289Views76Replies

Author Options:

Solid State Sensors? (Very Edited) Answered

What properties of an environment can be measured with solid state sensors? Specifically, I am thinking of a project requiring a suite of sensors-on-chips that can measure their immediate (dry) environment and pass the data to a control unit.

So far, I know of temperature, magnetism, radiation, acceleration and light (a camera chip).

Are there any other (reasonably priced) solid state sensors, and where could I find them (either new, or reclaimed from something else)

Edited:

OK, so I thought I could be vague about my questions and then surprise everybody with a working satellite.

Turns out I'm not so clever as I thought.

I'm trying to recreate Sputnik on a tiny budget. Something that could be made by Joe Public, without having to rely on grants or Lottery funding.

Sputnik weighed nearly as much as I do, but all it did was measure temperature and pressure, then send beeps that changed if the temperature or pressure went outside a certain range. I know it has been outdone by students with CubeSats, but they still cost tens of thousands of dollars.

I thought that it should be possible to recreate (and out-do) Sputnik's capabilities on a single board, a simple programmable control chip taking in the data from a set of sensor-chips encoding it somehow, then passing it to a transmitter to be beamed to Earth.

I thought - still thinking micro-budget - that the whole thing could be cased in a short piece of sealed PVC tubing, since PVC is radio-transparent.

In my head, in fact, the satellite looks like a relay baton, but shorter.

Am I being stupidly optimistic?

Discussions

Sounds cool, but you'd also need a heckuva powerful antenna to transmit from low orbit. With antennas comes batteries, and before you know it, the whole satellite is too heavy to lift with weather ballons... You'd require a lot of R&D to get this done. You don't have to clear it with NASA, do you?

He's British. He wouldn't have to clear it with NASA in any event.

Ah yes, my mistake. You seem to be correcting my a lot lately...

Hey, find your own stalker, Adrian is mine!

Go ahead, you can have her. I'll take bumpus and we'll call it a day.

NO! This is the first time I've spoken to Firebert! EVER!

Oh, it's all right. No need to be sorry, Goodhart.

Actually, it was pretty funny. :)

You mean, "correcting ME a lot lately"? :)

Actually, I don't know what you mean...

How ironic that my last post happened to have a typo that you corrected.

I usually have flawless grammar.

As for correcting me, you have sorta been jumping all over me if I happen to be incorrect. I can't be bothered to go dig up evidence right now, but it's there.

It's not a big deal, maybe we can pretend it never happened.

>As for correcting me, you have sorta been jumping all over me if I happen to be incorrect. I can't be bothered to go dig up evidence right now, but it's there.

You must have me confused with someone else. To the best of my knowledge, I have never spoken to you before this. And certainly never corrected you. I promise.

I am sorry I upset you by correcting you on this-I had no idea it would. And I really don't care about typos like that-I just thought it was highly ironic, too. :)

I hope we can move past this.

I wouldn't think so, maybe the British National Space Centre ?

I doubt it. Space agencies don't exactly put a number on a billboard saying "call this number first if you plan to launch something"...

I haven't a clue.....just knew of their existence and made the suggestion :-) Hmmm, so building and launching rockets in the UK is kind of ignored then?

the Antenna is "sized" according to wavelength, the "transmitter" may need to be pretty powerful, but it is amazing how far a 5 watt signal can travel at the proper frequency. :-)

How exactly do you plan to work the "Control box"? What are you going to base it on?

I have no idea, yet.

I have a rather vague plan to build a DIY satellite, as a sort of homage to Sputnik. I've seen the capability recreated in a "CubeSat", but they typically cost thousands to build, since you've got to meet NASA bureaucracy redtape all the way through the build.

I have this very vague plan to recruit other people near me over the next couple of years. I'm thinking of when I start working at High School in a couple of years, get some staff and sixth-formers together, try and get a nano-sat off the ground (literally, although it might be by balloon).

Yeah - I'd think getting that thing into orbit would be your main challenge. Do you already have an idea for that (e.g., you stockpile rocket fuel in your shed)?

Possibly a really large catapult? Financially, the most realistic option is probably a weather balloon - that's edge-of-space, missions will last days, and the gear can be recovered by parachute (so it could also record data for later download, and also be re-used). Dreaming, though, I wonder if we could persuade Richard Branson to strap one to the outside of SpaceShipTwo?

Are you serious about the catapult? I don't think so, but you never know with Kiteman...
The weather balloon thing sounds great! What is the ultimate goal -- to put it into orbit like Sputnik? Or collect more data on a smaller budget? The weather balloon idea wouldn't put it into orbit, would it? Maybe you could attach rockets to the device to put it into orbit right after getting to its apex in the balloon.

Serious about the catapult? Goodness me, no!

Weather balloons get close to orbital heights, for a tiny fraction of the cost (a few hundred pounds instead of hundreds of thousands). Somebody was working on the rocket-from-a-balloon plan, I dont think they have got it working yet.

thought so, now I feel silly for even raising an eyebrow.
Yeah, launching from a high-up balloon would be problematic, mostly because you don't have good, solid ground to give stability and push against for lift-off. Plus, to go up would require going through the balloon... Unless you have multiple balloons with an area of space around them... (five minutes later, from Paint.exe) Like this!

Kiteman's balloons.JPG

. A rocket doesn't push against the ground. Well, it does, but that doesn't add any lift. It's throwing a lot of mass out the back and using "for every action, there is an equal and opposite reaction."

I think what I was really trying to talk about was the stability of the ground, as opposed to waving around in the upper atmosphere, swinging from a balloon...

in other words, whereas most rockets fired from the ground are guided for a few feet to a few hundred feet by a guide of some sort, and have a stable trajectory, one in a balloon might not have the stability, especually if it is high enough to encounter high winds.

Also, the lack of atmosphere that high up would render aerodynamic stabilizers useless... If there were another method, the basket/balloons approach would be extremely feasible.

Also, the lack of atmosphere that high up would render aerodynamic stabilizers useless...

At "startup" speeds, yes, I agree.

Heh. I remember reading a really funny analogy somewhere-that a rocket's propulsion is just like a guy throwing rocks out the back, only faster.

(That's a bird's-eye view, BTW.) You could have the gunpowder staged, or perhaps mixed with a mild retardant (giving us a boost instead of KABOOM). Have the whole thing conical in shape, to motivate its drag toward earth, as well as to channel the force of the burning gunpowder in one direction. A set of channeling vanes could be placed inside the rocket to add stability. Wires could run through the vanes to allow wired-wireless ignition (user on ground > control/sensor box > igniter). And I just realized, the payload could be sitting on a basket giving it nearly the same stability as the ground! As for materials to encase everything, well... I failed the egg drop challenge both times I had it in school...

Kiteman's payload.JPG

Why not try the oldfashioned standby for launching things very high up-gunpowder? Yes, many things could go wrong, the payload could be destroyed, you could lose an arm, you could be killed or catastrophically injured, you could get arrested, fined and put into jail...hmmm, maybe not...

Good idea! Actually, gunpowder would be a very viable option if it were mixed with retardants -- playing it safe, as it were. It would burn more slowly and reliably.
And I'm sure it's easy to stay out of jail using one out of three ways:
1) be sneaky so nobody knows (yeah, right)
2) befriend the mayor!
3) honestly seek a permit for what you're doing, it's not that hard. Depending on what you want to label your activities as. I find that being up-front really gets you places -- people like honesty. And hey, this is Kiteman we're talking about! Science teachers are supposed to blow things into the exosphere!

>Good idea! Thank you! :) I bet Kiteman will find a way to make this happen. And get on international TV...

recently I've been considering a massive catapult for other purposes it's not completely out of reason, in terms of launch prices you could knock them down by a few million pounds even for constructing it for one launch... To fund the project things like this could be sent in to space afterwards as a business, if it was powerful enough to break orbit then there'd be a lot of opportunities...

Possibly a really large catapult?

Where's Trebuchet when you need him :-)

I see. Probably best to start small with something like data loggers attached to a kite to measure windspeed/temperature and see where it goes from there.

...attached to a kite...
Now that's tooting your own horn!

Hmm, the anchoring cord would become a problem though....I have had kites I have flown up high enough to not be able to see them except for a tiny dot in the sky. The cord needed to hold it and still not break, arched upwards after nearly paralleling the ground for a couple of hundred feet. It took hours to get the thing reeled back in by hand *sigh* the good ole days.

Twas a lot of "line" too :-) I was always afraid it might come crashing down across power lines or something

Oh! What about PongSat??'''

The project has to fit inside a pingpong ball, and is free to launch!

That appears just to be weather-ballooning... I think you'd be better off DIY'ing it.

0
None
iman

9 years ago

have you checked out ahab?

Kiteman seems pretty excited. What does Kitewife think of all this? Another big waste of money maybe.

She's quite approving of the PongSat idea, since I might be able to get my school to pay for part or all of it.

Nah, she's proud to have a husband who's interested in rebuilding sputnik instead of watching TV and guzzling beer.