Participant
Interview:
Mike
Stapp
Electrical Engineer
PMEL Engineering Development Division
Jeff: What's
projects are you working on during NeMO 2000?
Mike: Primarily the extensometers. I'm an electronics engineer so I help
fix other electronic devices. If something breaks in the science party,
they'll probably ask me to fix it.
Jeff: How
do the acoustic extensometers work?
Mike: We are in a volcanically active area and where the scientists think
there might be spreading of the sea floor, we put 10 or 12 extensometers
opposite each other in a line, perpendicular to the spreading center.
Each extensometer will be roughly 100 meters apart. Once a day, at various
time slots, 2 units wake up and will range (measure) acoustically, like
sonar, the distance to each other. They will also measure the temperature
because it's important in order to calculate the sound velocity. We also
have extensometers 200 meters on either side to get an overlap. If one
dies, you still have data collection taking place.
Jeff: Where
are the data stored?
Mike: They store the data internally and we come by once a year with an
IR (infrared wavelength sensor) on an ROV like ROPOS. We can then control
the extensometer from a laptop on the ship. I have to work with the ROPOS
team to coordinate this process.
Jeff: How
long do the extensometers stay on the bottom of the ocean?
Mike: The updated version is designed to have a battery life of 5 years.
That way you don't have to pick it up every year, change the batteries,
and dump the data. If everything's working right all you need to do is
reset the clocks because the clocks in the extensometers drift slowly
over time.
Jeff: Were
you involved with the design of these instruments?
Mike: I did all the electronics and the software for the extensometers;
the insides of it. Chris Meinig designed the outer part of it, including
the mast, which raises 3 meters off the sea floor. The height prevents
the instruments from getting in a "shadow" zone of rocks on the bottom,
where no signal is picked up.
Jeff: What
is the best part about your job?
Mike: I like the variety because PMEL has several groups of scientists
that have different interests and projects they're working on. Our PMEL
engineering group supports all of them. When I'm not working on extensometers
I've got other things. It's nice for me to use some of my creativity though
engineering. It's how I get my kicks.
|