Free Republic
Browse · Search
General/Chat
Topics · Post Article

To: Red Badger

They had a watchdog timeout that rebooted the drone; it happened when they tried to spin the rotors up to 2400 rpm (which I have to admit is pretty fast for blades that big).

It struck me as pretty remarkable that something as fundamental as a watchdog timeout would have happened “at the job site,” so to speak, but you can’t catch every detail. Especially when the environment is as radically different as the surface of Mars.

I hope they can fix it with the new software. Bit of a long data link, but that’s why error-correcting codes were invented. NASA controlled the New Horizons spacecraft at a much longer distance.


5 posted on 04/13/2021 11:35:07 AM PDT by Steely Tom ([Voter Fraud] == [Civil War])
[ Post Reply | Private Reply | To 1 | View Replies ]


To: Steely Tom

I’ve been watching the fascinating videos about the Apollo Guidance Computer and how “restart on failure” has been one of the cardinal rules for space software ever since. Because you just can’t test and guard against everything...

Thanks to the brilliance of Margaret Hamilton.


12 posted on 04/13/2021 11:40:40 AM PDT by bigbob
[ Post Reply | Private Reply | To 5 | View Replies ]

To: Steely Tom

They probably didn’t test the power-up sequence at -60°C and in a near vacuum atmosphere.......................


14 posted on 04/13/2021 11:42:30 AM PDT by Red Badger ("We've always been at war with Climate Change, Winston."..............................)
[ Post Reply | Private Reply | To 5 | View Replies ]

To: Steely Tom; Red Badger

From the article:
“...move the new software through the rover
to the base station and then to the helicopter...”
-
I know what the rover is,
and I know what the helicopter is,
but what is “the base station”?


17 posted on 04/13/2021 11:49:22 AM PDT by Repeal The 17th (Get out of the matrix and get a real life.)
[ Post Reply | Private Reply | To 5 | View Replies ]

To: Steely Tom

They had a watchdog timeout that rebooted the drone; it happened when they tried to spin the rotors up to 2400 rpm (which I have to admit is pretty fast for blades that big).

Not enuff aaare!


24 posted on 04/13/2021 12:01:57 PM PDT by SgtHooper (If you remember the 60's, YOU WEREN'T THERE!)
[ Post Reply | Private Reply | To 5 | View Replies ]

To: Steely Tom

down here that would be impressive, 2400 rpm

thing would be shooting skyward in no time

but its such a thin atmosphere there

like swimming in air


25 posted on 04/13/2021 12:41:17 PM PDT by Secret Agent Man (Gone Galt; Not Averse to Going Bronson.)
[ Post Reply | Private Reply | To 5 | View Replies ]

To: Steely Tom
They had a watchdog timeout that rebooted the drone; it happened when they tried to spin the rotors up to 2400 rpm (which I have to admit is pretty fast for blades that big).

The rotor span is ~4 feet. (1.2m)

The larger RC helicopters here on earth have rotors that span about the same and spin about the same speed.

28 posted on 04/13/2021 12:51:41 PM PDT by Ol' Dan Tucker (For 'tis the sport to have the engineer hoist with his own petard., -- Hamlet, Act 3, Scene 4)
[ Post Reply | Private Reply | To 5 | View Replies ]

Free Republic
Browse · Search
General/Chat
Topics · Post Article


FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson