#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.