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Figure .3.2.4 Schematic Diagram of Motor Drive
Four DC motors with high power L298N drive enable "Hummer-Bot" to run faster than conventional
two-wheel car, the acceleration time is shorter and the structure is more stable. However, in the actual
application, we need to adjust the speed of the car because of environmental or other factors, yet this does not
affect the forward, backward, stop, flexible steering of the car, so we use PWM to control the speed of the
motor(Note: PWM is a way to simulate the simulation output via square waves with different duty cycles.),
Arduino PWM port outputs a series of square waves with fixed frequency, the power and current of the motor
can be amplified after receiving the signal, thereby changing the motor's speed. The speed coordination of
two motors on the right and left wheels can achieve the forward, backward, turning and other functions of the
car. Figure 2.4.5 shows the sequence diagram of PWM duty cycles.
Figure .3.2.5 Sequence Diagram of PWM Duty Cycles
In Arduino, analog voltage can't be output, only 0 or 5V digital voltage value, we can use high
resolution counter and the duty cycles of the square wave modulation method to encode a specific level of
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