2 different design of an electric generator using 3D Autocad

I need 2 different creative electric generators can operate by sand energy consists of a hollow-ended cardboard box with an axis (nail) through the center, copper wound around the axis and magnets clamped around the axis, when the axis and magnets are spun fast (bulb, swith or motor) is activated. the generators should be minimum cost not more than 15 Dollars, it is expected that the voltage produced by several volts, and the most important that the generators capable to convert AC to DC (Direct Current)