3DDave
Aerospace
- May 23, 2013
- 10,689
I have attached a spreadsheet called GDT Battleship (.xlsx) which pits players against the GDT concepts. It has nothing to do with the trademarked game except there is a grid and you pick cells within it.
The way to play is to pick a characteristic from the columns across the top and a tolerance modifier for that characteristic and then pick from the rows down the side a characteristic (or use as a datum reference) and a modifier. It sticks to the basics for tolerance modifiers, so no "U" or Projection, et al. Obviously RFS is no longer explicit - because why make things explicit and a simple regular expression - but it needs to be in this table and if I left it blank (as it is in feature control frames) there would be complaints. (Narrator: There will be complaints anyway)
Fortunately in 2018 two of the choices were eliminated so no worries about symmetry or concentricity.
The goal for the player is to fill in every single possible combination where each column geometric characteristic and modifier combination is paired with another geometric characteristic description of the exact same feature or, as in the top most set, refer to it as a datum feature. These are in single/separate feature control frames. As discussed below not within composite tolerance feature control frames.
For example. If a hole has a position tolerance defined using the MMC modifier in one feature control frame - create a justification to use it as a datum feature reference at LMC in a different feature control frame for the same feature.
The bonus version of the game includes composite tolerances where different geometric tolerance modifiers are used at each level (MMC in the top level, LMC in the second, and RFS in the third. This version will be released when this game is completed.
The trick is that while some of these entries and combinations of entries are currently proscribed in the standard, all of them can fall under the "imagine someone could find a use and therefore it should be considered."
Some will be trickier than others. For example, flatness is applied to both a surface and to a derived middle plane (which won't actually be a plane but instead will represent deviations from the whatever the surface of median points would be called if not usurped in this inadequate use.) I could increase the columns and rows to account for these variations but assume these are all applied to enveloping features to keep it simple.
Right now there are 1404 empty spaces, suggesting at least 1404 arguments are to be had. At one or two a week this can be all filled up just after the next 2 versions of Y14.5 are released. Or one, if they settle back to the old schedule.
I presume many of these have already been discussed, some are already in the various versions of the picture book.
For individual arguments, the naming convention is "Characteristic - Material Modifier VS Characteristic - Material Modifier" or "Characteristic - Material Modifier VS Datum Feature - Material Modifier"
So "Straightness - LMC VS Position - RFS"
Link back to this post and update this thread with links to the various arguments.
In a professional setting I would expect a depiction of an actual mechanism to show how each argument works and a tolerance analysis to show the expected result so that everyone can have a working example to validate. In this game, pure speculation is fine. For example, my previous posting of a Geogebra based interactive functioning example (thread1103-507550) of how projected tolerances work. Nice to have, but not required.
Finally - the goal is to have each entry be linked to an argument supporting it. If anyone thinks some location should not be valid - that's not this game. No - is not an argument. "It's not in the standard" is not an argument. "There is a rule against it" is especially not an argument. Points are for proving an entry has a use. No points for saying there is no use.
The way to play is to pick a characteristic from the columns across the top and a tolerance modifier for that characteristic and then pick from the rows down the side a characteristic (or use as a datum reference) and a modifier. It sticks to the basics for tolerance modifiers, so no "U" or Projection, et al. Obviously RFS is no longer explicit - because why make things explicit and a simple regular expression - but it needs to be in this table and if I left it blank (as it is in feature control frames) there would be complaints. (Narrator: There will be complaints anyway)
Fortunately in 2018 two of the choices were eliminated so no worries about symmetry or concentricity.
The goal for the player is to fill in every single possible combination where each column geometric characteristic and modifier combination is paired with another geometric characteristic description of the exact same feature or, as in the top most set, refer to it as a datum feature. These are in single/separate feature control frames. As discussed below not within composite tolerance feature control frames.
For example. If a hole has a position tolerance defined using the MMC modifier in one feature control frame - create a justification to use it as a datum feature reference at LMC in a different feature control frame for the same feature.
The bonus version of the game includes composite tolerances where different geometric tolerance modifiers are used at each level (MMC in the top level, LMC in the second, and RFS in the third. This version will be released when this game is completed.
The trick is that while some of these entries and combinations of entries are currently proscribed in the standard, all of them can fall under the "imagine someone could find a use and therefore it should be considered."
Some will be trickier than others. For example, flatness is applied to both a surface and to a derived middle plane (which won't actually be a plane but instead will represent deviations from the whatever the surface of median points would be called if not usurped in this inadequate use.) I could increase the columns and rows to account for these variations but assume these are all applied to enveloping features to keep it simple.
Right now there are 1404 empty spaces, suggesting at least 1404 arguments are to be had. At one or two a week this can be all filled up just after the next 2 versions of Y14.5 are released. Or one, if they settle back to the old schedule.
I presume many of these have already been discussed, some are already in the various versions of the picture book.
For individual arguments, the naming convention is "Characteristic - Material Modifier VS Characteristic - Material Modifier" or "Characteristic - Material Modifier VS Datum Feature - Material Modifier"
So "Straightness - LMC VS Position - RFS"
Link back to this post and update this thread with links to the various arguments.
In a professional setting I would expect a depiction of an actual mechanism to show how each argument works and a tolerance analysis to show the expected result so that everyone can have a working example to validate. In this game, pure speculation is fine. For example, my previous posting of a Geogebra based interactive functioning example (thread1103-507550) of how projected tolerances work. Nice to have, but not required.
Finally - the goal is to have each entry be linked to an argument supporting it. If anyone thinks some location should not be valid - that's not this game. No - is not an argument. "It's not in the standard" is not an argument. "There is a rule against it" is especially not an argument. Points are for proving an entry has a use. No points for saying there is no use.