Mars Rover Opportunity Update: June 21-24, 2013

In article ,
says...

"bob haller" wrote in message
...

well the cost of a repairman on site could be too high, making it cheaper
to just replace it. this is why a lot of equiptement is replaced. sure it
can be fixed but economically its not worth it....

lets assume travel to fix that pot is 100 bucks a hour times 3 year round
trip

Lets assume something far more realistic.

A crewed mission with 4-6 people (my guess at the most likely number) what
is supplemented with rovers on the ground.

As I've pointed out and Jeff is alluding to, it's NOT an either/or
situation. Most likely it will be a AND situation.

I can certainly see a scenario where the rovers are driven from the landing
craft or even Earth overnight to check out things the astronauts don't have
time for. If they find something of interest, the astronauts wonder over and
check it out.

And if you're not nearly as worried about your rover getting stuck, etc. you
can "drive" it a lot faster.

Plus, if there is someone available to drive the rover remotely, from a
Mars lander or habitat module, then the round trip radio signal time
delay becomes so short that it can be driven in real-time. This is
*huge* since the time delay to earth is so long that every single
command to move a rover must be carefully planned and thought out in
order to keep it from getting stuck. Anyone that knows anything about
closed loop control system delays will apprecite this.

The risk of a remote controlled rover getting permanently stuck greatly
diminishes for a combination manned/unmanned mission where the rovers
are remotely driven and maintained.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

"Jeff Findley" wrote in message
...

In article ,
says...

"bob haller" wrote in message
...

well the cost of a repairman on site could be too high, making it
cheaper
to just replace it. this is why a lot of equiptement is replaced. sure
it
can be fixed but economically its not worth it....

lets assume travel to fix that pot is 100 bucks a hour times 3 year
round
trip

Lets assume something far more realistic.

A crewed mission with 4-6 people (my guess at the most likely number)
what
is supplemented with rovers on the ground.

As I've pointed out and Jeff is alluding to, it's NOT an either/or
situation. Most likely it will be a AND situation.

I can certainly see a scenario where the rovers are driven from the
landing
craft or even Earth overnight to check out things the astronauts don't
have
time for. If they find something of interest, the astronauts wonder over
and
check it out.

And if you're not nearly as worried about your rover getting stuck, etc.
you
can "drive" it a lot faster.

Plus, if there is someone available to drive the rover remotely, from a
Mars lander or habitat module, then the round trip radio signal time
delay becomes so short that it can be driven in real-time. This is
*huge* since the time delay to earth is so long that every single
command to move a rover must be carefully planned and thought out in
order to keep it from getting stuck. Anyone that knows anything about
closed loop control system delays will apprecite this.

Agreed. I suspect though they might try a combination.

Keep the Mars crew all on the same shift and "overnight" due some driving
from Earth. But it might not be worth it.


The risk of a remote controlled rover getting permanently stuck greatly
diminishes for a combination manned/unmanned mission where the rovers
are remotely driven and maintained.

Ayup.



Jeff

--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

send so many rovers that some lost for any numbers of reasons isnt a big deal.....

you could also have flying repair robots to do repairs when possible..

well any manned equiptement is way more complex and costly than unmanned.. so they are more prone to breakdowns........

and obviously a manned system with a major failure can cause deaths.

and building in triple redundacies adds costs. and the added complexity, it just gets worse

thus far mercury, gemini, apollo, and shuttles were designed with little or no in flight repair ability by astronauts....

the one exception is ISS which requires constant repairs....

now with a mult year mars mission some repairs will lkely occur, but with home so far away triple redundancy will likely be the first design spec, followed by easy to replace parts.....

Le 01/07/13 19:06, Jeff Findley a écrit :
A drive was planned on Sol 3350 (June 26, 2013), and stopped almost immediately
due to an even larger anomalous reading of that same potentiometer. The
plan ahead is to conduct a set of diagnostics on the joint potentiometer.

I bet a good squirt of DeoxIT would fix that potentiometer issue...


Arthritis.

Opportunity is old, and its parts begin to fail.

Like us, she has knee problems in old age.

Considering how badly designed that knee is, without any
backup, it is astounding that this happens after TEN years.

And how easy is, to imagine two robots, and each one of them
gives a fix of DeoxIT to the other.

Two robots in a couple can fix themselves, or help themselves out of
a sand trap.

The sand trap that killed Spirit would have been fixable if Oppy
would have been nearby: It is highly unlikely that that sand trap
would happen to both of them if they travel in formation around 30
meters from each other.

The next country that sends machines over there, could send them
in couples.

Send men. It's cheaper and you'll get about 3 orders of magnitude
more done (and done better).

so people are cheaper than robot rovers....

you are delusional sending humans cost boatloads of money.

If thats not true why havent we sent humans?

Le 07/07/13 01:32, Fred J. McCall a écrit :
Send men. It's cheaper

Men are nothing without their WOmen.

Isolated humans are quite more fragile than the ones living in couple.

What a strange coincidence isn't it?

:-)

But humans are complicated. Married are better off than singles, but
living in a bad marriage is even worst than living as a single...

Happily, robots have no such problems... until now, that is.

In article ,
says...

send so many rovers that some lost for any numbers of reasons isnt a big deal.....

You've been told repeatedly why this isn't being done.

you could also have flying repair robots to do repairs when possible..

Or you could have monkeys fix them, but that's only possible after they
fly out of your butt.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In article ,
says...

well any manned equiptement is way more complex and costly than unmanned.. so they are more prone to breakdowns........

B.S. You have no clue what complexity exists in the toasters you think
could be "mass produced". More of your typical hand waving garbage.

and obviously a manned system with a major failure can cause deaths.

So can a traffic accident, or an airliner crash, yet people still travel
by ground and by air.

and building in triple redundacies adds costs. and the added complexity, it just gets worse

Applies to both manned and unmanned craft, so what's your point?

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer