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My toddler loves planes, so I built her a radar

jacobbartlett.substack.com

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Re: My toddler loves planes, so I built her a radar

#221

Post by noir_lord »

blt wrote: post #116
ghewgill wrote: post #59

Earlier quoted context omitted.

They were vector displays. But possibly not quite in the way you're thinking. The original radar displays would scan from the center outward along a radial. The timing of the scan was predefined to scale for distance. The beam intensity signal was directly the (amplified) radar return signal. So a stronger returned signal would cause a more visible "blip" on the long-phosphor display. The interesting part is to make…

I was wondering about that after asking my question, since converting the signal to an x/y scope requires trigonometry. Probably a challenge to do electronically in the early days of radar. Leave it to the WW2-era engineers to find an electromechanical solution!

Radar was surprisingly advanced by the end of WW2, the Brits and Americans had ground scanning radar by the end of WW2 (H2S and the later H2X) all done without transistors or computers as we'd recognise them :).

Re: My toddler loves planes, so I built her a radar

#222

Post by cjrp »

oakmad wrote: post #43

This is great. On my « one day » build list. In a similar vein, my 5yr old son has a flight log book - I started it for him as a baby. Every flight he gives asks one of the crew if the captain wouldn’t mind completing it. It logs route, aircraft and any events that happened. The crew _love_ this kind of thing - we’ve toured cockpits and crew rests and the messages are always gracious. He’s always beaming to get it ba…

+1 on the logbook. We took my daughter London - New York when she was ~8 weeks old, and got some great photos from the cockpit, including her wearing the captain's hat.

Re: My toddler loves planes, so I built her a radar

#224

Post by jefftk »

d1sxeyes wrote: post #183
jefftk wrote: post #157

Earlier quoted context omitted.

On the other hand, if you want maximum realism, everything should fade continuously from when it is drawn. The underlying technology being imitated here is a slowly decaying phosphor.

Not sure if you picked up your own slight mistake earlier, but this is also exactly why you shouldn't try and 'tween' the planes to the new positions if you're aiming for realism.

Huh? What I'm proposing if you want to make it realistic (which may or may not be good UI) is:

* Everything fades from when it was drawn

* Everything is only drawn with the sweep

* Simulate a continuous motion for the planes, and use that to determine a new position at each sweep.

Did I make a mistake?

Re: My toddler loves planes, so I built her a radar

#226

Post by JKCalhoun »

Full_Clark wrote: post #131

Nice work and nice writeup. It's interesting to me how strongly the design of original radar displays anchors the project. Your toddler might never interact with a real CRT, much less an ASR-9 with a PPI display. But you've gone to great lengths to simulate one for her. Partly because of your affinity for skeumorphism, as you said, but it may also be because the OG radar display is a fantastic distillation of "Is the…

I like your comment — it points out that our RADAR displays were a both a product of the technology that was used to generate them (the sweep) but also that it was a deliberate way to make clear what it was you were observing (target distance was represented by distance from center, target bearing by angle around the circle).

To your point though, perhaps emulating the sweep was the questionable design decision — the bright colors, map-less background not controversial at all since they help focus on the intent of the display.

I did notice that as I turn with the phone, the compass-tracking feature broke the illusion of the sweep. :-)

Re: My toddler loves planes, so I built her a radar

#227

Post by footy »

hn_ta456 wrote: post #96

Love the design, but super uncomfortable with giving phones to toddlers as toys. For mine, the longer I can put it off the better. There are enough infants bumbling around the world already glued to screens, in imitation of their zombie parents (this is a general observation, not levelled at OP). For the inevitable “but kids need to learn how to use phones as tools” - tools for what? They are designed to consume you…

Is that really what's happening here though? Seems like the author is using the app with their toddler, and it's only a tool to do something in the real world.

Kind of made me think of my dad teaching me to use a compass or looking at star charts with me in the early 90s.

Re: My toddler loves planes, so I built her a radar

#228

Post by pcardoso »

alberto_ol wrote: post #202
jakey_bakey wrote: post #48

Earlier quoted context omitted.

That's genius, being invited into the cockpit felt extremely cool even as a grown adult, so I will absolutely get this started next time we get a flight

I thought that after 9/11 passengers were not allowed to visit the cockopit any more

perhaps, but my 10yo son was invited to land in the cockpit earlier this year. he loved it and will never forget it.

(domestic flight, Europe)

Re: My toddler loves planes, so I built her a radar

#230

Post by seanc »

JKCalhoun wrote: post #226
Full_Clark wrote: post #131

Nice work and nice writeup. It's interesting to me how strongly the design of original radar displays anchors the project. Your toddler might never interact with a real CRT, much less an ASR-9 with a PPI display. But you've gone to great lengths to simulate one for her. Partly because of your affinity for skeumorphism, as you said, but it may also be because the OG radar display is a fantastic distillation of "Is the…

I like your comment — it points out that our RADAR displays were a both a product of the technology that was used to generate them (the sweep) but also that it was a deliberate way to make clear what it was you were observing (target distance was represented by distance from center, target bearing by angle around the circle). To your point though, perhaps emulating the sweep was the questionable design decision — the…

Now I have a funny vision in my head of a WWII radio tech standing in a field, wearing an absurdly large RADAR rig, with a big sweeping antenna protruding from a backpack and a massive screen on his chest, turning this way and that, all confused by how the sweep doesn't look quite right...
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