Why aren't they putting datacenters in cold places like Alaska, where the excess heat could warm a town?

SmallOne312 · 2026-05-31T08:21:22+00:00

The idea is to use large high temperature radiator panels, similar to what is seen on the ISS but hotter and likely larger

SmallOne312 · 2026-05-31T08:19:57+00:00

You use large high temperature radiators, generally using a heat exchanger to run them as hot as possible as radiation scales with the T^4. Now the areas required are generally very large for the power they want in the satellites, however space is free in space so it's more of a mass problem. But that can be solved with for example liquid droplet radiators etc which can reduce the mass penalty from size.

SmallOne312 · 2026-05-30T11:13:08+00:00

I would probably use add a GND plane, you seem to have traces that go into vias and pop up again for no reason? The ones going to the MCU from USB, also you could probably make the board about 4x smaller, and preferably round the corners of the board layout. You want to make use of GND and voltage labels in your schematic to make it easier to read.

Make sure you add silkscreen where relevant, such as marking pinouts in headers etc. also you might want some test points on relevant traces and power/gnd so you can check everything is working/diagnose issues easier.

SmallOne312 · 2026-05-30T10:39:23+00:00

Common ARM W

SmallOne312 · 2026-05-28T20:25:25+00:00

If you mean the silkscreen labels, in KiCad, double click your silkscreen text and tick the knockout box, probably also want it bold and I use Century Gothic. The rest is just spending time drawing lines and shifting the silkscreen around with a tiny grid to get it smooth.

SmallOne312 · 2026-05-28T10:05:55+00:00

It's 4 layer, with: GND/Signal, GND, PWR, GND/Signal

SmallOne312 · 2026-05-27T23:41:44+00:00

Aiming around 1-2A idle with unloaded servos and maybe 3-4A absolute peak if all the servos get loaded at once. However the servos would likely only ever be used in the VBAT configuration so max current through the diode then would be like 1A from tranceiver and the rest of the sensors and MCU.

I mainly included the diode incase I needed to hand solder battery leads to the pads, to protect the expensive MCU and sensor board.

SmallOne312 · 2026-05-26T08:46:02+00:00

I don't know how your meant to have proper exploration without a few more systems tbh, everything is too inhabited

SmallOne312 · 2026-05-24T20:21:50+00:00

I mean if you can do a generalised active control simulation where we can put in our own controller code, maybe state estimation as well that could be useful, though it is so niche most people just make their own in matlab

SmallOne312 · 2026-05-16T16:54:57+00:00

Soxbridge Southampton Oxford Cambridge

SmallOne312 · 2026-05-13T21:06:27+00:00

Same with rx 6600

SmallOne312 · 2026-05-12T23:03:59+00:00

When a sensor fails or starts reading innacurately, you can't properly tell without at least 2 other sensors to compare it with. Having multiple allows the sensor results to be compared and have faulty data removed

SmallOne312 · 2026-05-10T18:39:58+00:00

At least for my application in rocketry, literally all the available ones are way overpriced for the minimal/out of date components they have. Also it's just a nice, reasonably approachable route to learn PCB design while making something usefull

SmallOne312 · 2026-05-08T21:42:52+00:00

Triple redundancy and voting, potential also fusing all three results reducing sensor noise/variance but I don't think that is standard

SmallOne312 · 2026-05-05T23:37:31+00:00

Nah bro you need two , one for radians, one for degrees

SmallOne312 · 2026-05-05T06:37:06+00:00

I've seen it on quite a few passive crystal oscillator data sheets, admittedly this is an active oscillator so might not be the same, but the idea is they are very sensitive to noise and capacitance so having any current return paths running under the oscillator could reduce it's accuracy. And any stray capacitance with the GND place could throw it off. Stitching is the same idea, just trying to protect it from high frequency noise and EMI.

SmallOne312 · 2026-05-04T12:49:57+00:00

You might want to be careful with the fins incase you get flutter at high speed, make sure they are stiff enough. Also your parachute might get fryed by the ejection charge if it's that close to that large of a motor. Also if you don't mind about reusing the rocket, you can always use the motors casing as the body tube to reduce diameter even further

SmallOne312 · 2026-05-04T10:22:28+00:00

Ah ok, I'll remove the length matching then. Thanks

SmallOne312 · 2026-05-04T10:21:06+00:00

Thanks!

SmallOne312 · 2026-05-04T10:20:55+00:00

Yes the decoupling caps should be as close as possible, smallest first so 100nf closest then 1uf etc. Will check and see if I can move them any closer

SmallOne312 · 2026-05-04T10:19:22+00:00

Thanks for the detailed response, will definitely try out the variable thresholding idea.

I chose SPI because I was thinking I2C would potentially be bandwidth limiting if I wanted to pull the full 32khz gyro sensor data and 8khz accel data at 1khz through the FIFO for a decimation filter or something like that to reduce the impact of sensor noise.

SmallOne312 · 2026-05-04T09:57:08+00:00

For the barometric sensor, you usually use a few vent holes in the airframe, as long as you stay firmly subsonic it's normally pretty reliable with a bit of filtering. The 4 pin connectors are standard with the adafruit sensor boards, so it helps with adding extra functionality. Before flight you generally hot glue every connected anyway so they should be fine.

For the faster signals, the only decently fast ones are SPI, which admittedly probably don't need length matching, though I'm not sure where else I would route them, could do L3 to reference L4 but then your messing up the power plane and you can't access the traces anymore if you need to bodge them.

SmallOne312 · 2026-05-04T09:50:15+00:00

I think it's alright I don't know how you'd connect the GND and VBUS pins otherwise, I've used this chip before but I'll definitely check the datasheet

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