4 ms·

Does anybody know what the intended use of these "non explosive actuator"s were? Are they resettable? Does using them for freeing the antenna degrade another pa

Does anybody know what the intended use of these "non explosive actuator"s were? Are they resettable? Does using them for freeing the antenna degrade another part of the mission?

cwillu 3y ago
I _think_ they're often nitinol, i.e., shape-memory metal. Nitinol can be hot-formed, cooled, then formed a further limited amount. When reheated, they will return to their hot-formed shape.
- somat 3y ago
  I don't think a shape memory alloy would provide a shock. I suspect they are solenoids(vs explosive bolts) used to detach the vehicle from it's mounting plate on the rocket. and the engineers as they went down the list trying increasingly wild ideas to get the antenna to deploy reached "fire the release solenoids, and hope it shakes the antenna pin in the correct way". It did, so slow clap for the engineers for saving a very expensive science experiment remotely from billions of miles away. well done.
  - morelisp 3y ago
    "Slow clap" likely doesn't have the connotation you want...
    - djmips 3y ago
      There is that charming eighties movie 'slow clap' that builds to a crescendo of appreciation and/or support.
    - abudabi123 3y ago
      The French fans of American MMA express their appreciation with golf or tennis claps. A contrast in technique and style between American and French MMA is seen in the Jon Jones vs Cyril Gane heavy weight fight. Back on topic, the release mechanism jams every now and again across the probes sent to deep space. Hope the engineers are given the window of opportunity to solve this category of problem once and for all by business-ops. The release of the JWST antenna while at the moment of sparkly reflections in the sunshine looked real strong.
  - moffkalast 3y ago
    ESA going for the old reliable percussive maintenance procedure.
    - dylan604 3y ago
      I'm envisioning a large cartoonish sledge with the letters ACME stamped on it
  - onetwentythree 3y ago
    The shock typically comes from the release of the preload, not from the NEA itself.
- marsokod 3y ago
  Or it could be a PCM pin-puller system: basically paraffin is heated and while it liquifies, it will slightly expand and push a pin that will trigger the release.
deleted 3y ago
[deleted]
serf 3y ago
there are lots of different kinds of NEAs. https://cms.nacsemi.com/Images/FeaturedProducts/Eaton_Non-Explosive%20Actuators.pdf https://cms.nacsemi.com/Images/FeaturedProducts/Eaton_Non-Ex...
- amelius 3y ago
  Isn't just about any actuator of the "non-explosive" kind? I mean, the motor in my DVD drive tray is a non-explosive actuator I suppose.
  - jakeinspace 3y ago
    Well, at least under nominal supply voltage.

Does anybody know what the intended use of these "non explosive actuator"s were? Are they resettable? Does using them for freeing the antenna degrade another part of the mission?

cwillu 3y ago

I _think_ they're often nitinol, i.e., shape-memory metal. Nitinol can be hot-formed, cooled, then formed a further limited amount. When reheated, they will return to their hot-formed shape.

somat 3y ago
I don't think a shape memory alloy would provide a shock. I suspect they are solenoids(vs explosive bolts) used to detach the vehicle from it's mounting plate on the rocket. and the engineers as they went down the list trying increasingly wild ideas to get the antenna to deploy reached "fire the release solenoids, and hope it shakes the antenna pin in the correct way". It did, so slow clap for the engineers for saving a very expensive science experiment remotely from billions of miles away. well done.
- morelisp 3y ago
  "Slow clap" likely doesn't have the connotation you want...
  - djmips 3y ago
    There is that charming eighties movie 'slow clap' that builds to a crescendo of appreciation and/or support.
  - abudabi123 3y ago
    The French fans of American MMA express their appreciation with golf or tennis claps. A contrast in technique and style between American and French MMA is seen in the Jon Jones vs Cyril Gane heavy weight fight. Back on topic, the release mechanism jams every now and again across the probes sent to deep space. Hope the engineers are given the window of opportunity to solve this category of problem once and for all by business-ops. The release of the JWST antenna while at the moment of sparkly reflections in the sunshine looked real strong.
- moffkalast 3y ago
  ESA going for the old reliable percussive maintenance procedure.
  - dylan604 3y ago
    I'm envisioning a large cartoonish sledge with the letters ACME stamped on it
- onetwentythree 3y ago
  The shock typically comes from the release of the preload, not from the NEA itself.
marsokod 3y ago
Or it could be a PCM pin-puller system: basically paraffin is heated and while it liquifies, it will slightly expand and push a pin that will trigger the release.

deleted 3y ago

[deleted]

serf 3y ago

there are lots of different kinds of NEAs. https://cms.nacsemi.com/Images/FeaturedProducts/Eaton_Non-Explosive%20Actuators.pdf https://cms.nacsemi.com/Images/FeaturedProducts/Eaton_Non-Ex...

amelius 3y ago
Isn't just about any actuator of the "non-explosive" kind? I mean, the motor in my DVD drive tray is a non-explosive actuator I suppose.
- jakeinspace 3y ago
  Well, at least under nominal supply voltage.