Design Con 2015
Breaking News
Comments
Oldest First | Newest First | Threaded View
Page 1 / 4   >   >>
DrQuine
User Rank
CEO
Preventing Upside-Down Sensors
DrQuine   7/10/2013 4:43:31 PM
NO RATINGS
The use of keyed connectors that can only be assembled one way is a good precaution to prevent reversed connections.  Of course, if the connector is wired backwards that won't help.  The second essential step is to gather baseline data and confirm that the device is operating properly. If indeed the sensor was installed upside-down, it should have been reported inverted data when standing on the launchpad. Exhaustive testing certainly proves its worth if it can catch a tiny error before it causes a huge failure.

CMathas
User Rank
Manager
Re: Preventing Upside-Down Sensors
CMathas   7/10/2013 6:11:11 PM
NO RATINGS
Huge failure is right. One would think that there would be several tests and confirmations in place before actual launch. That's a huge loss of resources based on something that should have been easily caught.

_hm
User Rank
CEO
Quality Control and testing in Space Electronics
_hm   7/10/2013 8:37:23 PM
NO RATINGS
Quality control in Space electronics is very essential. And this type of mistakes are often discovered. One common exapmple is polarized capacitor. Many times, they are mounted with polarity reversed.

Another aspect is testing. Testing is very improtant in this type of critical missions. It should try to encompass all this possibilities. And yes, poke yoke problem must also be avoided.

Tom Murphy
User Rank
Blogger
Dubious Source
Tom Murphy   7/10/2013 9:45:20 PM
NO RATINGS
I'm not sure I'd put a lot of stock in an unidentified source and the Interfax news agency. I mean -- these are rocket scientists we're talking about, and they know how to install sensors.  In any case, how would they know at this point?

LarryM99
User Rank
CEO
Re: Quality Control and testing in Space Electronics
LarryM99   7/10/2013 11:55:08 PM
NO RATINGS
We can't necessarily be too smug about this. I seem to remember an American Mars probe that sailed right past that planet because someone put a period instead of a comma in a line of FORTRAN code. I have had friends that worked on the Saturn 5 that left because of the tension of building systems that could never be completely tested prior to a launch. We may be better off today with a combination of more experience and better test equipment, but we are also building more complex systems.

Kevin Neilson
User Rank
Manager
Genesis
Kevin Neilson   7/11/2013 12:45:56 AM
NO RATINGS
Wait a second--I hope this isn't true, because this is exactly what happened with the Genesis probe.  It returned to earth and the drogue was supposed to come out after it had decelerated to a certain speed, but the accelerometers were mounted upside down so the deceleration was interpreted as acceleration and the drogue never came out and the probe cratered in the desert.

Sanjib.A
User Rank
CEO
Re: Dubious Source
Sanjib.A   7/11/2013 1:18:21 AM
NO RATINGS
@Tom: I agree with you. I am a bit skeptic about the source, which has pointed to an important sensor getting installed "Up-side Down" as the cause of the failure. Why I think so?...several reasons. One is already mentioned by Tom. Also:

1. There should have been well-established processes for design, development and manufacturing space equipments as this kind of space programs deal with huge money, reputation and safety. The process should have been rugged enough to prevent this kind of human error. If not prevented, atleast, it should have been caught in inspection or some kind of quality checking/reviews.

2. Even if it was a mistake, I think design should have had redundant sensors to take care of this kind errors. Hope not all of those were mounted "upside-down"...otherwise there must had been a serious process gap somewhere.

I don't think this kind of error getting un-detected is something which could be expected from a well settled space organization isn't it?

Tom Murphy
User Rank
Blogger
Re: Dubious Source
Tom Murphy   7/11/2013 1:28:08 AM
NO RATINGS
Good point, Sanjib.  You would think that there would be redundant systems. In the US, it's standard practice to have triple redundancy on space probes. And the monitoring stations on the ground watch every indicator.  There is certainly a possibility that this report is true, but I think there is a larger chance that the report is based on poor information.

Kevin Neilson
User Rank
Manager
Re: Dubious Source
Kevin Neilson   7/11/2013 3:34:46 AM
NO RATINGS
Genesis had redundant accelerometers.  They were all mounted backwards.

prabhakar_deosthali
User Rank
CEO
Re:
prabhakar_deosthali   7/11/2013 7:23:32 AM
NO RATINGS
It is very difficult to believe that such a mistake could have been made !

It will be interesting to know the design of the sensors- where there was an indication of how to mount them . If the basic instructions has been overlooked then it shows a poor standard of inspection and testing of a billion dollar product

 

Page 1 / 4   >   >>


Top Comments of the Week
Flash Poll
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
<b><a href=Betajet">

The Circle – The Future's Imperfect in the Present Tense
Betajet
5 comments
The Circle, a satirical, dystopian novel published in 2013 by San Francisco-based writer Dave Eggers, is about a large, very powerful technology company that combines aspects of Google, ...

Max Maxfield

Recommended Reads From the Engineer's Bookshelf
Max Maxfield
27 comments
I'm not sure if I read more than most folks or not, but I do I know that I spend quite a lot of time reading. I hate to be idle, so I always have a book or two somewhere about my person -- ...

Martin Rowe

Make This Engineering Museum a Reality
Martin Rowe
Post a comment
Vincent Valentine is a man on a mission. He wants to make the first house to ever have a telephone into a telephone museum. Without help, it may not happen.

Rich Quinnell

Making the Grade in Industrial Design
Rich Quinnell
16 comments
As every developer knows, there are the paper specifications for a product design, and then there are the real requirements. The paper specs are dry, bland, and rigidly numeric, making ...

Special Video Section
The LT8640 is a 42V, 5A synchronous step-down regulator ...
The LTC2000 high-speed DAC has low noise and excellent ...
How do you protect the load and ensure output continues to ...
General-purpose DACs have applications in instrumentation, ...
Linear Technology demonstrates its latest measurement ...
10:29
Demos from Maxim Integrated at Electronica 2014 show ...
Bosch CEO Stefan Finkbeiner shows off latest combo and ...
STMicroelectronics demoed this simple gesture control ...
Keysight shows you what signals lurk in real-time at 510MHz ...
TE Connectivity's clear-plastic, full-size model car shows ...
Why culture makes Linear Tech a winner.
Recently formed Architects of Modern Power consortium ...
Specially modified Corvette C7 Stingray responds to ex Indy ...
Avago’s ACPL-K30T is the first solid-state driver qualified ...
NXP launches its line of multi-gate, multifunction, ...
Doug Bailey, VP of marketing at Power Integrations, gives a ...
See how to ease software bring-up with DesignWare IP ...
DesignWare IP Prototyping Kits enable fast software ...
This video explores the LT3086, a new member of our LDO+ ...
In today’s modern electronic systems, the need for power ...