5 ms·

Bitter Lessons from the ISSpresso

136 points by zdw 5mo ago

pavel_lishin 5mo ago
The Pressurized Payloads Interface Requirements doc is kind of interesting. Lots of diagrams & such that would be great for art projects.
xoxxala 5mo ago
That was an excellent read for explaining why space isn’t just hard, but expensive.
- amelius 5mo ago
  It doesn't need to be, if you're okay with breaking things and moving fast.
  - shermantanktop 5mo ago
    And dying.
    - amelius 5mo ago
      Send robots. Also saves on espresso costs.
      - jojomodding 5mo ago
        But that's boring. Also it's already happening a lot more than humans are being sent.
sam1r 5mo ago
The flow diagram provided for fracture control is incredible. Quite a work of art. [1] [1] https://substackcdn.com/image/fetch/$s_!AOMG!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fd54b9b30-ccb2-4b40-8d3d-3a3149c52fa8_1864x1306.jpeg https://substackcdn.com/image/fetch/$s_!AOMG!,f_auto,q_auto:... Update: After staring at this flow diagram for quite some time, I realize it's actually the most robust, "complete-seeming" finite state machine I have seen used in the real world.
jacknews 5mo ago
Good read. "Since that time, I’ve learned that small heaters (like coffee makers or kettles) can be kryptonite to an inverter, and that this is common folk knowledge among solar installers." Is there any more on this? It can understand inductive loads maybe challenging inverters but resistive loads should be easy? Is it an issue of cheap inverter design, or something more fundamental?
- Fr0styMatt88 5mo ago
  From a quick Google that kinda makes sense, it’s just the strong, _sustained_ power draw that gives them issues. So I’d say fundamental AND inverter design — imagine pushing 2kW continuously through an inverter. It’s funny, power use can be really unintuitive. Try convincing someone that using the big air conditioner for heating is more efficient than using that little plug-in bar heater. Or yeah, a power board with 8 tiny wattage wall-warts isn’t using a lot of power. I could probably run my big fridge overnight off my portable battery generator, but it wouldn’t run my small electric kettle without putting it into a special mode and for nowhere near as long.
  - margalabargala 5mo ago
    That doesn't make sense to me. On a cheap RV inverter maybe, but on solar for a house? The inverters should be rated to continuously output whatever the panel is generating. It shouldn't care whether the 2kW is going back on the grid or into your water kettle, it should be doing that all day every day.
    - zhivota 5mo ago
      Typical hybrid inverters have an output rating around half the theoretical max input of the panels. This is due to theoretical max of panel input being very rare or even impossible in normal earth conditions, the presence of an attached battery to soak up part of the input, and the general cost benefit trade off of solar equipment (more throughput means more heat, means bigger heatsinks, means heavier and more expensive). You can definitely get equipment that can do symmetrical input/output, but if you actually model out the supply and demand curves on the system it's not usually going to be worth the extra up front expense since peak input is a small portion of the day and that extra hardware will mostly sit idle. For that matter people often design systems where peak input can't even be accepted by the inverter and the extra power is just wasted, because it's more valuable to have a steady input over a long period than to maximize the daily peak.
riffraff 5mo ago
I enjoyed reading this! But on one thing > You and I will probably die before we’re allowed to take a bottle of water through airport security again We could again bring water through airport security for some time in e.g. Rome's FCO (2 years maybe? It's been a while)
- tkocmathla 5mo ago
  At London Heathrow too, the 100ml limit was scrapped early this year. https://news.ycombinator.com/item?id=46736815 https://news.ycombinator.com/item?id=46736815
  - danielbln 5mo ago
    Same in Berlin, can now saunter through with liquids. Then there is Ben Gurion Airport TLV where you could always take liquids with.
    - FinnKuhn 5mo ago
      According to their website [1] only some scanners support the 2L limit while others don't so you will only know on arrival at the airport which limit is relevant for you. [1] https://ber.berlin-airport.de/en/flying/controls/security-control.html https://ber.berlin-airport.de/en/flying/controls/security-co...
- greatgib 5mo ago
  Do you know that for months we were able to bring water again in Europe airports? Thanks to an European regulation change that said that most scanners are now good enough and there is no need for this stupid rule. But then It was reverted because of US, for them it was unacceptable that we had that in Europe...
  - vrganj 5mo ago
    They hate us for our freedom.
  - 5mo ago
Panzerschrek 5mo ago
Why this ISSpresso machine was developed and sent into orbit at all? What scientific outcome does it have? Why was it necessary spending taxpayer's money developing it?
- spencer-p 5mo ago
  Astronauts can spend many months on the ISS, and it’s very important they don’t become irritable and kill one another before the research is complete.
  - danparsonson 5mo ago
    Also it's really hard to get up in the morning when the days are so short
- elromulous 5mo ago
  Are you sure Lavazza didn't eat the cost? It's great marketing material for them. This could be similar to the fisher space pen. There's a common urban legend that NASA spent millions developing the space pen, while the soviets simply used pencils. Fisher actually paid for the development of the space pen. https://en.wikipedia.org/wiki/Writing_in_space https://en.wikipedia.org/wiki/Writing_in_space
  - Leonard_of_Q 5mo ago
    As long as Lavazza also sponsors the launch costs for the coffee cartridges which come in at ~100 times the weight of the free-dried alternative used in lieu of this contraption. Next up: - the Russians will launch a new module containing a rye farm and a distillery 'cause cosmonauts can't be expected to drink pre-bagged vodka. - The Americans, not to be outdone launch a ring-shaped module containing a stretch of prairie where cattle roam 'cause damn'it we'll have our grass-fed beef whether we're in space or not. - When the Indians finally get their module attached it will turn out to be somewhat reminiscent of the American one with the addition of a ghee factory - the Japanese module is full of water and fish and space-sea-weed with a small compartment for the sushi chef - the Chinese module is filled with earth and eggs behind doors bearing labels telling the crew when the required 1000 years have been reached - the Dutch turn up with a giant solar wind mill - ...
deleted 5mo ago
[deleted]
picsao 5mo ago
[dead]
samuelec 5mo ago
Well, eventually it worked and astronauts can enjoy a good coffee :)

136 points by zdw 5mo ago

The Pressurized Payloads Interface Requirements doc is kind of interesting. Lots of diagrams & such that would be great for art projects.

xoxxala 5mo ago

That was an excellent read for explaining why space isn’t just hard, but expensive.

amelius 5mo ago
It doesn't need to be, if you're okay with breaking things and moving fast.
- shermantanktop 5mo ago
  And dying.
  - amelius 5mo ago
    Send robots. Also saves on espresso costs.
    - jojomodding 5mo ago
      But that's boring. Also it's already happening a lot more than humans are being sent.

sam1r 5mo ago

The flow diagram provided for fracture control is incredible. Quite a work of art. [1] [1] https://substackcdn.com/image/fetch/$s_!AOMG!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fd54b9b30-ccb2-4b40-8d3d-3a3149c52fa8_1864x1306.jpeg https://substackcdn.com/image/fetch/$s_!AOMG!,f_auto,q_auto:... Update: After staring at this flow diagram for quite some time, I realize it's actually the most robust, "complete-seeming" finite state machine I have seen used in the real world.

jacknews 5mo ago

Good read. "Since that time, I’ve learned that small heaters (like coffee makers or kettles) can be kryptonite to an inverter, and that this is common folk knowledge among solar installers." Is there any more on this? It can understand inductive loads maybe challenging inverters but resistive loads should be easy? Is it an issue of cheap inverter design, or something more fundamental?

Fr0styMatt88 5mo ago
From a quick Google that kinda makes sense, it’s just the strong, _sustained_ power draw that gives them issues. So I’d say fundamental AND inverter design — imagine pushing 2kW continuously through an inverter. It’s funny, power use can be really unintuitive. Try convincing someone that using the big air conditioner for heating is more efficient than using that little plug-in bar heater. Or yeah, a power board with 8 tiny wattage wall-warts isn’t using a lot of power. I could probably run my big fridge overnight off my portable battery generator, but it wouldn’t run my small electric kettle without putting it into a special mode and for nowhere near as long.
- margalabargala 5mo ago
  That doesn't make sense to me. On a cheap RV inverter maybe, but on solar for a house? The inverters should be rated to continuously output whatever the panel is generating. It shouldn't care whether the 2kW is going back on the grid or into your water kettle, it should be doing that all day every day.
  - zhivota 5mo ago
    Typical hybrid inverters have an output rating around half the theoretical max input of the panels. This is due to theoretical max of panel input being very rare or even impossible in normal earth conditions, the presence of an attached battery to soak up part of the input, and the general cost benefit trade off of solar equipment (more throughput means more heat, means bigger heatsinks, means heavier and more expensive). You can definitely get equipment that can do symmetrical input/output, but if you actually model out the supply and demand curves on the system it's not usually going to be worth the extra up front expense since peak input is a small portion of the day and that extra hardware will mostly sit idle. For that matter people often design systems where peak input can't even be accepted by the inverter and the extra power is just wasted, because it's more valuable to have a steady input over a long period than to maximize the daily peak.

riffraff 5mo ago

I enjoyed reading this! But on one thing > You and I will probably die before we’re allowed to take a bottle of water through airport security again We could again bring water through airport security for some time in e.g. Rome's FCO (2 years maybe? It's been a while)

tkocmathla 5mo ago
At London Heathrow too, the 100ml limit was scrapped early this year. https://news.ycombinator.com/item?id=46736815 https://news.ycombinator.com/item?id=46736815
- danielbln 5mo ago
  Same in Berlin, can now saunter through with liquids. Then there is Ben Gurion Airport TLV where you could always take liquids with.
  - FinnKuhn 5mo ago
    According to their website [1] only some scanners support the 2L limit while others don't so you will only know on arrival at the airport which limit is relevant for you. [1] https://ber.berlin-airport.de/en/flying/controls/security-control.html https://ber.berlin-airport.de/en/flying/controls/security-co...
greatgib 5mo ago
Do you know that for months we were able to bring water again in Europe airports? Thanks to an European regulation change that said that most scanners are now good enough and there is no need for this stupid rule. But then It was reverted because of US, for them it was unacceptable that we had that in Europe...
- vrganj 5mo ago
  They hate us for our freedom.
- 5mo ago

Panzerschrek 5mo ago

Why this ISSpresso machine was developed and sent into orbit at all? What scientific outcome does it have? Why was it necessary spending taxpayer's money developing it?

spencer-p 5mo ago
Astronauts can spend many months on the ISS, and it’s very important they don’t become irritable and kill one another before the research is complete.
- danparsonson 5mo ago
  Also it's really hard to get up in the morning when the days are so short
elromulous 5mo ago
Are you sure Lavazza didn't eat the cost? It's great marketing material for them. This could be similar to the fisher space pen. There's a common urban legend that NASA spent millions developing the space pen, while the soviets simply used pencils. Fisher actually paid for the development of the space pen. https://en.wikipedia.org/wiki/Writing_in_space https://en.wikipedia.org/wiki/Writing_in_space
- Leonard_of_Q 5mo ago
  As long as Lavazza also sponsors the launch costs for the coffee cartridges which come in at ~100 times the weight of the free-dried alternative used in lieu of this contraption. Next up: - the Russians will launch a new module containing a rye farm and a distillery 'cause cosmonauts can't be expected to drink pre-bagged vodka. - The Americans, not to be outdone launch a ring-shaped module containing a stretch of prairie where cattle roam 'cause damn'it we'll have our grass-fed beef whether we're in space or not. - When the Indians finally get their module attached it will turn out to be somewhat reminiscent of the American one with the addition of a ghee factory - the Japanese module is full of water and fish and space-sea-weed with a small compartment for the sushi chef - the Chinese module is filled with earth and eggs behind doors bearing labels telling the crew when the required 1000 years have been reached - the Dutch turn up with a giant solar wind mill - ...

deleted 5mo ago

[deleted]

picsao 5mo ago

[dead]

samuelec 5mo ago

Well, eventually it worked and astronauts can enjoy a good coffee :)