small PCB product with ESP and GPRS GPS support
This is my first try at Freelancer.com and in electronics, so please help and be patient!
I would like to produce a small circuit (as for firmware and software, it is not requested in this phase: I am trying to code myself), composed in this way:
- there are one or more devices acting as slaves, connected via Wifi to a master with GSM+GPS.
Slaves and master are identical in design and components, except that master embedds a GPRS+GSM+GPS module too.
In practice, I ask for the development of the master PCB having GSM+GPS module, taking into account that slaves are based on the same exact project only without GSM+GPS module;
- masters and slaves are battery operated and must survive for say at least six months;
- devices will then operate in sleep/low energy modes and this must be considered in schematics;
- in detail, MPU6050 interrupt pin awakens the Mcu when a motion is detected;
- otherwise, Mcu awakens once every day or so, reads sensors data, sends data via Wifi to master, or, if masters, collects data and sends data via GSM to the internet;
- I am not sure which battery pack/jacks/fuse... are best suited, so I appreciated suggestions;
- batteries must be rechargeable;
- battery level must be read by microcontroller;
- as a main microcontroller I would use an ESP8266 12 (Wizzy, NodeMcu);
- both slaves and master must consider a MPU6050 (GY520) and a HX711 with pins exposed for easy and connections;
- physical dimensions: height=max 2cm; width=about 20-25cm; depth=2-4cm, battery included (PCB will be boxed in a case for outdoor use);
- MPU6050 must be connected to the PCB via a cheap connector only (external component);
- all other components are on the PCB;
- SIM slot, HX711 external connections, MPU6050 plug and battery lid must be all exposed on only one side of the PCB with easy access by the user;
- I do not know which GSM+GPS module be the best bet (price, availability, easy of use) so I would be glad to receive proposals (till now I encountered most of the problems with these modules);
- I already planned some schematics I could discuss later on chat, if that helps.
Since it uses EM devices as WiFi and GSM, layout and components must take in account to be compatible with European Union certifications and standards (RoHS, trace width,...).
- PCB layout files, in KiCad format with all components;
- BOM with links to best price resellers;
- suggestion for PCB and assembled PCB (APCB) producer services comparison (in Europe as in Far East):
what I want to do is to try to let the PCB be produced, and solder components by myself (if feasible) or at worst let the PCB be assembled and delivered.
I would like to start producing a very small batch (eg: 1-3 pieces: 1-2 slave + 1 master), test them on the field, then go on more consistend batches.
Thank You for Your support!