Hi, I am new to Arduino, but well versed in practical electronics, engineering and project construction.
I am also a keen breadmaker of long standing and enjoy projects related to this that can improve the quality of the bread I bake, or make life easier.
After mixing bread dough, it is put into a large container where it undergoes what is known as bulk fermentation. This is partly to develop the strength of the dough, but also to improve flavour as biochemical processes take place, CO2 is given off and the dough rises. Bulk fermentation of sourdough lasts anything from 2 hours up to 6 or more.
One measure of when bulk is complete is how much the dough has expanded in volume. For sourdough an increase of 40-50% is considered about right. Measuring the dough volume can be tricky. It's easy if the dough surface is flat, but as fermentaion progresses, the dough develops a domed top and also has individual rounded peaks and troughs - a bit like a mountain range. This makes it difficult to measure volume to determine % increase.
I have developed a manual measuring system to do it:
but I thought it would be great if I could do it with an Arduino and multiple ultrasonic sensors such as the HC-SR04. I have read that certain techniques need to be employed to improve the accuracy of this sensor.
Here are some design specifications:
- ideally 20 sensors, but 10 may do, fixed in an array in a bowl lid, possibly made of acrylic
- bowl diameter 280mm
- accuracy +/- 1mm, but would accept 2mm
- distance 60mm - 10mm (although these could be increased by 10mm by having a raised lid)
- distance calculation (and hence volume) should weight results from outer sensors because outer annuli of the circular bowl surface will have more area associated with them
Please advise feasibility and how I might go about this.