Current chapter 11

ch-11/1-measuring-wheel-speeds/code.py

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+import asyncio
+import robot
+
+class Settings:
+  speed = 0.7
+  time_interval = 0.2
+
+async def motor_speed_loop():
+  left_last, right_last = robot.left_encoder.read(), robot.right_encoder.read()
+  while True:
+    await asyncio.sleep(Settings.time_interval)
+    left_new, right_new = robot.left_encoder.read(), robot.right_encoder.read()
+    left_speed = robot.ticks_to_m * (left_new - left_last) / Settings.time_interval
+    left_last = left_new
+    right_speed = robot.ticks_to_m * (right_new - right_last) / Settings.time_interval
+    right_last = right_new
+    robot.uart.write(f"{left_speed:.3f},{right_speed:.3f},0\n".encode())
+
+async def stop_motors_after(seconds):
+  await asyncio.sleep(seconds)
+  robot.stop()
+
+async def command_handler():
+  while True:
+    if robot.uart.in_waiting:
+      command = robot.uart.readline().decode().strip()
+      if command.startswith("M"):
+        Settings.speed = float(command[1:])
+      elif command.startswith("T"):
+        Settings.time_interval = float(command[1:])
+      elif command == "O":
+        robot.stop()
+      elif command.startswith("O"):
+        await asyncio.sleep(5)
+        asyncio.create_task(stop_motors_after(float(command[1:])))
+        robot.set_left(Settings.speed)
+        robot.set_right(Settings.speed)
+      elif command.startswith("?"):
+        robot.uart.write(f"M{Settings.speed:.1f}\n".encode())
+        robot.uart.write(f"T{Settings.time_interval:.1f}\n".encode())
+        await asyncio.sleep(3)
+    await asyncio.sleep(0)
+
+try:
+  asyncio.create_task(motor_speed_loop())
+  asyncio.run(command_handler())
+finally:
+  robot.stop()