I was making a few assumptions, like, the rocket is instrumented
acceleration, position (gps), pressure, ..... all the things on today's
standard phone. So a Hydrogen Engine test could use these instruments to
determine performance with no mass.
On Tue, Jul 31, 2018 at 2:00 PM Edward Wranosky <edwardcw@xxxxxxxxx> wrote:
I should have phrased my original question differently - what is the
minimum mass for a more complicated payload that doesn't just report
vehicle status, etc. That actually conducts a scientific experiement.
Edward
On Tue, Jul 31, 2018 at 12:18 PM Shepherd Kruse <
shepherd.h.kruse@xxxxxxxxx> wrote:
Ed,
I’ve worked on balloon payloads and more specifically Pico balloon
payloads. So with 8g not including battery, I can get velocity, altitude,
latitude, longitude, temperature, and send that data back using a small
APRS transmission chip. So for me that’s quite a lot of data with a very
low weight, but once cameras and possibly robotics are added, the weight
will go up quite a bit.
On Tue, Jul 31, 2018 at 11:42 AM Edward Wranosky <edwardcw@xxxxxxxxx>
wrote:
What is the minimum mass for a 'useful' payload?
Edward
On Tue, Jul 31, 2018 at 9:04 AM Shepherd Kruse <
shepherd.h.kruse@xxxxxxxxx> wrote:
Thank you guys for the insight. I’ll start looking into how feasible it
would be to carry out some of these experiments.
Shepherd
On Tue, Jul 31, 2018 at 8:38 AM William Claybaugh <
wclaybaugh2@xxxxxxxxx> wrote:
John:
If you have GPS on board using a camera for altitude estimation is
pointless. At 50 (statute) miles the error is estimating the bulge of the
earth in a limb image—assuming a “normal” focal length—is order + / - 5%;
GPS is accurate to meters.
Bill
On Tue, Jul 31, 2018 at 9:23 AM John Stoffel <john@xxxxxxxxxxx> wrote:
"William" == William Claybaugh <wclaybaugh2@xxxxxxxxx> writes:
William> Camera calibration consists of measuring the field of view
William> upon recovery; the rest is just monkey motion that provides
William> no useful insight.
I don't agree, because that monkey motion involves something new to
the team doing the work, and since they're a student/amateur group,
they don't have the expertise (probably) to do more esoteric work.
And they have just 1lb to work with. So getting fundamentally new
science work to fit into that space/mass is a project in and of
itself.
William> Exactly this technique was used—off duty—by staff at JPL to
William> estimate the height at which an image was taken during the
William> RRS Dart flight of 1996; the relevant variance analysis had
William> to do with the ability to measure the bulge in the Earth
William> horizon image, which was accounted for in the analysis as
William> documented in the article currently available at rrs.org.
Now that paper might be a great start, and now they can work to
miniaturize this type of sensor system so that it's trivial for others
to use down the line.
William> If one insists upon correlative data, it can be had from
William> direct imaging of the ground—as was done w/ the RRS Dart
William> data. Correlating w/ GPS or any alternative data source is
William> merely redundant to what is already proven.
William> The rest of what you propose apoears—to me—to be utterly
William> irrelevant: it is—in my experience—a waste of effort and
William> money to spend time on problems the answers to which can not
William> effect the certainty of our existing knowledge.
I view this project as an opportunity to learn something new, which
involves the entire process from start to finish, not just the
science results generated.
John