At 07:31 31/07/2009, you wrote:
/ Detecting a good tip catch is going to be an interesting
engineering problem
as the plane never really stops flying.
However I agree, it is an awesome idea. /
Hi Mark,
Obviously there are problems to solve, but the main thing is that it
can be done. We all have a natural tendency to keep what has been used
for as long as we can remember without even asking the question
whether there is another and better way.
For instance, we can imagine that the launch moment with F3B or F3J
could be detected from an electrical contact on the towhook or a
pressure gauge. With F6D or F3K we can imagine a contact detector on
the launch peg inner side or, again, with an accelerometer (the beauty
of the thing with accelerometers is that the timing system could be
entirely self-contained, just a drop-in unit in the fuselage with no
connection to be done inside the glider, even electrical power could
be in). Then the moment of catch or landing could be defined in the
software with something such as: contact with the peg *OR *positive
lateral acceleration (a tip catch)* OR *negative longitudinal
acceleration (a landing). As said earlier, development would need
experimentations and I am sure most of you would be ready to
experiment. Another example: a landing/catch would normally be
detected with a shock detector (longitudinal accelerometer) and
experiments would be needed to define the minimal value , such as 60 G
/ 0.05 s (a small shock) or maybe 30 G / 0.5 s (a catch), etc. The
main thing is that we must decide to launch the project, then built up
a group of specialists in the needed domains (software, electronics,
etc.). Finding the suitable detection methods is a matter of defining
what /may /be suitable, then experimenting to validate it.
We may need one, three or five years or more to develop a suitable
system, but the basic thing is : do you really believe that, if
nothing is done, in ten of fifteen years from now we will still be
using hand held stopwatches (if such outdated devices are still
available) to select a winner in a duration or speed event or at an
F3J World Championship ?
At this time, the only question is : do you think it worthwhile to
start the project ? If yes, then we'll have to find the proper
specialists (probably mostly out of our group) and begin development.
Tomas mentioned that he approached Jeti and that they may be willing
to work on such a project, but before this stage we must first define
what we want.
So please, are you in favour or not ?
This leaves the initial question unanswered : what are your proposals
to break a tie in the final round ? At least for 2011 and probably up
to 2013 at least, we have to rely on hand held stopwatches, we need an
agreement and a firm proposal by next October.
Guy R.
