Files
picar/control/gpio/vehicle.py
2020-04-15 20:50:30 +09:30

84 lines
2.4 KiB
Python

from gpiozero import Servo, Device
from gpiozero.pins.pigpio import PiGPIOFactory
import subprocess
def _safely_set_servo_value(servo, value):
try:
if value < -1 or value > 1:
print("Not setting throttle, invalid value set.")
return False
servo.value = value
except TypeError:
print("throttle should be a number, preferably a float.")
return False
return True
def _is_pin_valid(pin):
if isinstance(pin, int):
if pin < 2 or pin > 21:
print("Invalid GPIO pin")
return False
return True
else:
print("Value must be an int.")
return False
# TODO: Allow a vector to be set to change the throttle/steering, for vehicles that don't use
# two servos for controls (e.g. drone, dog)
class Vehicle:
def __init__(self, motor_pin=19, servo_pin=18):
subprocess.call(['sudo', 'pigpiod'])
Device.pin_factory = PiGPIOFactory()
print('Using pin factory:')
print(Device.pin_factory)
self.motor_pin = motor_pin
self.steering_pin = servo_pin
self.initialise_motor()
def initialise_motor(self):
self._motor_servo = Servo(
self._motor_pin, pin_factory=Device.pin_factory)
self._steering_servo = Servo(self._steering_pin, pin_factory=Device.pin_factory)
@property
def throttle(self):
return self._motor_servo.value
@throttle.setter
def throttle(self, value):
_safely_set_servo_value(self._motor_servo, value)
@property
def steering(self):
return self._motor_servo.value
@steering.setter
def steering(self, value):
_safely_set_servo_value(self._motor_servo, value)
@property
def motor_pin(self):
return self._motor_pin
@motor_pin.setter
def motor_pin(self, value):
# TODO: Reinitialise the servo when the pin changes, or discard this method
# (probably don't want to allow pin changes whilst the device is in use anyway)
self._motor_pin = value if _is_pin_valid(value) else self._motor_pin
@property
def steering_pin(self):
return self._steering_pin
@steering_pin.setter
def steering_pin(self, value):
self._steering_pin = value if _is_pin_valid(value) else self._steering_pin
def stop(self):
self.throttle = 0
self.steering = 0
def change_with_vector(self, vector):
pass