Added get_speed() function

mappingbot/encoder.py

 import RPi.GPIO as GPIO
 import time
+import math
 
 GPIO.setmode(GPIO.BCM)
 print(GPIO.VERSION)
 
+
 class Encoder:
-    
+
     def __init__(self, name, encoder_pin: int):
-        global pulse_count
+        global pulse_count, start_time, time_passed, old_time_passed, old_pulse_count
         self.name = name
         self.encoder_pin = encoder_pin
         pulse_count = 0
+        start_time = time.time()
+        time_passed = 0
+        old_time_passed = 0
+        old_pulse_count = 0
 
         GPIO.setup(self.encoder_pin, GPIO.IN, GPIO.PUD_DOWN)
-        
+
     def callback_encoder(self, channel):
-        global pulse_count
+        global pulse_count, start_time, time_passed
+        time_passed = time.time() - start_time
         pulse_count += 1
 
     def get_pulse_count(self) -> int:
         global pulse_count
         return pulse_count
 
+    def get_average_pulse_speed(self) -> float:
+        global time_passed, pulse_count
+        if time_passed != 0:
+            return pulse_count / time_passed
+        else:
+            return 0
+
     def reset_pulse_count(self):
-        global pulse_count
+        global pulse_count, time_passed, start_time
         pulse_count = 0
+        time_passed = 0
+        start_time = time.time()
+
+    def get_current_pulse_speed(self) -> float:
+        global pulse_count, time_passed, old_time_passed, old_pulse_count
+        print("time " + str(time_passed))
+        if (time_passed - old_time_passed):
+            speed = (pulse_count - old_pulse_count) / (time_passed - old_time_passed)
+        else:
+            speed = 0
+        old_pulse_count = pulse_count
+        old_time_passed = time_passed
+        return speed
+
+    def get_speed(self) -> float:
+        pulse_per_second = self.get_current_pulse_speed()
+        return pulse_per_second * (6 * 2 * math.pi) / 40
 
     def init_callback(self):
-        GPIO.add_event_detect(self.encoder_pin, GPIO.BOTH, callback = self.callback_encoder, bouncetime = 10)
+        GPIO.add_event_detect(self.encoder_pin, GPIO.BOTH, callback=self.callback_encoder, bouncetime=10)
 
 
 try:
@@ -35,6 +66,7 @@ try:
     encoder1.init_callback()
     while True:
         print(encoder1.get_pulse_count())
+        print(encoder1.get_speed())
         time.sleep(1)
 except KeyboardInterrupt:  # Exit by pressing CTRL + C
     GPIO.cleanup()