Schematic Devlog #3 !

I have added and wired the following :

• The weight sensing circuit (a SC134 load cell and a HX711 amplifier) :

• The LSM6DS3 accelerometer & gyroscope :

• An LED Ring and Buzzer :

What’s left/next ?

I am currently working on the Charging and Battery circuit, and after that im pretty much done !

Schematic devlog #2

I HATE KiCad. If you didn’t look at my last devlog, PLEASE DO ! In the last one i was rather happy about having to not have to install the HX711’s KiCad symbol and that it was built in. WELL unfortunately KiCad let me down - it uses the damn IC symbol ! Anyway, i had to install the symbol myself, then add it, and this time the pins where finally correct ! i aslo finished wiring :

• the LSM6DS3 Accelerometer/Gyroscope
• The WS2812B LED ring (im thinking of using it as a status showing thing)

I will be working on after a small break :

• wiring my Buzzer (to notify user to drink water) with a resistor and transistor SHOUT OUT TO MY PHYSICS TEACHER
• maybe adding a Motor for nice vibration feedback ?
• working out the power/charging/flashing

Started my schematic !

I have now started designing the schematic for the AquaPuck TM (just kidding lmao) !

Im using KiCad, and found the footprint for my microcontroller (the ESP32-c3-supermini) online (this time with correct pin names). Then i added my Weight sensor circuit, which uses a SC134 load cell, and a HX711 voltage amplifier/analog to digital converter ( so that the microcontroller can actually measure ). The HX711 footprint/symbol was built in to KiCad, and was easy to find. for the load cell i didn’t need a footprint/symbol, as it wont be soldered on the PCB, but instead will go ON the Puck (in the physics force path).

#Done with all my research !

So basically i got the idea for a smart water bottle at a Jugend Hackt Hackathon i attended last weekend (June 19. - 21.) in Berlin - it was my project for that hackathon - one that at the end was only a prototype that didn’t work.

##THE v0 PROTOTYPE :

The Hackathon prototype (see below) worked like this :

• we used a barometer to measure the pressure of the water, and through a bit of calibration the weight

• we added a accelerometer & gyroscope (2 in 1) chip to the side, so we know when it is tilted (use formula for pressure - water height - density, etc. - this part was done by a different group member so idk)

• everything worked over a ESP32-c5 chip and the measurements were sent over a wifi UDP stream

• Bottom of bottle replaced with balloon so sensor can get actual pressure

###What did’nt work :

• We used a wrong type of sensor - a barometer measures air pressure not water pressure
• it needed to be waterproofed, but still be able to feel the pressure of the water - we didnt have the material to waterproof it properly, so we used a makeshift solution and well, it didnt work - water got on chip - and it got WASTED
• Our 3D print had wrong measurements and we couldn’t reprint as no time was left.

Prototype V2 Planning

• Instead of adding stuff to a bottle making holes, drilling, deforming the bottle, and having wire salad, we will this time just design a small puck that can be taped to a bottle
• This time we wont measure pressure, but instead weight (our puck is a mini scale) with a load cell
• the gyro/accelerometer stays on the bottom this time
• We can take accurate measurements
• This time, i actually will think about PHYSICS before electronics, so we have a working prototype
• careful planning, parts lists, and thinking ahead ( hoe do we attach ? what is the force path ? why not use other sensors ? etc …
• accept the fact that while tilted, it wont measure, as that would be MUCH too hard to implement and would need at least half an year

Why this ?

I went through a lot of methods for measuring with ChatGPT and Deepseek

We thought about :

• Ultrasonic : condensation is a problem, water moving would make measurements wrong completely, and again waterproofing
• tension measurer - something that goes between cap and bottle : way too expensive sensor, complex 3d print, lots of physiscs at play, really hard to design
• pressure : didnt work in prototype v0, wouldnt work better here
• ToF : same problem as ultrasonic, and even less accurate

So I sacrificed the measuring while tilted, and went with this sensing method.

Done with all my research, brainstorming, and idea finding - was feeling bit lazy cause I came back from a whole 3 day Hackathon and only did research - but it took 3 Damn HOURS