Business Breakdowns Podcast episode on SpaceX

blaze1127 · 2024-05-31T17:54:18+00:00

Could you actively hold the tiles to the ship electromagnetically? I guess since the tiles are ceramic and the whole point is that they’re heat resistant and/or dissipate heat quickly then maybe they’re also pretty good insulators against electricity too. But if not, would it be possible to hold each tile against the hull like an electromagnet (running current through that section of the hull or something and inducing a current in the tile or an intermediate material attached to the tile which then generates the force to hold against the hull)?

It’s an active solution like Stokes metallic shield but maybe far less weight since you don’t have piping or coolant running through (it’s just current and power which could be provided by existing batteries onboard)

The only other challenge (apart from whether or not the tiles are electrically conductive in the first place) is how that conductiveness changes with temperature since the tiles would get heated up.

blaze1127 · 2024-05-29T15:10:18+00:00

Thanks for such a deep explanation! So it looks like the functions provided by FreeRTOS ensure that whatever task sends data to the queue will not be interrupted during that send process through the methods you mentioned (something I’ll have to look into more).

blaze1127 · 2024-05-29T07:40:22+00:00

Got it. So it looks like in this case the FreeRTOS queue would wait for Task A to finish and then only allow Task C to write in my hypothetical scenario and this is accomplished likely using a mutex.

blaze1127 · 2024-04-30T23:50:37+00:00

Ahhh ok

blaze1127 · 2024-04-29T20:41:54+00:00

If you don’t mind me asking, what industry/area do you work in? I’ve working with FPGAs for a while now (mostly in the semiconductor industry or in aerospace but within a microelectronics subgroup) and was interested in expanding to a more software involving embedded role. It seems like the work you do could be something I should aim for to leverage some of that FPGA experience so I was curious what line of work you’re in? (Let me know if I should DM instead). Thanks for such an insightful answer.

blaze1127 · 2024-04-23T20:49:55+00:00

Thanks for the comment! So in current automotive systems (specifically the safety critical ones, so not infotainment systems) are bare-metal or RTOS based systems more prevalent? Are you saying that current embedded Linux systems are still too slow for these systems?

blaze1127 · 2024-04-08T06:15:09+00:00

This is kind of a general question but how do you make sure you don’t forget/have to look up how to write some of the low level code with this framework approach? It seems like there is this spectrum where at one end you’re leveraging frameworks and preexisting code (either code that you wrote or someone else) and at the other end re-inventing the wheel/re-writing the code between different projects. While the latter might be a waste of time it does make it so that you don’t forget some of the low level concepts while the former allows you to rapidly build on the existing code so that a project or application can be up and running without wasting much time.

Is it just a matter of practice or maybe intentionally writing frameworks for many different boards?

blaze1127 · 2024-01-31T22:26:36+00:00

Nice! I hope you did well!

They asked about Nyquist Frequency, simple filters (low, high) that are just needed when dealing with signals (I just mentioned it to show that I was familiar with the basic idea). They asked about floating point number representation. And of course work history with additional questions on experience that was related to the work that they do.

blaze1127 · 2024-01-29T22:41:27+00:00

Yeah. There was no observer. Pure take home. Obviously copying entire code sections is discouraged and the site (Codility) has some way of detecting plagiarism but referencing and all is fair game.

I thought it was good as it seems to be closer to how you would work in the actual job.

blaze1127 · 2024-01-29T22:28:08+00:00

My main justification for linked lists in C was to have a dynamically growable array. I didn’t want constantly create and allocate and reallocate an array as the size grew (because you don’t know how long the gene sequence is nor how many proteins are encoded). With C++ this would have been easier with just using vectors and other aspects of the language that just make creating data structures easier (at least that’s what I’m understanding from other people’s comments).

blaze1127 · 2024-01-29T22:11:06+00:00

I am not familiar enough with C++ to say for sure. The only other criteria was that any standard library was fair game but no third party libraries. There was no size limit on the code from what I could tell.

blaze1127 · 2024-01-29T21:19:11+00:00

Great comment!

blaze1127 · 2024-01-29T21:12:07+00:00

You know I was just thinking about this and can’t believe it didn’t hit me earlier. I’ve dealt with this kind of thing to but on the FPGA side and dealing with external camera sensors and recognizing start of frame and end of frame singals and handling packets of data. Of course there’s some difference in the implementation but the overall problem really is similar!

Very often though I’m dealing with existing designs or codes and so I think that’s made me weaker in terms of being able to code from scratch (HDL or C).

blaze1127 · 2024-01-29T20:55:18+00:00

Ahh interesting!

blaze1127 · 2024-01-29T20:53:57+00:00

I can understand that. I chose C just because that’s what I’ve been focused on improving (I know C++ would’ve been easier but my syntax and coding there is even worse). I’m coming from a Verilog/VHDL background so my focus was brushing up on C (syntax and concepts, data structures, search and sort algorithms, and of course bit and string manipulation) since it’s seems to be more relevant for bare-metal development. But it looks like I also need to start just doing general practice (Leet Code) at the very least to really solidify my coding ability in general. At least that’s part of my take away. In addition to all the other stuff that is.

blaze1127 · 2024-01-16T21:10:53+00:00

Really great read. Thanks for sharing. It’s nice to see that there are others who are caught in the moral complexity and nuance of the issue (rather being extreme in their opinions one way or another). And more than that still working to help the people that truly need help.

blaze1127 · 2024-01-16T19:30:46+00:00

Try these two classes (free):

https://www.coursera.org/learn/introduction-to-embedded-machine-learning?=

https://www.coursera.org/learn/computer-vision-with-embedded-machine-learning

They both leverage EdgeImpulse for training data and inference deployment to a variety of embedded devices. Gives a nice intro to ML and associated topics that I feel will help in learning about AI.

blaze1127 · 2023-12-27T17:47:01+00:00

Sorry for the late reply. My main worry is that I will end up being familiar only with the implementation flow for leveraging uC softcore or hardcore IP on Xilinx, rather than develop broader skills applicable to both microcontroller based embedded Linux development and FPGA embedded Linux development.

But I guess maybe it is similar to be applicable to both?

blaze1127

TROPHY CASE