Author Topic: LightSail / Planetary Society build a $2.5M+ satellite with no watchdog timer  (Read 8785 times)

0 Members and 1 Guest are viewing this topic.

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us
http://sail.planetary.org/missioncontrol

http://sail.planetary.org/story-part-1.html

In short, Bill Nye is attempting to wear the mantle of Carl Sagan by realizing Sagan's vision of a spacecraft propelled by light pressure.  It is a program that has resulted in a spending spree that would even make NASA blush.  Over $4M in donations have been expended thus far on two, 3U Cube Sats.  One cube sat is currently drifting about the earth incommunicado, CPU locked up due an easily reproducible software error.  Apparently, in the melee to spend millions on cube sats (the raw kits cost maybe $10K each), they forgot to include an external watchdog timer.  In fact, the Planetary Society seems blissfully unaware of such a device's existence.  From:http://www.planetary.org/blogs/jason-davis/2015/20150526-software-glitch-pauses-ls-test.html?referrer=http://t.co/iEqtb4yZvL

Quote
When I filmed an interview with our CEO, Bill Nye, and system engineer Barbara Plante, last year, Nye points out a piece of hardware strapped to BenchSat, LightSail’s acrylic-mounted testing clone:

“There’s nobody in outer space to push that reset button,” says Nye.

The Planetary Society's current plan is to await a perfectly-timed cosmic ray to reset the CPU, then fix the bad firmware that should have been tested on Earth (had the Planetary Society had the foresight to perform systems tests prior to launch).

Cube Sats are not cheap, but they don't cost millions each either.  Launch costs are listed between $50K and 100K USD - which I'm assuming is for a 1U.  If there are reaction wheels, sun and or star trackers, etc., that adds to the cost as well.  And of course engineers and techs cost money, but $5.5M is a staggering sum for what are largely existing plaftorms with an add-on "pop-up" sail.

Now, thanks to the miracle of crowd-funding, you too can help the Planetary Society spread the word about questionable engineering and test practices by giving them more cash to blow via Kickstarter:
https://www.kickstarter.com/projects/theplanetarysociety/lightsail-a-revolutionary-solar-sailing-spacecraft
 

Offline bills

  • Frequent Contributor
  • **
  • Posts: 350
  • Country: us
I informed them about your idea of a external watchdog timer, maybe they will learn something.
 
Never argue with idiots. They drag you down to their level and beat you with experience.
 

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us
I alluded to the file overflow problem, which should have easily been detected. I'm talking about an external watchdog doing a system reset including the radio, not the watchdog internal to the micro. Regardless of the specifics, I'm shocked at the level of spending versus the obvious lack of testing and design.

This has been a huge drain on the finances of the Planetary Society. I thought the $4M might have been an exaggeration, but nope.  A perusal of the annual reports shows they really did spend it, or at least allocated it to that accounting bucket.
 

Offline Mechanical Menace

  • Super Contributor
  • ***
  • Posts: 1288
  • Country: gb
This has been a huge drain on the finances of the Planetary Society. I thought the $4M might have been an exaggeration, but nope.  A perusal of the annual reports shows they really did spend it, or at least allocated it to that accounting bucket.

That's bloody cheap for three missions, and believe it or not they may have decided not to include something like an external watchdog timer due to the weight, every gram counts on launches. And it could have been worse, they could have mixed up inches and centimeter, but I guess no one spending millions would ever do that :p
Second sexiest ugly bloke on the forum.
"Don't believe every quote you read on the internet, because I totally didn't say that."
~Albert Einstein
 

Offline andersm

  • Super Contributor
  • ***
  • Posts: 1198
  • Country: fi
In one of the comments on the blog post, it was mentioned that the system board was designed by a company called Tyvak. Assuming it is this one, there is an external hardware watchdog present. That would mean it is either not used, or it is never triggered due to some design flaw in how the software tasks are monitored.

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us
This has been a huge drain on the finances of the Planetary Society. I thought the $4M might have been an exaggeration, but nope.  A perusal of the annual reports shows they really did spend it, or at least allocated it to that accounting bucket.

That's bloody cheap for three missions, and believe it or not they may have decided not to include something like an external watchdog timer due to the weight, every gram counts on launches. And it could have been worse, they could have mixed up inches and centimeter, but I guess no one spending millions would ever do that :p

Cheap for big space for sure.  For microsats, not so much.  AMSAT (who probably has launched more microsats than any other single entity) estimates launch costs at $100K USD/kg. So, I could see a $250K launch bill x 3.  Maybe tracking station time is more expensive than I think it is.  But over $5M for three microsats really seems expensive.

 For reference, a 16 pin DIP package is approximately 0.001661 kg.  So, we're talking about a sub-$300 decision with solder and support components.  Not cheap, but reasonable insurance in light of the launch costs.

Regardless, testing adds no weight at all.

The good part of all this is that it has me reading up on microsats and might get inspired to get my HAM license and join AMSAT.  Those folks really have cost-effective space nailed down. 
 

Offline m98

  • Frequent Contributor
  • **
  • Posts: 613
  • Country: de
That's bloody cheap for three missions, and believe it or not they may have decided not to include something like an external watchdog timer due to the weight, every gram counts on launches. And it could have been worse, they could have mixed up inches and centimeter, but I guess no one spending millions would ever do that :p
A simple watchdog timer IC as CSP weights somewhere in the milligram region, launch costs are not nearly calculated that tight.
 

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us
In one of the comments on the blog post, it was mentioned that the system board was designed by a company called Tyvak. Assuming it is this one, there is an external hardware watchdog present. That would mean it is either not used, or it is never triggered due to some design flaw in how the software tasks are monitored.

Interesting.  Here's the price sheet:  http://static1.squarespace.com/static/50e0b24de4b03955129ee278/t/53dfc347e4b07b43013d5d20/1407173447631/BB14-70_Tyvak-IntrepidDatasheet4.pdf

I'm coming up with $56,500 for a fully-optioned out 3U system with integration.  So, $169,500 for 3 satellites in basic hardware costs + the sail system + launch costs + ground control.

Basic mass is 1.2kg, call it 2kg with the sail, so $200,000 each in launch costs. I'm up to $870,000. 

So, let's round up and call this program a $1.5M program for three satellites, launch costs, ground costs, NRE and extra hardware for the sails. 

Where's the other $3M+?  What have I left out?

 

Offline bills

  • Frequent Contributor
  • **
  • Posts: 350
  • Country: us
« Last Edit: June 09, 2015, 11:56:01 pm by bills »
Never argue with idiots. They drag you down to their level and beat you with experience.
 

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us
It's working again. It appears a cosmic particle rebooted it???
http://www.planetary.org/blogs/jason-davis/2015/20150607-lightsail-deployment-initiatied.html

The Planetary Planetary Society has a curious definition of "success:" bad firmware undiscovered due to not allowing the unit to operate for over 40 hours prior to launch (who does that!?), a bad power system, and a partial sail deployment. I'd be ok with "we've got some work to do," but to do a victory lap after screwing the pooch so badly is just absurd.
 

Offline Len

  • Frequent Contributor
  • **
  • Posts: 547
  • Country: ca
The Planetary Planetary Society has a curious definition of "success:"
Standard procedure, re-define "success" after the mission. Look at NASA's press release about the failed LDSD test the other day:
http://www.nasa.gov/press-release/nasas-ldsd-project-completes-second-experimental-test-flight
For the second time, the parachute ripped when it was deployed. But now they say that's what they wanted to happen:
Quote
"Going into this year's flight, I wanted to see that the parachute opened further than it did last year before it began to rupture."
Yeah, right.
DIY Eurorack Synth: https://lenp.net/synth/
 

Offline Howardlong

  • Super Contributor
  • ***
  • Posts: 5315
  • Country: gb

Where's the other $3M+?  What have I left out?

I suspect because a good deal of the development was farmed out commercially, but will ask those in the know.

AMSAT organisations, of which I am an active member and am involved directly in many past and present spacecraft development projects, both successful and a few not quite so much, are predominantly run and developed by volunteers. We do sometimes use third party off the shelf parts such as deployable antennas and power supplies where we sometimes find we lack sufficient resource, but from a pure R&D and testing perspective it's pretty much all volunteer work.
 

Offline LabSpokaneTopic starter

  • Super Contributor
  • ***
  • Posts: 1899
  • Country: us

Where's the other $3M+?  What have I left out?

I suspect because a good deal of the development was farmed out commercially, but will ask those in the know.

I think it's these folks:  http://www.eclipticenterprises.com/
 

Offline Rasz

  • Super Contributor
  • ***
  • Posts: 2616
  • Country: 00
    • My random blog.
Where's the other $3M+?  What have I left out?

middlemen, telephone sanitizers gotta eat
Who logs in to gdm? Not I, said the duck.
My fireplace is on fire, but in all the wrong places.
 

Offline Stonent

  • Super Contributor
  • ***
  • Posts: 3824
  • Country: us
Where's the other $3M+?  What have I left out?

middlemen, telephone sanitizers gotta eat

The larger the government, the smaller the citizen.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf