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Experiment 1: the initial voltage was kept constant while varying the pwm signal. See figure experiment1.png. The speed always reaches a peak and then decrease to a steady state value. The second run starts more or less from the steady state value. The PWM does not seem to affect neither the time constant nor the steady state value that is more or less always 200 mm/s below the peak.
Experiment 2: the pwm was kept constant while varying the initial voltage. The car is run only the first time.
Experiment 3: the car is run 3 times in a row to check if the third time the speed dynamics changes again.
Experiment 5: the car is left turned on for 25 minutes before running to check if the capacitor gets discharged even if the car is not running.
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