Mars Curiosity Rover Experiences Short Circuit, Will Be Stationary For Days

hypnosec writes: NASA says its Mars Curiosity rover has experienced a transient short circuit. The team has halted all work from the rover temporarily while engineers analyze the situation. Telemetry data received from Curiosity indicated the short circuit, after which the vehicle followed its programmed response, stopping the arm activity underway whenthe irregularity in the electric current happened. Curiosity will stay parked as its engineers analyze the situation and figure out if any damage has been done. NASA says a transient short circuit would have little effect on the rover's operations in some systems, but it could force the team to restrict use of whatever mechanism caused the problem.

Comments

LOL ... Spring break ...

[gstoddart]

A spokesman for Curiosity said it would be taking some well deserved downtime, basking in the sunshine, and streaming "Rovers Gone Wild" videos.

The spokesman also added Curiosity is long overdue for a vacation in the Martian Riviera.

NASA officials were unavailable for comment on how Curiosity seems to have gotten a bottle of Wild Turkey, a keg, and a beer bong.

Better get the service manual, then

[50000BTU_barbecue]

Like this

http://www.amazon.com/NASA-Mar...

I'm curious myself about Curiosity, any way to get the hardware schematics for this thing? Like the real thing, not just a block diagram. How does it detect a short circuit? Just too much current sensed on this power rail = short? Or is there something more being done to analyze the kind of fault?

Re:Better get the service manual, then

[cdrudge]

I definitely wouldn't get the Haynes manual. It covers 16 model years and it's just going to be very generic drawings of the circuits that are pretty obvious anyways. Plus half the photos are just going to be stock photos that may or may not have come from an actual rover tear down. Some may be from a lunar rover...a few probably will be from Voyager or Pioneer too. The spark plug diagnosis photos though will be useful in determining if it's running rich or improperly gapped or physically damaged. Or completely missing.

Re:Better get the service manual, then

[Anonymous Coward]

And all re-assembly sections following a 5-page teardown will read "Re-assembly is the reverse of removal."

Re:Better get the service manual, then

[Ashenkase]

Actually they were the lowest bidder.

Re:Better get the service manual, then

[bobbied]

Pesky spelling thing... I took up engineering because I was horrid at spelling.....

Re:Better get the service manual, then

[tlhIngan]

Insightful, really? I think a few mods must've missed a "whoosh" somewhere.

Either that or they haven't seen how modern Haynes books have reinvented themselves given their old business pretty much evaporated once the 90s hit. (Yes, I remember the shelves of Haynes books back in the day and the modern internet has pretty much killed that business.)

Yeah, so it's a bit more complex than just a power supply sequencer and simple "power good" monitor? It's actually recording "telemetry" off its own power supply continuously, then they correlate the data later?

But can they turn off a power supply and take a resistance reading, for example? Or how about varying the voltage while monitoring the current?

In a spacecraft, because it's really difficult to bring it in for service and diagnostics if something goes wrong, you pretty much have to build in all the diagnostics as telemetry. The more information you can gather the better diagnosing you can do - and if you miss one, well, you can't go and probe it later with a multimeter.

So easily measured stuff like voltages and currents of power rails is instrumented because if something goes awry, that's all the data you have. Analog channels are cheap (they're generally multiplexed together) while sending someone to go and measure it for you is pretty expensive, if it's even possible to do.

The power supply inputs (solar panels, RTG, etc) will have current and voltages measured on each input (e.g., each solar array input channel will have voltages and currents monitored, not just the aggregate), the battery current and voltage will be monitored (maybe even on a per-cell basis), the output power rails of the power supply will be monitored, and the input power used by each instrument as well. If an instrument starts drawing significantly more current, you can tell which one it is and see how the rails dip. If the sum of the currents used by the instruments don't match the current the power supply is providing, then you have a short somewhere. If a power rail is off but you're still seeing voltage and even current, you can tell if the switch is bad, or if it's being backfed or a short is carrying power on it. Or if a rail goes out of spec (overvolt or undervolt).

It's unlikely they can turn off a rail and measure it - it's generally not too useful a measurement if you have current and voltage measured every which way.

And yes, there is other telemetry that's possible, including temperature, angle encoders (encoding positions of each servo in an instrument and maybe even the wheels, etc).

Re:Better get the service manual, then

[bobbied]

And all re-assembly sections following a 5-page teardown will read "Re-assembly is the reverse of removal."

Yea, but any disassembly that starts with "Retrieve Rover and place on jack stands with the emergency break set" is going to be impossible from the get go..

Johnny 5

[Anonymous Coward]

is alive

That picture...

[JD-1027]

I hate "selfies" (ugh, that word), but that is a selfie a robot took with hills on *Mars* in the background
That is truly amazing.

Short Circuit?

[Anonymous Coward]

So it became alive? Number 5 is alive!. You don't want robots having short circuits. Next thing you know they are dancing and saying, Beautiful Stephanie! and running from the authorities.

Re:Short Circuit?

[Anonymous Coward]

Stephanie look different?

Nice Software!

Number 5

[Nite_Hawk]

Mr. Five, Mr. Five, how do you feel?

How do I feel? I feel... ALIVE!