SunFounder PiCar-4WD, Manual

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fc . turn_right ( Track_line_speed )
if __name__ == '__main__' :
while True :
Track_line ()
follow.py
In the code, the ultrasonic module will take sample to form an array containing 11 elements; the module
detects once every 18° and puts the distance state (0，1，2) of every angle into the array. If there is
something obstructive at the right front, the detection value is [22222211122].
The array takes the 2 as a delimiter to divide the array anew. The examples above will be divided into
several null elements and a [111]- value element.
The corresponding angular range of the element with a value [111] is 108°~144° (0°+18°*6=108°, 0°+18°
*8=144°), and the car will turn its angle into a median 126°（（144+108）/2）
Judge the distance, and keep the car away from the object about 10cm.
Note: Refer to 「scan_step()」and「get_status_at()」in 「_init_.py」to get more details about radar sampling
and the distance state judgement.
import picar_4wd as fc
speed = 30
def main ():
while True :
scan_list = fc . scan_step ( 23 )
if not scan_list :