The last week was dedicated to the development of our PCB, which is now almost done, and to the finalization of our electronic circuit. A severe modification happened in our design: we decided to get rid of the atmega328p (it is the processor of the Arduino boards) and to do everything using the esp8266. Indeed, it turned out that those modules are extremely easy to program (and to debug) using the USB to TTL cables. Since their pinouts is enough for our application, we will simply use the esp8266 without any other procesor. It will make our PCB sensibly easier, ans smaller.
So far, here is precisely what we have already working: we have a board with an esp8266 that is flashable using a USB to UART cable. This esp8266 is connected to our touch sensor and read (using its only analog port) the data from the sensor, at a rate that is defined in the code.Then, it sends it a local server programmed on a raspberry-pi using UDP protocol (it’s the protocol to make streaming of data). The server correctly receives it, and will generate some graphics to illustrate those logs. All of this works with an independant alimentation giving 3.3v with about 250mA. Malik have been working on the generation of the graphics and we are now going to deploy it to the raspberry pi.
During the incoming week, we are going to work on the generation of graphism especially using more than one sensor. Even if we don’t have multiple sensors, it is not very difficult to ‘simulate’ one of those sensors using someone’s computer and sending data via the UDP protocol. Even with a phone it would be doable.
So far, our touch sensor is a very tiny little circuit that we bought. At first, we wanted to make this circuit only using some passive elements. Because of the special conditions, we didn’t have the material to make this circuit and that is why we decided to use an already made, standalone, board. But we will start again working on a circuit of our own, since we got some more material. However, as we would like to order our first pcbs soon, we believe the first pcb will not include them and will include the already made board.
Thank you for reading this and cheers all !