I have been trying out a new idea using a motor and propeller from a quad copter which is powered by USB, the motor and propeller I have, do not produce enough power(lift).
1. ... I need to source a powerful fan, no bigger than 2inch (50mm)
needs to be powered by a USB.
2. once we have a fan selected,
I will need to run the fan at full power,
every 20seconds the fan should slow down or stop just for a second,
then resume full speed again.