I went looking for good source material for a third example of descriptive parameterization.
I thought McCoy’s excellent, highly technical “Modern Exterior Ballistics” would be a good choice but concluded it was too well organized to serve as a good example. More or less, all of the parameters of interest show up in his equations as…parameters. So I set that aside.
Then I went after Conley’s “Space Vehicle Mechanisms”, but concluded that it didn’t add much to the two examples already drafted (Combustion Products, Orbital Parameters). Much of the data was tabulated (as was the latter), and most of what was not tabulated was conceptually similar in scope to the former, using the same basic thought processes. So I set that aside.
The mechanisms subject (however), reminded me of a General Specification for Space Vehicle Mechanisms (MIL-A-83577B) we used in the old days. It was a self-tailoring specification (as many General Specifications were) that contained much Statement of Work material. Many contracting agencies found such specifications very difficult to handle, because much of the content follows no modern theory of requirement structure. At one point, it was imposed on the program that eventually became the International Space Station, but was removed due to that difficulty.
I selected (more or less at random) the general requirements for Retention and Release Devices (Section 3.2.2.2.1) as a guinea pig. The inclusion of SoW (and other programmatic material) will drive quite a bit more scope into the example than for either of the other two, which makes for slow going. I’m into it…but it could be a few days yet.
On the other hand, layup is complete on the workbench top which, as you can see below, is a variant of the very old Roubo plan:
The topside is now flat:
Smoothing is yet to come, but I have first to mill the underside for installation of the two tail vises (the two long slots at the near end of the first photo) and mortise the end caps to fit.
And no, Spike doesn’t seem to care:
More to come.