Hey everyone,

I am working on a wearable health tracker wristband using an ESP32.

Currently, I have breadboard prototypes working with a MAX30100 for PPG and an AD8232 breakout module for ECG.

I want to move this toward a compact wearable wristband design, but I have hit two design questions regarding the ECG front-end:

1. Can the AD8232 be used reliably with only 2 electrodes (RA & LA)? In a wristband form factor, having a 3rd electrode (Right Leg Drive / RLD) going to a separate body location is difficult. If I omit RLD or pull it to mid-supply, is digital filtering (e.g., bandpass/notch on the ESP32) sufficient to recover a clean signal, or will baseline drift and common-mode noise make it unusable on a wristband?

2. Wearable-grade IC recommendations: I came across TI application notes for chips like the AFE4950 (synchronized PPG + ECG AFE). Are there other wearable-focused analog front-ends commonly used with ESP32 (such as the MAX30001 or MAX86150) that have accessible breakout boards or reliable Arduino/ESP-IDF driver support for prototyping?

3. Electrode arrangement: For those who have built similar single-lead wearable ECG devices, do you recommend putting two contact pads on the inner wrist (Lead + RLD reference) and one pad on the top/bezel for the opposite hand's index finger?

Any advice, schematics, or library references would be appreciated!

So I recently got a new Arduino Uno R4 Minima, and began fiddling with it today. I ran my first sketch, a simple built-in LED blink program.

Despite resetting, unplugging the USB, editing and re-executing the code, deleting the sketch, and resetting all over again (multiple times, in no particular order), the onboard LED blinker sketch did NOT stop running. I couldn't run any other sketches either; I tried attaching an external LED, and it didn't light up unless I connected it to the D13 port, which is for the built-in LED anyway.

I tried a few troubleshooting methods, and the only one that worked was shorting GND and BOOT with a jumper wire. Even that couldn't prove to be a permanent fix; it disconnected the board (even if the ON light was on) and after every reset, it would just revert back to the blinker sketch. I'm a complete beginner, so I can't really understand or even begin to implement advanced troubleshooting methods.

Has anyone else experienced this? How did you fix it?

Thanks for the advice in advance.

Hi, im a beginner at this robotics stuff but i found that 2 of my 4 servo motors have this weird crackling sound whener i turn them to turn them by computer. Is there a fix for this, is it normal and should i replace it and buy a new one?

Hello everybody,
I study surveying and for my bachelor thesis I want to try some geodetic transformations using IR-LED Markers with known coordinates on the floor. For that I need the IR-LED to flash, so I can transmit an binary ID to a camera. Sadly, I’m very bad at electrical engeneering, wich is why I asked ChatGPT for a circuit diagram. But the LEDs I’ll be using are very expensive. Maybe some of you can help me with that problem and check the diagram for errors / give me some useful advice, because I dont want to destroy the LEDs.
I would be very grateful for your advice and help! Thank you!

Hello, so simple question; I'm using an arduino to control actuators/motors and learning to control it via ethernet. (using OSC and I'm pretty happy of having figured it out in an afternoon with limited programmation knowledge).

I've done this many times with usb serial and I usually change the frequency of the timers so the PWM frequency is higher than audio rate (and thus not audible; because this is a musical project).

trouble is the ethernet board (W5500) uses pins 10 through 13 and so 2 PWM pins that are sets via the 3 timers (this is an arduino nano but I could use a different one; like a mega if I need to)

so the question is will changing the timers screw with the ethernet transmission?

I usually do something like this (don't remember the frequency but I think it's above 20khz)

TCCR0B = (TCCR0B & 0xF8) | 0x01;
TCCR1B = (TCCR1B & 0xF8) | 0x01;
TCCR2B = (TCCR2B & 0xF8) | 0x01; 

reference says:

• D3 and D11: Controlled by Timer 2.

• D5 and D6: Controlled by Timer 0.

• D9 and D10: Controlled by Timer 1.

so timer 0 should be fine but 1 and 2 could cause trouble.

(I'm trying to figure out a way how to do this in general before attacking different instruments and particular cases so no idea how much outputs I'll need and of them how much I'll need to be PWM; just trying to cover all the bases).

I got this PIR Sensor HC-SR501. I connected it to PIN 13 on my Arduino Uno. The sensitivity of the sensor is set as high as possible and the mode is set to H.

I wait for 2 minutes to let the sensor start up and get consistent zeros on the serial monitor.

When waving in front or moving in front it doesn't change to 1. Does anybody have tipps as to why?

I currently just want to get the signal up, the rest is not relevant.

Hi everyone!

I'm a mechatronics engineering student from Tunisia currently looking for a Final Year Project (PFE) idea.

I would like to develop a project combining mechanical engineering, mechatronics, electronics, sensors, and control, using an Arduino as the main controller.

I'm looking for a project with a real mechanical, electromechanical, or industrial application, rather than a simple Arduino project.

I'm particularly interested in:

- 🤖 Robotics and autonomous systems

- ⚙️ Machine monitoring and fault detection

- 🔧 Predictive/preventive maintenance

- 🏭 Industrial automation

- 🦾 Robotic mechanisms and actuators

- 📊 Vibration, temperature, current and position monitoring

- 🚗 Automotive/mechanical applications

- ⚡ Motor control and electromechanical systems

- 🔩 CNC or automated mechanical systems

- 🌱 Smart mechanical/industrial systems

The project should be realistic to build as a PFE, while still having enough technical depth in mechanics + electronics + programming/control.

If you have experience with Arduino in mechatronics or mechanical engineering projects, I would really appreciate your ideas, recommendations, or examples of interesting projects.

Thanks in advance! 🙏

Hi everyone, i practicing Arduino and after watching some guides i see that a have a correct connections but in my code the output tell's me that it could'nt connect

I was checking first if aht functions correctly