along an axis (the Y axis) that is perpendicular to both the local vertical axis (the Z axis) and the nominal forward motion direction of the platform. Sway rate might not include changes in the “at rest” position of the platform, which may change over time. The direction for positive values of sway rate is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of sway rate represent the platform moving left as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of sway rate represent the platform moving right. The directionality of sway rate values is unspecified if no direction attribute is present.
platform_heave_rate: Platform is a structure or vehicle that serves as a base for mounting sensors. Platforms include, but are not limited to, satellites, aeroplanes, ships, buoys, ground stations, and masts. Heave rate is the rate of displacement along the local vertical axis (the Z axis). Heave rate might not include changes in the “at rest” position of the platform, which may change over time. The direction for positive values of heave rate is specified by an attribute named direction. The value of the direction attribute is "positive" if positive values of heave rate represent the platform moving up as viewed by an observer on top of the platform facing forward. The value of the direction attribute is "negative" if positive values of heave rate represent the platform moving down. The directionality of heave rate values is unspecified if no direction attribute is present. 


Grace and peace,


Jim


On 8/6/18 12:11 PM, Kenneth Kehoe wrote:

Roy,

I am specifically asking for platform_sway and platform_surge.

Thanks,

Ken



On 2018-8-6 10:02, Lowry, Roy K. wrote:


Hi Jim,
One other thing to think on is the set of 'rate' Standard Names, or are you happy with my prefix from the yaw example added on to your definitions.
And finally are we intending to propose platform_sway and platform_surge as new Standard Names in addition to platform_heave which started this discussion even though nobody has specifically asked for them? 


Cheers, Roy.
I have now retired but will continue to be active through an Emeritus Fellowship using this e-mail address. 



------------------------------------------------------------------------
*From:* CF-metadata <[email protected]> on behalf of Jim Biard <[email protected]> 
*Sent:* 06 August 2018 16:47
*To:* CF Metadata List; Jonathan Gregory
*Subject:* Re: [CF-metadata] Platform Heave
Hi.
There are other standard names that call for a separate attribute or variable that provides context. The attributes (at the moment) are all standard CF attributes (cell_methods, flag_meanings, comment, etc). I'd love to get feedback from the community about whether or not a directionality attribute would need to described as a "standard" CF attribute.
I'll be glad to rework the definitions to make them directionality-agnostic when I get back next week. 

Grace and peace,

Jim
CICS-NC <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=x34l51xPXmgH-aUwvSrR2s1BvnegDR9v5TUvmlkuC08&e=>Visit us on Facebook <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_cicsnc&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=ms-RsdZkI8VABhdzIF3uemXo55CtII0rsdo8p0EYXwM&e=> *Jim Biard* 
*Research Scholar*
Cooperative Institute for Climate and Satellites NC <https://urldefense.proofpoint.com/v2/url?u=http-3A__cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=dULLQNwecP3zJLjL5xmrBdaMifj8CGxHQVPkkTbgRRs&e=> North Carolina State University <https://urldefense.proofpoint.com/v2/url?u=http-3A__ncsu.edu_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=pc9bIRFh1dbwzMr31a0uZZsN9rtfZQW3CJ6up_ZoctU&e=> NOAA National Centers for Environmental Information <https://urldefense.proofpoint.com/v2/url?u=http-3A__ncdc.noaa.gov_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=W7I_Xw3TkOaJnM-fY_w1EGSZp2wCuNP2eAzOeeh4MPM&e=> 
/formerly NOAA’s National Climatic Data Center/
151 Patton Ave, Asheville, NC 28801
e: [email protected] <mailto:[email protected]>
o: +1 828 271 4900
/Connect with us on Facebook for climate <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=NW1KhxgkoSaNb9uaszNGr_sx0r-XF6FmCUYw7xwaxNA&e=> and ocean and geophysics <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_NOAANCEIoceangeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=Wx80mh4fB0mOGx5gusz4LetEt4drrQlVeK3qWuqbKyM&e=> information, and follow us on Twitter at @NOAANCEIclimate <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.twitter.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=uXUzJCfCczRpiT3Na_BRexKN49eJJ2XmdDofSG3SEf8&e=>and @NOAANCEIocngeo <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.twitter.com_NOAANCEIocngeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=Vli9eQ3qepClRhnPQrHBQdUsozDl_01mX3zx0S-g-rw&e=>.// 

/
On Sat, Aug 4, 2018 at 3:45 AM Lowry, Roy K. <[email protected] <mailto:[email protected]>> wrote: 

    Dear Nan,


    So are we returning to the wording in Alison's original
    definitions (e.g. yaw normally clockwise facing front) before
    you with my support asked for the ambiguity be removed? Or do you
    want to go even further with no mention of sign convention at all?


    I would also question whether a Standard Name definition is the
    place to specify the mechanism to be used for the description of
    a sign convention as it has wider implications than the
    parameters currently under discussion. Would it not be more
    appropriate for this to be considered an enhancement to CF and
    written into the Conventions document? If so, it should it not be
    the subject of a GitHub ticket?


    Cheers, Roy.


    I have now retired but will continue to be active through an
    Emeritus Fellowship using this e-mail address.



    ------------------------------------------------------------------------
    *From:* CF-metadata <[email protected]
    <mailto:[email protected]>> on behalf of Nan
    Galbraith <[email protected] <mailto:[email protected]>>
    *Sent:* 04 August 2018 02:18
    *To:* [email protected] <mailto:[email protected]>
    *Subject:* Re: [CF-metadata] Platform Heave
    Thanks, Jim.

    > change the definitions to avoid declaring which direction is
    > positive, make the direction attribute optional, and say that
    users
    > should be careful about assuming the directionality for variables
    > lacking the attribute.

    This is the approach I'd prefer as well.

    - Nan


    Quoting Jim Biard <[email protected] <mailto:[email protected]>>:

    > Nan,
    >
    > I didn't go to the lengths of making new regularized definitions
    > before I wrote that list. I was thinking in terms of making the
    > clockwise/anticlockwise call based on the right hand rule and the
    > unit vector for each axis. For roll, for example, if the X unit
    > vector faces forward, the "right side down" roll is actually
    > anticlockwise - that is, it is in the direction that your right
    hand
    > fingers curl if you grab the unit vector in your hand with your
    > thumb pointing in the same direction as the unit vector. That
    > definition is independent of observer location and look direction.
    > My definitions for all the direction values are following that
    same
    > convention.
    >
    > Accurate knowledge of the sign of roll, pitch, and yaw is critical
    > in the satellite and aircraft world. The look angles for remote
    > sensors are affected by these values. I get it that not all
    systems
    > care about the signed values, so that reason and for backward
    > compatibility I suggested that we could change the definitions to
    > avoid declaring which direction is positive, make the direction
    > attribute optional, and say that users should be careful about
    > assuming the directionality for variables lacking the attribute.
    >
    > Grace and peace,
    >
    > Jim
    >>
    >> On 8/3/18 2:03 PM, Nan Galbraith wrote:
    >>> Hi Roy -
    >>>
    >>> Yes,  I've been looking at that page quite a bit lately, and I
    >>> think it backs up
    >>> what I'm saying.
    >>>
    >>> If you are standing on that fuselage (may we never), facing
    >>> forward, the red roll
    >>> arrow is showing a clockwise motion, with right side moving
    >>> downward. If you
    >>> were facing aft, the arrow would be anticlockwise, but the
    right side would
    >>> be rising.
    >>>
    >>> So, 'roll: "clockwise" for positive right side up and
    >>> "anticlockwise" for positive right
    >>> side down'    - is backwards in either case. I'm not disputing
    >>> anything except
    >>> the term 'clockwise'  in this phrase.
    >>>
    >>> Thanks - Nan
    >>>
    >>> On 8/3/18 1:43 PM, Lowry, Roy K. wrote:
    >>>>
    >>>> Hi Nan,
    >>>>
    >>>>
    >>>> Whilst I appreciate the limitations of Wikipedia as an
    >>>> authoritative source have a look at
    >>>> https://en.wikipedia.org/wiki/Aircraft_principal_axes
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__en.wikipedia.org_wiki_Aircraft-5Fprincipal-5Faxes&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=vsq2M6-NEvFLhjrrcxFzQzHADYPYRymmMIyRAD7Eri8&e=>

    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__en.wikipedia.org_wiki_Aircraft-5Fprincipal-5Faxes&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=vsq2M6-NEvFLhjrrcxFzQzHADYPYRymmMIyRAD7Eri8&e=>
        
    Aircraft principal axes - Wikipedia
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__en.wikipedia.org_wiki_Aircraft-5Fprincipal-5Faxes&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=vsq2M6-NEvFLhjrrcxFzQzHADYPYRymmMIyRAD7Eri8&e=>
    en.wikipedia.org
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__en.wikipedia.org&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=F2oneKZNdTKs8-R1zyCWTiC3MJEk-b1hTZ2iCfnPse4&e=>
    Normal axis, or yaw axis — an axis drawn from top to bottom, and
    perpendicular to the other two axes.Parallel to the fuselage
    station.; Transverse axis, lateral axis, or pitch axis — an axis
    running from the pilot's left to right in piloted aircraft, and
    parallel to the wings of a winged aircraft.



    >>>>
    >>>>
    >>>> Cheers, Roy.
    >>>>
    >>>>
    >>>>
    ------------------------------------------------------------------------

    >>>> *From:* Nan Galbraith <[email protected]
    <mailto:[email protected]>>
    >>>> *Sent:* 03 August 2018 18:23
    >>>> *To:* Jim Biard; Lowry, Roy K.; [email protected]
    <mailto:[email protected]>
    >>>> *Subject:* Re: [CF-metadata] Platform Heave (pitch, roll)
    >>>> Hi Jim, Roy and Ken -
    >>>>
    >>>> I'm skipping the list because this is a minor point and ...
    and I may be
    >>>> missing
    >>>> something obvious.
    >>>>
    >>>> It's hard not to think of these terms as they apply to
    ships. In that
    >>>> environment,
    >>>> we'd use the convention of the observer facing forward;
    therefore roll
    >>>> would be
    >>>> clockwise if the right side were going down, not up. I'm
    supposing that
    >>>> would
    >>>> also apply to aircraft.
    >>>>
    >>>> Cheers - Nan
    >>>>
    >>>>
    >>>>
    >>>>> If we declare that X is positive forward, that Y is
    positive left,
    >>>>> that Z is positive up, and that we use the right-hand rule
    for angle
    >>>>> directions, the direction attribute values could be:
    >>>>>
    >>>>>   * roll: "clockwise" for positive right side up and
    "anticlockwise"
    >>>>>     for positive right side down.
    >>>>>   * pitch: "clockwise" for positive nose up and
    "anticlockwise" for
    >>>>>     positive nose down.
    >>>>>   * yaw: "clockwise" for positive nose right and
    "anticlockwise" for
    >>>>>     positive nose left.
    >>>>>   * surge: "positive" for positive forward and "negative" for
    >>>>>     positive backward.
    >>>>>   * sway: "positive" for positive left and "negative" for
    positive right.
    >>>>>   * heave: "positive" for positive up and "negative" for
    positive down.
    >>>>>
    >>>>
    >>>>
    >>>>>
    >>>>>>>
    >>>>>>>
    ------------------------------------------------------------------------

    >>>>>>> >>>
    >>>>>>> *From:* CF-metadata <[email protected]
    <mailto:[email protected]>> on behalf of
    >>>>>>> Jim Biard <[email protected] <mailto:[email protected]>>
    >>>>>>> *Sent:* 03 August 2018 15:41
    >>>>>>> *To:* [email protected]
    <mailto:[email protected]>
    >>>>>>> *Subject:* Re: [CF-metadata] Platform Heave
    >>>>>>>
    >>>>>>> I freely admit that I picked direction on sway
    arbitrarily. In my
    >>>>>>> experience, part of the variation that arises in the
    definitions of
    >>>>>>> the different motions arises from different thoughts
    about their
    >>>>>>> use, particularly whether someone is thinking the values
    are used to
    >>>>>>> transform into the platform body frame vs transform from
    it. Or
    >>>>>>> maybe they just aren't worrying about consistency. Like
    as not,
    >>>>>>> choices have often been made in attempts to make the
    values have the
    >>>>>>> signed-ness that felt right to people, and we can't keep to
    >>>>>>> conventions like the right hand rule and make it all work
    >>>>>>> consistently. We want a positive pitch to be nose up. We
    want a
    >>>>>>> positive yaw to be nose right. We want positive heave to
    be up. My
    >>>>>>> natural tendency is to think of "roll right" as positive
    and "sway
    >>>>>>> right" as positive, but that isn't what other people
    think of.
    >>>>>>>
    >>>>>>> As I read what I wrote, I realize I didn't use a
    consistent approach
    >>>>>>> to position and look direction when assigning clockwise and
    >>>>>>> anticlockwise to roll, pitch, and yaw. I need to
    regularize that.
    >>>>>>>
    >>>>>>> Reading the Conventions about vertical coordinates, it
    says they
    >>>>>>> must all have a "positive" attribute with a value of "up"
    or "down".
    >>>>>>> I don't see a problem with having the definitions back off of
    >>>>>>> declaring a specific directionality and add an attribute
    declaring
    >>>>>>> directionality. We could call the attribute "direction"
    so as not to
    >>>>>>> step on the "positive" attribute, and say that if the
    attribute is
    >>>>>>> not present that the user should not assume which
    direction is correct.
    >>>>>>>
    >>>>>>> If we declare that X is positive forward, that Y is
    positive left,
    >>>>>>> that Z is positive up, and that we use the right-hand
    rule for angle
    >>>>>>> directions, the direction attribute values could be:
    >>>>>>>
    >>>>>>>   * roll: "clockwise" for positive right side up and
    "anticlockwise"
    >>>>>>>     for positive right side down.
    >>>>>>>   * pitch: "clockwise" for positive nose up and
    "anticlockwise" for
    >>>>>>> positive nose down.
    >>>>>>>   * yaw: "clockwise" for positive nose right and
    "anticlockwise" for
    >>>>>>> positive nose left.
    >>>>>>>   * surge: "positive" for positive forward and "negative" for
    >>>>>>> positive backward.
    >>>>>>>   * sway: "positive" for positive left and "negative" for
    positive
    >>>>>>> right.
    >>>>>>>   * heave: "positive" for positive up and "negative" for
    positive down.
    >>>>>>>
    >>>>>>> Thoughts?
    >>>>>>>
    >>>>>>> BTW, I'll be out until August 13.
    >>>>>>>
    >>>>>>> Grace and peace,
    >>>>>>>
    >>>>>>> Jim
    >>>>>>>
    >>>
    >>>
    >>
    >> --
    >> CICS-NC <http://www.cicsnc.org/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=x34l51xPXmgH-aUwvSrR2s1BvnegDR9v5TUvmlkuC08&e=>>
    Visit us on
    >> Facebook <http://www.facebook.com/cicsnc
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_cicsnc&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=ms-RsdZkI8VABhdzIF3uemXo55CtII0rsdo8p0EYXwM&e=>>
    *Jim Biard*
    >> *Research Scholar*
    >> Cooperative Institute for Climate and Satellites NC
    <http://cicsnc.org/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=dULLQNwecP3zJLjL5xmrBdaMifj8CGxHQVPkkTbgRRs&e=>>
    >> North Carolina State University <http://ncsu.edu/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__ncsu.edu_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=pc9bIRFh1dbwzMr31a0uZZsN9rtfZQW3CJ6up_ZoctU&e=>>
    >> NOAA National Centers for Environmental Information
    <http://ncdc.noaa.gov/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__ncdc.noaa.gov_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=W7I_Xw3TkOaJnM-fY_w1EGSZp2wCuNP2eAzOeeh4MPM&e=>>
    >> /formerly NOAA?s National Climatic Data Center/
    >> 151 Patton Ave, Asheville, NC 28801
    >> e: [email protected] <mailto:[email protected]>
    <mailto:[email protected]>
    >> o: +1 828 271 4900
    >>
    >> /Connect with us on Facebook for climate
    >> <https://www.facebook.com/NOAANCEIclimate
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=OmKVyuX-vwrLbBn43W4Y27Y_-KHO1WJTVr5xjI3BEck&e=>>
    and ocean and geophysics
    >> <https://www.facebook.com/NOAANCEIoceangeo
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIoceangeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=7Bc5J9zHYQ9FmY2Z15-varm_gGauDkwVQT0rEeYLbvE&e=>>
    information, and follow
    >> us on Twitter at @NOAANCEIclimate
    >> <https://twitter.com/NOAANCEIclimate
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=pPhOtc6iLld2pkJM12Q3xCbFT6ui5aXr4xB1FLPyJoo&e=>>
    and @NOAANCEIocngeo
    >> <https://twitter.com/NOAANCEIocngeo
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIocngeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=SoEnBZw_EODW-MfrLWXeaXZaRA9JZTU4dZSUxHXDz7Y&e=>>.
    /
    >>
    >>
    >
    > --
    > CICS-NC <http://www.cicsnc.org/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=x34l51xPXmgH-aUwvSrR2s1BvnegDR9v5TUvmlkuC08&e=>>
    Visit us on
    > Facebook <http://www.facebook.com/cicsnc
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.facebook.com_cicsnc&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=ms-RsdZkI8VABhdzIF3uemXo55CtII0rsdo8p0EYXwM&e=>>
    *Jim Biard*
    > *Research Scholar*
    > Cooperative Institute for Climate and Satellites NC
    <http://cicsnc.org/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__cicsnc.org_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=dULLQNwecP3zJLjL5xmrBdaMifj8CGxHQVPkkTbgRRs&e=>>
    > North Carolina State University <http://ncsu.edu/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__ncsu.edu_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=pc9bIRFh1dbwzMr31a0uZZsN9rtfZQW3CJ6up_ZoctU&e=>>
    > NOAA National Centers for Environmental Information
    <http://ncdc.noaa.gov/
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__ncdc.noaa.gov_&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=W7I_Xw3TkOaJnM-fY_w1EGSZp2wCuNP2eAzOeeh4MPM&e=>>
    > /formerly NOAA?s National Climatic Data Center/
    > 151 Patton Ave, Asheville, NC 28801
    > e: [email protected] <mailto:[email protected]>
    <mailto:[email protected]>
    > o: +1 828 271 4900
    >
    > /Connect with us on Facebook for climate
    > <https://www.facebook.com/NOAANCEIclimate
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=OmKVyuX-vwrLbBn43W4Y27Y_-KHO1WJTVr5xjI3BEck&e=>>
    and ocean and geophysics
    > <https://www.facebook.com/NOAANCEIoceangeo
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.facebook.com_NOAANCEIoceangeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=7Bc5J9zHYQ9FmY2Z15-varm_gGauDkwVQT0rEeYLbvE&e=>>
    information, and follow
    > us on Twitter at @NOAANCEIclimate
    > <https://twitter.com/NOAANCEIclimate
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIclimate&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=pPhOtc6iLld2pkJM12Q3xCbFT6ui5aXr4xB1FLPyJoo&e=>>
    and @NOAANCEIocngeo
    > <https://twitter.com/NOAANCEIocngeo
    
<https://urldefense.proofpoint.com/v2/url?u=https-3A__twitter.com_NOAANCEIocngeo&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=SoEnBZw_EODW-MfrLWXeaXZaRA9JZTU4dZSUxHXDz7Y&e=>>.
    /



    _______________________________________________
    CF-metadata mailing list
    [email protected] <mailto:[email protected]>
    http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=moY1cpYrXWj2J0PJahnBfzD3W59dtgVVmQlpZWZ8CEo&e=>
    ------------------------------------------------------------------------
    This message (and any attachments) is for the recipient only.
    NERC is subject to the Freedom of Information Act 2000 and the
    contents of this email and any reply you make may be disclosed by
    NERC unless it is exempt from release under the Act. Any material
    supplied to NERC may be stored in an electronic records
    management system.
    ------------------------------------------------------------------------
    _______________________________________________
    CF-metadata mailing list
    [email protected] <mailto:[email protected]>
    http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
    
<https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.cgd.ucar.edu_mailman_listinfo_cf-2Dmetadata&d=DwMF-g&c=qKdtBuuu6dQK9MsRUVJ2DPXW6oayO8fu4TfEHS8sGNk&r=Vm7o2ZGxPkkqRuPs8nVMVQ&m=uVfoFv-LtZ2x4jvCcYtHX-YLw4uUnDgUjlQ0IOZ9PxQ&s=moY1cpYrXWj2J0PJahnBfzD3W59dtgVVmQlpZWZ8CEo&e=>

------------------------------------------------------------------------
This message (and any attachments) is for the recipient only. NERC is subject to the Freedom of Information Act 2000 and the contents of this email and any reply you make may be disclosed by NERC unless it is exempt from release under the Act. Any material supplied to NERC may be stored in an electronic records management system. 
------------------------------------------------------------------------

_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata


--
Kenneth E. Kehoe
   Research Associate - University of Oklahoma
   Cooperative Institute for Mesoscale Meteorological Studies
   ARM Climate Research Facility - Data Quality Office
   e-mail:[email protected]  | Office: 303-497-4754 | Cell: 405-826-0299



_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata


--
CICS-NC <http://www.cicsnc.org/> Visit us on
Facebook <http://www.facebook.com/cicsnc>         *Jim Biard*
*Research Scholar*
Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/>
North Carolina State University <http://ncsu.edu/>
NOAA National Centers for Environmental Information <http://ncdc.noaa.gov/>
/formerly NOAA’s National Climatic Data Center/
151 Patton Ave, Asheville, NC 28801
e: [email protected] <mailto:[email protected]>
o: +1 828 271 4900
/Connect with us on Facebook for climate <https://www.facebook.com/NOAANCEIclimate> and ocean and geophysics <https://www.facebook.com/NOAANCEIoceangeo> information, and follow us on Twitter at @NOAANCEIclimate <https://twitter.com/NOAANCEIclimate> and @NOAANCEIocngeo <https://twitter.com/NOAANCEIocngeo>. / 



_______________________________________________
CF-metadata mailing list
[email protected]
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata

Reply via email to