Imagine a two wheeled robot. The robot has two DC motors with rated speed of 60 rpm. The distance between the two wheels is around 20 cm. What should be the operating speeds of both the motors (outer and inner), such that the inner wheel covers a circle of 40 cm radius (as shown) in fastest possible time? How will you achieve the speeds of the two motors in here using the digital output pins of a microcontroller?
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Calculate the time the outer wheel needs to cover a circular path of 60cm radius at its maximum speed (60 rpm). Then use the calculated time to find the required speed of the inner wheel as to cover a circular path of 40cm radius. The speed of the wheels can be controlled with PWM.