Earl Boebert
Senior Member
- Joined
- Dec 20, 2005
- Posts
- 392
- Reaction score
- 63
- Location
- Albuquerque NM USA
Well, here's the way I see it:
Assuming that our collective reverse engineering is correct, we have a device that operates according to the following logic:
There are a discrete set of AOA set points and a "gearshift" to select one. Moving the gearshift to a new setting has no effect until the grinders pressure up the hydraulics. At that point an internal feedback loop moves the foil to the new AOA setting and then stops.
So far, so good.
Now the question which remains unanswered in my mind is: how does the device react (if at all) to an uncommanded change in AOA, i.e. from wave action or some other external force on the foil? I see three options:
1. The foil is somehow locked in position, uncommanded change in AOA is not possible. No issues.
2. The device only reacts to a deviation between actual AOA and set point when a "new" set point moves relative to AOA, and ignores cases when the AOA moves relative to an existing set point. No issues.
3. If there is an uncommanded movement of the AOA, the next time the hydraulics are powered up the device moves the AOA back to where it was, equal to to the set point. This gets iffy, because now we have a feedback loop responding to a variable that has been influenced by the outside world.
As a practical matter, the rule is so sloppily written ("automatic" as in pistol, transmission, or elevator?) that there exist no grounds to argue with the decision of the measurers. They said it's OK, so it's OK, end of story.
As far as the artful dodging of the Oracle team goes, the PR crew in this event have been flatfooted from the start so there really is no meaningful conclusion that can be drawn from their manifest contempt for the intelligence of the public.
Cheers,
Earl
Assuming that our collective reverse engineering is correct, we have a device that operates according to the following logic:
There are a discrete set of AOA set points and a "gearshift" to select one. Moving the gearshift to a new setting has no effect until the grinders pressure up the hydraulics. At that point an internal feedback loop moves the foil to the new AOA setting and then stops.
So far, so good.
Now the question which remains unanswered in my mind is: how does the device react (if at all) to an uncommanded change in AOA, i.e. from wave action or some other external force on the foil? I see three options:
1. The foil is somehow locked in position, uncommanded change in AOA is not possible. No issues.
2. The device only reacts to a deviation between actual AOA and set point when a "new" set point moves relative to AOA, and ignores cases when the AOA moves relative to an existing set point. No issues.
3. If there is an uncommanded movement of the AOA, the next time the hydraulics are powered up the device moves the AOA back to where it was, equal to to the set point. This gets iffy, because now we have a feedback loop responding to a variable that has been influenced by the outside world.
As a practical matter, the rule is so sloppily written ("automatic" as in pistol, transmission, or elevator?) that there exist no grounds to argue with the decision of the measurers. They said it's OK, so it's OK, end of story.
As far as the artful dodging of the Oracle team goes, the PR crew in this event have been flatfooted from the start so there really is no meaningful conclusion that can be drawn from their manifest contempt for the intelligence of the public.
Cheers,
Earl