Really cool idea. I’d just go with an accelerometer
sorry just found that with a really quick google search on a German site, but you’ll get what I mean :)

https://eckstein-shop.de/GY-346-Accelerometer-3-Achsen-Beschleunigungssensor-ADXL346-fuer-Arduino-Raspberry-Pi?curr=EUR&gclid=CjwKCAjwmq3kBRB_EiwAJkNDpx2x0CsKx1VTSGcU_NeQNqVU1vRg7enu1Nt0FTXsmRLgGDGBaxgYFxoChuMQAvD_BwE