​The homing signal board on my Xiaomi Mi Robot Vacuum-Mop 2 Pro (MJST1SHW) charging dock is damaged, and the vacuum can no longer detect the dock to return for charging. Finding a standalone replacement dock on the second-hand market isn't working out, as sellers are pricing them almost as high as a complete used setup.

​I’m currently trying to build a replacement beacon using an Arduino/ESP32. I set up two IR LEDs for the left and two for the right, modulated at 38kHz. However, the vacuum doesn't respond to the custom beacons at all during its docking routine.

​Does anyone have experience generating these specific homing signals? I would greatly appreciate any insights into the correct IR protocol, pulse timings, or data payloads required to get the vacuum to recognize the dock.

This is a repost, sorry I forgot the comment.

So this is us driving around our lego technics compatible robot which uses the esp32s3 sense on the back porch. You can see the latency is super low and the fps is about 20 fps. We imagine it's like playing doom2 but in the real world so it does not have to be super high def but has to be realtime for interfacing with the environment. We released the stls and the firmware if you have your own esp32s3 you can make your own, we handle all the stuff like wifi provisioning, pin selection for motors, etc, all you need is a web browser!

I've been working on an open-source ESP32-S3 firmware called ESP32 Tailnet Gateway.

It turns a supported ESP32-S3 board into a lightweight Tailscale/Headscale gateway and independent recovery node.

Features:

• Remote access to selected TCP/UDP services.
• Wake-on-LAN for NAS and PCs with reachability checks.
• Optional IoT Wi-Fi access point.
• MQTT and Home Assistant Discovery.
• Notifications, event history and resource monitoring.
• Browser-based firmware installation and Web UI.

It runs on ESP32-S3 N8R8/N16R8 hardware with 8 MB octal PSRAM.

Ethernet and cellular options are still experimental. It's not intended to replace a full Linux router.

The firmware builds on Csontikka's ESP32 subnet-router and MicroLink work.

GitHub: https://github.com/Mattboxx/esp32-tailnet-gateway

Web installer: https://mattboxx.github.io/esp32-tailnet-gateway/install-firmware/

I'd love feedback from other ESP32 developers!

Does slime tech count ? 😂

"Recommend me robot projects that I can do on my own (mainly to improve myself mechanically) and that won't require a lot of money."

☐ Deli D991EX calculator — 500–700 EGP (Buy first; inspect its internals)
☐ ESP32-C3 SuperMini — 240–400 EGP (Wi-Fi microcontroller)
☐ OLED screen (I²C, 3.3V-compatible) — 150–300 EGP (Choose size after measuring)
☐ 3.7V protected LiPo battery — 125–200 EGP (Choose capacity and thickness after measuring)
☐ TP4056 charger with protection — 20–40 EGP (Must set safe charging current)
☐ 3.3V buck-boost or suitable 5V boost — 40–120 EGP (Regulated power for ESP32)
☐ MCP23017 GPIO expander breakout — 200–350 EGP (Subject to keypad testing)
☐ Thin wires, small switch, insulation — 100–180 EGP (Prefer 30 AWG wires)
☐ Small PCB, connectors, soldering supplies — 100–250 EGP (For electrical connections and mounting)
☐ USB-C data cable — 0–100 EGP (No purchase if already owned)

Tell me if I need to adjust anything?

It's got a lot of issues still. The clock drifts, the arpeggiator button (not used in video) uses the wrong grid over the midi channel, and the sustain is constantly on.

If anyone has any tips, I'd love to hear them!

Using an Arduino Uno R3, a 16x2 LCD, Joystick, 4 buttons, and connecting to a DAW via Hairless MIDI and LoopMidi.

hey guys. this post did very well on reddit, it had 60 thousand views, so i am reposting it here. I am also going to work on a video on youtube of a homemade Phonautograph, which was the predecessor to the phonograph, it will be out soon enough. you will be able to watch it once it goes up on my youtube channel, youtube.com/@mivetopianow

As the title states- I recycled my previous Acer Spin 3 (sp315) laptop screen to turn it into a DIY monitor so to say. I bought the control board for the screen as well as the proper power cord for it and have plugged it in and turned it on.

Heres where I have issues: the screen does turn on and off via the control board on/off switch, but the screen itself does not display anything asides from a grey rectangle in the middle of the screen- I'd acquaint it to if you were watching a vertically displayed ad on youtube in landscape view. Not quite sure if maybe the screen got damaged during the process of removal from the laptop casing and disconnection process or if I need to do something additionally to make the screen display.

Anybody have any sort of insight into this? Additional details:

-Touch Screen laptop

-NXGK9AA0116430971F7200 sin code for the laptop itself

-LP156WF6-SPK4 control board model number

If anybody has any insight or support they wouldn't mind providing that would be great. if this project is dead in the ground that is okay, it was worth a shot and for my learning :). If any additional information is needed I will gladly provide it the best I can!

UPDATE: Photos of additional numbers:



Hi everyone,

I am planning to build a homemade DIY anemometer for a school/university project. Before I start assembling, I want to make sure I use the best household materials to get smooth rotation and decent accuracy.

My Plan & Ideas so far:

• Cups: Plastic/paper cups or ping pong balls cut in half.
• Pivot/Axis: Looking for a low-friction way to make it spin freely (e.g., using a fidget spinner, needle-in-eraser, or pencil tip).

Questions I have:

1. What is the most reliable low-friction central spindle/bearing mechanism using everyday household items?
2. How can I ensure proper balance so wind catches all sides equally?
3. What’s the easiest way to count rotations or calibrate it to measure wind speed without expensive sensors?

If you have built one before or have tips/guides on what works best

I was wanting to see if anyone has made a homeade DIY police radar detector. If so, could you point me in the right direction and give pointers? Thanks in advance.

i've been learning more about how smart technology dan help homeowners manage their energy usage, especially when it comes to running an AC system.

some mini split heat pumps, including cozeware models, offer app-based controls and voice control. i'm curious about how DIY tech enthusiast monitor the actual electricity consumption of these systems and track changes in energy usage over time.

would a dedicated energy monitor be a practical option or are there other DIY setups worth exploring? has anyone here tried setting up something similar?

It's still a prototype, but so far it's great.

Hey everyone, I'm a high school student in Kathmandu, Nepal, and I'm looking for a project idea that's actually hard and useful, not another "blink an LED" or basic Arduino gadget.

Where I'm at:

• I run my school's robotics club
• I do PCB design (KiCad/EasyEDA) and freelance on Fiverr
• I've built a self-balancing robot (MPU6050, filtering, PID), a line follower, an ultrasonic radar, a water rocket, and an arcade game
• Comfortable with Arduino, ESP32, RP2040, MicroPython, Python, and Fusion 360

What I want:

• A project that solves a real problem, ideally one that matters in a place like Nepal (earthquakes, floods, water, health, accessibility, etc.)
• Hard enough to stretch me for a few months, where I have to measure, test, and validate, not just get it working once
• Something I can document properly and release open-source

Constraints:

• Very small budget (a few thousand NPR at most), so mostly cheap parts
• I can only work on it a few hours a day after school
• Parts need to be buyable in Kathmandu or on Daraz

Parts I already have: Arduino Uno/Nano, Raspberry Pi Pico, OLED, TT motors, motor driver, servo, ultrasonic and IR sensors, perfboard, soldering iron.

I've considered things like a low-cost earthquake early-warning sensor network, but I'd love to hear other ideas, and honest feedback on what's realistic. What would you build in my position?

Thanks!

My engineering group at Clarksburg High School in Maryland and I are currently developing a POTS-specific monitoring and alerting device and app. To build credibility, we have spoken with biomedical engineers and doctors worldwide (New Zealand, John hopkins, India, Canada, and Germany), gathered feedback, and are now building a prototype. The reason I'm posting this is that we need real feedback from people with POTS to know specifically what is important to incorporate and to better our understanding.

If anyone could fill out this form, it would mean the world to us!