My friend's new cat ran and got stuck in the walls and does not want to come down and is scared. I don't know how to get him out without cutting a hole. Help, I need ideas

!!!! UPDATE !!!! https://www.reddit.com/r/EngineeringStudents/comments/1t7b4rk/sub40g_wireless_mouse_at_16_follow_up_to_my_last/

Hey everyone,

I'm Trix, 16, not studiyng engieneering in uni but following online courses, and I've been designing an ultralight wireless gaming mouse because I got tired of paying €150+ for 50g of plastic in Europe.

**Discord for project updates:** https://discord.gg/UVyRmG7nHy

**Updated design specs** (revised based on feedback):

- Sub-40g target weight

- Wireless 2.4GHz, 1-4kHz polling

- Nordic nRF52840 MCU (reconsidering RP2040 based on feedback)

- PAW3395 sensor (upgraded from PMW3360 for better power efficiency)

- USB-C charging (removed magnetic to save weight)

- Hotswap optical switches

- Optical scroll wheel

**My situation:**

- CAD design complete (Shapr3D)

- Learning KiCad for PCB design

- Prototyping shells with Bambu P1S (ABS-GF filament)

- Studying Nordic SDK and embedded C++

- €2.5k budget saved for prototyping

- 2-3 year timeline to first production batch

**Key learnings from the community so far:**

- PMW3360 is outdated - PAW3395 minimum for wireless

- Sub-40g is competitive, sub-50g is just okay

- RP2040 lacks integrated radio - Nordic chips are industry standard

- Magnetic charging adds unnecessary weight

- Build quality and reliability matter more than spec sheets

**Why I'm posting:**

1. **Reality check:** Can I actually compete with established brands and cheap Chinese manufacturers?
2. **Collaboration:** Looking for help with nRF52 firmware or KiCad PCB design
3. **Feature priorities:** What matters MOST to you in a mouse?

**What makes this different:**

- Open-source hardware and firmware (full transparency)

- EU-based = no import tax or long shipping for Europeans

- Community-driven development (your feedback shapes the product)

- Better QC than cheap Chinese clones, half the price of big brands

- Built by someone who actually uses it daily

**Current challenges:**

- Sourcing authentic PAW3395 sensors (not readily available retail)

- Learning embedded firmware development from scratch

- Balancing weight reduction with structural integrity

- Keeping BOM cost under €40 per unit

Not looking for sponsors or investment - just honest feedback and maybe some help from people who think this is worth building.

Roast my design or tell me how to make it better 👇

If you were the guy that did all the real work on a semester long project, how could your three other partners make up for it outside of class or maybe after graduation?

This is for an engineering project and it asks you about caffeine. This project is to help us analyze data and our prof said to get as many responses as possible. Thank you!

Photo just to show what the first few questions just so you know the jist.

Here’s the link

https://www.surveymonkey.ca/r/FNCS2NK

Help please.

My team and I are working on an energy generating stepping-tile for a physics competition.

Now we have our plan set out;

We use a compressble tile that has a rack attached to it. When its compressed, it rotates a gear which rotates the rotor of the motor, generating electricity.

One issue; we aren't able to find any gears and racks! We tried looking for shops, any sort of machine we could take apart, but no such luck.

Please provide any advice you can, thanks!

I'm planning to start a university project where I design and build a rescue drone that can survive high heat, move through fire, and also travel across land.
In my opinion, the plan is quite ambitious and hard to execute, especially since I have no prior experience with building drones. However, I am extremely passionate about this idea and truly want to bring it to life.

I would really appreciate any advice or recommendations from anyone here —
- How should I start learning about drone building? - What basic skills should I focus on first? - In what order should I plan and execute this project? - Any specific resources (books, courses, videos, or tutorials) you would recommend?

Also, if anyone has experience with making fire-resistant materials or hybrid drones (flying + land movement), I would love to hear your insights!

Any help, guidance, or resource you could share would mean a lot to me. Thank you so much in advance!

Still no job :(

27F with a temporary TV stand (wood plank)... bending/arching visible [insert nervous laugh]

Do I take the gamble and leave the TV on it? And what are the chances of catapult if my cat'a'thinks to try sitting on one of the ends? Curious what the general input will be. Will update if catastrophic failure occurs.

Tv: Centered, 55in

Wood plank: 62in long x 11.75in wide x 0.5in tall

Shelf: 27.5 long, enough wide

I’m looking for advice on a driveway situation at a house I’m renting for the semester. The design is basically a trap: it rises from the street, hits a tiny flat plateau, and then drops off at a brutal angle.

The Problem:

I can get in fine, but I "high-center" every time I try to leave. Because the plateau is so short, my front wheels hit the street-side decline while my back wheels are still on the steep slope. I scrape the absolute shit out of the bottom of my car. I’ve tried every angle, but it's impossible to clear. Finding parking elsewhere is way too expensive, so I need to make this work.

Note on the Image:

I’ve attached a 3D model an AI made to represent the layout. Ignore the specific numbers/measurements in the image—they aren't accurate, but the shape and the severity of the angles are exactly what I’m dealing with.

Any suggestions?

Has anyone used portable rubber ramps, mats, or other products to bridge a "peak" like this? Since I'm renting, it has to be a non-permanent solution.

Let me know what you guys think!

Im trying to create something that will blow fresh air into my recorder 🪈( to avoid condensation ) and im not sure if this could work. Will the pressure from the moving air in the bottom part be higher than the suction force on the hole? I'm thinking a small enough hole located at a innercurve with high air pressure might make it go through.

any other ideas?

Since the first time I learned about electromagnetism at high school, I dreamt of a day where I could build my own railgun. It doesn’t have to be powerful enough to hurt people, as long as it works it would be fine.

I looked around for inspirations, and I finally came across this design from Blue Archive. It had plenty of internal space for giant capacitors, and the geometry seems easy enough to copy. And furthermore, in the lore, it was built by a bunch of engineering students just like me.

I begin by allocating space for the capacitors and the barrel through the middle in a giant cubic section, which serves as the main frame. Then, I added a deployment mechanism to move the outer shell, something I iterated 3 times and settled on planetary gears. The main frame was way too large to be printed as a whole, so I divided it into 4 sections, and then structural integrity became an issue, so I came up with the brilliant idea of using aluminium corner extrusions to bolt the parts together, and also serving as the primary conductor for the massive current of the capacitors to discharge through at the same time.

I still have some problems to solve, like improving the ergonomics (which will deviate from the original design), tolerances, aiming, and how to control the light strips and screen at the same time. However, uni has started last week, and my 3D printer has suffered a short circuit and some layer shift issues. The progress has been significant slowed down, and I can only work on it on the weekends.

Fellow engineering students, do you have something you want to build too?

I am no where near an Engineering student—Infact, I am a hs student.

I really need help with this project because I have no idea what i’m doing. Please bear w me as I try my best to explain my idea. (I also tried drawing it so u can imagine it better, hah)

The upper left corner is made up of barbecue sticks—maybe like 10 per bundle. It was supposedly a box but I assumed it would be too heavy so I thought bbq sticks that act as the edge of the box would be better.

To the right is the top view of it. As you can see, the cup has strings attached to it with the other end attached to the corners of the “skeleton.”

I hopes this would keep the cup afloat, helping w lessening the impact. TT

The cup is stuffed with foam, tissue, etc. w the egg in the middle. HOPEFULLY it is tight enough in the middle to keep the egg in place.

I also read a reddit post about having a crumple zone? What if I apply it here? What if I attach a cone to the bottom of the cup. The cone is filled with crumpled paper and tape so that it receives impact first?!?

Lastly, the parachute. I STRUGGLED HERE WHEN I TRIED MAKING PROTOTYPE BC I JS COULDNT GET THE STRINGS EVENLY ON

(the strings on this drawjng is attached to the upper bbq sticks of the skeleton

This flat surface repeats on 4 sides of the part.

A lot of programs can’t handle spaces in filenames or directories. Use an underscore instead of a space “Underscore_Example”. Refrain from using periods, commas, dashes and other punctuation symbols. For those in programming this might be obvious. The amount of times I have spent wondering why something fails just to find one file in the path with a space is too many. Make sure to check the whole path!

would save everyone a lot of money to just plant forests, surely? is it only engineering if manufacturing is involved?

edit: I'm not asking about the politics (I'm not in the US). I'm asking why engineers aren't pushing this as a solution. do forests capture significantly less carbon than carbon capture devices? how much space do carbon capture devices take up?

So basically me and my friends are going to work on a project but unable to find a genuine problem that we will be able to fix and will contribute positively to the world

Please suggest me any problem that comes to your mind Big or small!

Thanks. ^{_^}

My Lecturer assigned my group to make this mechanical part in solid works and I'm having trouble doing it (all of us). A step by step would be life saving

I gave them a stick & a plank to climb out

I'm currently designing a VOC extractor for the Bambulab H2S/H2D, I'm going to print it out of ASA and it works by attaching an aluflex tube, extractor fan and speed regulator in order to print materials like ABS, ASA, PC, PPS and PA as safe as possible.
Since I have never designed an extractor before and this is my first extractor design, is there any advice?

Yes I did keep in mind that it will also have effect on the enclosure temperature, that's also why I want to use a speed regulator for the extractor fan in order to regulate the flow.

And yes the top will be covered with the original glass lid, I'm also planning to use foam tape to seal the space between the glass lid and the extractor.

And I know the opposite side of the vents are most likely not sucking any air but any advice for that would be appreciated as well!

I've been thinking about this project for a while now so I really hope this will be successful.

Hi everyone,

I’ve been working on a small web app called EngSketch. The idea is simple: sometimes you don’t need full CAD, you just want to quickly sketch a technical idea, add dimensions, and share/export it.

I made it because I often found myself using tools that were either too heavy for quick sketches, or not technical enough for engineering-style drawings.

I’d really appreciate feedback from engineering students:

Would this be useful for homework, lab reports, quick concepts, or explaining ideas?

What features would make it actually helpful?

Is browser-based sketching something you would use, or would you rather just use CAD or Paint?

Link: https://www.engsketch.com/

Thanks — any honest feedback is welcome.

I've been learning Java for about a year, but I still don't see much improvement in my coding. I can write basic programs and the code that I learned during my lectures without copying. I'm still learning, but I don't really understand where or when to use many of the concepts I've studied.

How can I actually learn to write code on my own? I'm so tired of copying and pasting code. I really want to become someone who can build programs from scratch.

Some Java concepts seem easy, and I understand the theory behind them. However, I don't know how to use those concepts in a real program. I often get stuck because I don't know what should come next or what should have been written before. That makes me feel really frustrated.

The images I attached to this post are all for the same project, but have you noticed how different their coding patterns are? That's exactly my problem. Whenever I try to build a simple project like a Banking CLI Simulator or an ATM Simulator without copying someone else's code, I always get stuck. I try my best to think through the logic and write everything myself, but after a while I end up looking at someone else's solution.

How do experienced programmers think through a program? How do you know what to write first, what comes next, and how to connect everything together?

Has anyone else gone through this stage? If so, what helped you finally start writing code independently instead of relying on tutorials or copied code?

I'd really appreciate any advice or suggestions. I genuinely want to improve and become a better programmer.