wireless charger for an electronic grain humidity datalogger in a coffee solar dryer

Drying is a very important process for obtaining a high quality, speciality  coffee; an electronic grain datalogger is necesary for measuring and control temperature and relative humidity conditions in a solar driyer  (wich is the best way to obtain a great coffee flavor, aroma and fragancy).

When the coffee grain is in the solar driyer (for almost 15 days), is necesary to have the best clean conditions, so is not good that people touch grains or  put external things than can affect the process; coffee drying process begins with humidity from 50% to 60% and ends in 10% or 12% wich is the humidity in a export quality coffee.

There is a method for monitoring on-line grain humidity, called “Gravimet”, using the change of weight of 200g of grain in the begin of the process until it go down to 105g.

The idea is to develop an electronic device to monitor the weight of the grain helping coffee producers to know when it is ready; the device power is a li-ion batery pack and use a wireless power system to charge it without using cables or manipulate the coffee.