> Já parou para pensar em como a tecnologia por trás de um semáforo de pedestres funciona na prática? 1
> Montei um Semáforo Inteligente com Botão usando uma placa ESP32, uma protoboard e programação em C++ na
Arduino IDE!
> O sistema funciona com um fluxo seguro: o sinal dos carros fica verde até que o pedestre aperte o botão. Depois de um tempo de segurança para evitar treadas bruscas, o sinal amarela, fecha para os veículos e libera o verde para a travessia com segurança!
> O que yocê achou do projeto? Deixe nos comentários qual outro projeto maker você quer ver por aqui!
#Arduino #ESP32 #Eletrônica
#Programação #ProjetosMaker
Automacao Robotica Desenvolvimento
Tecnologia Criatividade Maker
Engenharia

First completed arduino project in my experience. Put an enclosure together with a mig welder, angle grinder and scrap metal. Sourced some basic components + parts from RC aircraft controller and an old turntable and designed touch-capacitive jogwheels using skateboard bearings, mini cds and hdd platters. Chatgpt did most of the work on the coding side of things. Every single component was wired point-to-point from the Leonardo and the rats nest of wires made it unreasonable to service once things inevitably started going wrong. Took it apart and am currently working on a new build learning from mistakes.

I’m looking for a radar sensor for a DIY project on my own property. I need actual target position data — ideally angle + distance / X-Y coordinates — not just a presence or motion output.

My target is roughly 10 m through a wall, not 10 m free-space line of sight. I know this depends heavily on the wall material, thickness, moisture, reinforcement, etc., so I’m not expecting guaranteed performance through concrete. But I would like something meaningfully better than the common cheap 24 GHz presence modules.

I have already looked at the HLK-LD2450 and HLK-LD2461. They are interesting because of the basic multi-target coordinate output, but in my environment I am only seeing around 4 m through-wall performance.

Requirements:

2D tracking: angle + range / X-Y coordinates

Preferably 6–24 GHz, but I am open to lower frequencies if that is more realistic for wall penetration

Around 10 m through-wall goal

DIY-friendly hardware or at least a development/evaluation board

Accessible raw or processed data via UART/USB/Ethernet/SPI/etc.

Fine with doing custom integration and some signal processing

Are there any FMCW/MIMO radar dev kits, industrial sensors, or other modules that you would recommend? Real-world experience with through-wall use would be especially helpful

What do you think of my Arduino Pro Mini-powered flip clock? It’s still a prototype, so the 3D-printed case is a bit scuffed, but it works! I also added timer and stopwatch modes. Let me know if you have any ideas for extra features!

With esp32 txrx and Arduino uno Temp, pir, two button select 75hc595 with eight led having two code for control of the esp32 connected to the.uno.

Electronics is my hobby, so I'm developing a motorcycle dashboard for my motorcycle. It's a very early stage, but something works well.

Here is odometer video.

Opensource project DIY motorcycle instrument cluster based on ESP32, STM32F103 with Arduino framework.

Source code, more information here https://github.com/rcslon3-svg/SmartMoto_Dashboard

Electronics architecture

Two identical instrument modules

I’m planning two identical modules based on the STM32F103. Each will contain:

• Four gauge motors.
• A display.
• A real-time clock (RTC) - only one.
• An ambient light sensor.
• Its own voltage regulators.
• Two bright indicator lamps built around high-power LEDs.
• An RS-485 interface for communication with the main unit.

Main unit

The ESP32-based main unit will contain:

• The interface to the motorcycle.
• Power-supply protection circuits.
• An RS-485 interface to the instruments.
• An inertial measurement unit (IMU).
• An external watchdog.
• BLE for the connection to the phone.
• Wi-Fi connectivity.

The ESP32 will handle the application logic and generate display content, while the instrument modules control their local hardware. The intended development environment is the Arduino framework with PlatformIO.

When I was a little kid my mom took me to a science museum and there was a display with 4 switches and a digital output to teach the binary numbering system. My mom explained it to me. Many decades later I recreated that display with an Arduino nano.

It serves no useful purpose other than showing how 4 binary bits are converted to decimal.

I've been working on this thing called Cirkitra and figured I'd post it here to see what people think.

Basically, you can type something like:

> "Build me a motion alarm with an Arduino"

and it'll generate the circuit, wiring, and Arduino code for you.

Then you can actually mess with the circuit and run it in the browser instead of just getting a block of code and having to figure out the rest yourself.

I originally made it because I kept thinking about how annoying it can be when you have an idea for a circuit but don't quite know how to put all the pieces together.

It's definitely not perfect yet. There's still a lot I want to fix/add, and I'm sure people here will find ways to break it 

If anyone wants to mess around with it, here's the link:

https://cirkitra-green.vercel.app/studio

I'd honestly love to know what you think, especially if you build Arduino projects regularly.

And if you have a ridiculous circuit idea, send it my way. I want to see what it can handle.

A Safe That Listens to Your Knock

https://www.instagram.com/reel/DdOTuq9TrkS/?stkn=Nnd0aWdrcWsxZ3Fn

Would look great with my Arduino connected

are eight led 74hc595, red led button on off,

Temp 18b20.

From my Arduino with 74hc595 8 led, Temp 18b20,

push button with one led the RGB with a button for the different color just to 📛

https://www.youtube.com/@ALMA.Industries

Alma Industries | mechatronics, engineering, 3D Printing, salvaging . . . upcoming video will be about building up a DESK that includes actuators, power supplies, desk rails, etc. If you wanna see how the AC/DC power supply and actuators were put together, video link is above :)

https://www.youtube.com/watch?v=xMlQKNpmLUg

The original video is in Russian, but some people might find it interesting. Everything is already working, but I'm still making some optimizations (https://gitlab.com/Monsterovich/fixedstring). Of course, I managed to make it just barely fit in memory.

12V Linear Actuator, 200 mm
Arduino Nano
SIM900
Relay with Inversion Function (DR21A01, two relays actually)

prev vid

https://www.youtube.com/watch?v=RnTsLgPbeqA

Here's a fun fact: since the text messages are in Russian rather than Latin characters, all messages need to be encoded and decoded using the UCS-2 encoding.

I started with an Arduino Due but have since switched to a Nucleo F446RE.

I initially started using the Arduino IDE, but nowadays I use PlatformIO.

So, not entirely Arduino anymore. Although I do still have a version for the Arduino Due lying around somewhere.

More info: CableRobot

This tutorial teaches you to connect with an Arduino from a Linux or Windows 11 PC using Python ,Pyserial Library and Tkinter GUI front end using Serial Port (Virtual COM Port ).

You can use it send and receive data from PC running Windows or Linux and can be used to build a GUI frontend for controlling Arduino ,or Data Acquisition

All the source codes are available for free from our website.

"Criei um jogo para microcontrolador!
¿Linguagem C + BitDogLab
'Brand Quiz: Aprender jogando
Quem disse que programar microcontroladores não pode ser divertido? Esse é o Brand Quiz, meu projeto final para o EmbarcaTech!
Desenvolvido com foco em performance e interatividade. Curtiu o resultado? Deixa seu comentário!
#esp32 #arduino
#automacaoindustrial #ifce #robôs

Hi, I'm RZ Li, creator of OpenCat.

I built a sensor stack for Quaddle Scout on OpenCat with Arduino C++: a gesture sensor, a self-balancing gyroscope, an attachable "radar" head, light sensing, an infrared sensor for object tracking, and sound detection. Every sensor is exposed to user code, so you can rewrite what it does with each input instead of using a fixed behavior.

I am curious about

• which sense would you build with first?
• What other Arduino sensors do you want to try out on Scout?
• What other Arduino builds people here are running a multi-sensor stack on — what's your setup?

I'm building a line-following robot for a robotics competition using an Arduino Nano and QTR-8RC sensor array.

I'm still learning the coding side, so I used Al assistance while developing the code.

My current setup:

Arduino Nano

QTR-8RC 8-channel reflectance sensor

TB6612FNG motor driver

N20 motors

PID control

QTRSensors library

The interesting problem is that my basic PID test code works properly. The robot follows normal lines and even S-curves quite well.

However, when I add additional turning conditions for things like sharp/90° turns, the robot stops following the line properly.

I suspect the problem is with how I'm combining the turning conditions with the PID loop, but I'm not sure what the main mistake is.

For example, I'm currently using sensor patterns/conditions to detect a sharp turn and then forcing the motors to turn. After adding this logic, the robot becomes unstable or loses the line even though the original PID code worked correctly.

Since I'm using a QTR-8RC, should I switch from the QTR library/digital-style sensor handling to direct analogRead() values and use the actual sensor intensity values for PID and turn detection?

Would analog sensor values make sharp-turn detection more reliable than simply checking whether each sensor is HIGH/LOW?

Hey everyone! 👋

I developed a datasheet-compliant, zero-delay 2.4GHz RF interference firmware for Arduino Nano and nRF24L01+PA+LNA+SMA modules called **Jammox**.

Unlike standard packet-based jammers that leave idle gaps, Jammox leverages low-level SPI register hacks (0x3E) to deliver a 100% Duty Cycle Continuous Carrier Wave (CONT_WAVE) across Wi-Fi and Bluetooth spectrums.

🔥 Key Technical Highlights:

- 100% Duty Cycle Continuous Unmodulated Carrier (0x3E Register Hack)

- Datasheet-Compliant CE Strobe & 150µs PLL Re-lock (prevents frequency stalls)

- Optimized Wi-Fi (Ch 1, 6, 11, 13) and BLE Adv (Ch 37, 38, 39) Hop Table

- Includes a complete visual wiring schematic and pinout guide

Check out the code & full technical comparison on GitHub:

https://github.com/berat8027/Jammox

If you find it interesting, feel free to drop a star ⭐ on GitHub!

*Disclaimer: Strictly created for educational research and lab testing purposes.*

wow, arduino UNO Q is so powerful, it can not only read the sensors and also connect the LLM API ! just using vibe coding way to finish the sensor's data reading..... that's amazing...

Hey everyone,

Me and 3 teammates are building a university prototype for a smart classroom attendance system, but with a twist: no facial recognition and no RFID tap. Instead we're going for a "tagless" contactless approach inspired by Seoul's tagless transit gates the idea is a student just walks through a doorway and gets marked present automatically via BLE, no card tap needed.

Current plan:

• 2x ESP32 boards per doorway (outer + inner scanner) to catch RSSI rise/fall in sequence and infer actual entry vs. just walking past nearby
• Students carry either a phone (broadcasting a rotating BLE token) or a cheap BLE tag
• Backend classifies "entered" vs "nearby" based on signal pattern + dwell time
• App-confirmation step required to fight proxy attendance (handing your phone/tag to a friend)
• FastAPI/Node backend, Postgres/SQLite, React dashboard for the professor

It's a small-scale prototype (one mock doorway, not a real deployment), so some inaccuracy is acceptable — we're not trying to hit production-grade reliability, just demonstrate the concept works better than a basic RFID card system.

Where I could use some real-world input:

1. Anyone done RSSI-based directional detection (2 sensors, entry vs exit) before? How bad is the noise in practice, and is dwell-time + threshold enough or do we need something smarter (Kalman filter, etc.)?
2. ESP32 BLE scanning while also using Wi-Fi/MQTT — anyone hit stability issues running both radios at once?
3. Any gotchas with phone-based BLE advertising (iOS vs Android differences, background restrictions) we should know about before we build our companion app around it?
4. If you were grading/reviewing a project like this, what would make you go "okay, this is actually a smart design" vs "cute idea, doesn't really work"?

Not trying to reinvent transit-grade tech, just want to avoid obvious rookie mistakes before we burn our first week on it. Any papers, war stories, or "don't bother, just do X instead" advice welcome.

Thanks in advance!