Schematic of driving circuit
The whole driving circuit consist of four parts.
1. Lithium battery (can supply power of 3.7 Vpp)
2. Boost circuit module (can increase voltage from 3.7 to 5 Vpp)
3. Arduino board (has a USB port, can communicate with the computer by writing codes）
4. Vibration motors (can connect to four PWM output and by activated.
Actual driving circuit
The positive wire of motors are connected to the PWM outputs. The ground wire of motors are connected to the Gnd pin of the Arduino. Thus, by setting different values for each motors through programming, the motors can be activated, respectively and the vibration amplitude can be adjusted.
Demonstration of activating motors
By setting the same value for each PWM output through programming, four motors can be activated at the same time.
By setting the value and delay time for each PWM output in turn through programming, four motors can be activated in turn.
