carla/PythonAPI/examples/vehicle_physics.py

145 lines
4.6 KiB
Python

#!/usr/bin/env python
# Copyright (c) 2020 Computer Vision Center (CVC) at the Universitat Autonoma de
# Barcelona (UAB).
#
# This work is licensed under the terms of the MIT license.
# For a copy, see <https://opensource.org/licenses/MIT>.
"""
Vehicle physics example for CARLA
Small example that shows the effect of different impulse and force aplication
methods to a vehicle.
"""
import glob
import os
import sys
import argparse
try:
sys.path.append(glob.glob('../carla/dist/carla-*%d.%d-%s.egg' % (
sys.version_info.major,
sys.version_info.minor,
'win-amd64' if os.name == 'nt' else 'linux-x86_64'))[0])
except IndexError:
pass
import carla
def print_step_info(world, vehicle):
snapshot = world.get_snapshot()
print("%d %06.03f %+8.03f %+8.03f %+8.03f %+8.03f %+8.03f %+8.03f %+8.03f %+8.03f %+8.03f" %
(snapshot.frame, snapshot.timestamp.elapsed_seconds, \
vehicle.get_acceleration().x, vehicle.get_acceleration().y, vehicle.get_acceleration().z, \
vehicle.get_velocity().x, vehicle.get_velocity().y, vehicle.get_velocity().z, \
vehicle.get_location().x, vehicle.get_location().y, vehicle.get_location().z))
def wait(world, frames=100):
for i in range(0, frames):
world.tick()
def main(arg):
"""Main function of the script"""
client = carla.Client(arg.host, arg.port)
client.set_timeout(2.0)
world = client.get_world()
try:
# Setting the world and the spawn properties
original_settings = world.get_settings()
settings = world.get_settings()
delta = 0.1
settings.fixed_delta_seconds = delta
settings.synchronous_mode = True
world.apply_settings(settings)
blueprint_library = world.get_blueprint_library()
vehicle_bp = blueprint_library.filter(arg.filter)[0]
vehicle_transform = world.get_map().get_spawn_points()[0]
vehicle_transform.location.z += 3
vehicle = world.spawn_actor(vehicle_bp, vehicle_transform)
physics_vehicle = vehicle.get_physics_control()
car_mass = physics_vehicle.mass
spectator_transform = carla.Transform(vehicle_transform.location, vehicle_transform.rotation)
spectator_transform.location += vehicle_transform.get_forward_vector() * 20
spectator_transform.rotation.yaw += 180
spectator = world.get_spectator()
spectator.set_transform(spectator_transform)
# We let the vehicle stabilize and save the transform to reset it after each test.
wait(world)
vehicle.set_target_velocity(carla.Vector3D(0, 0, 0))
vehicle_transform = vehicle.get_transform()
wait(world)
# Impulse/Force at the center of mass of the object
impulse = 10 * car_mass
print("# Adding an Impulse of %f N s" % impulse)
vehicle.add_impulse(carla.Vector3D(0, 0, impulse))
wait(world)
vehicle.set_transform(vehicle_transform)
vehicle.set_target_velocity(carla.Vector3D(0, 0, 0))
wait(world)
print("# Adding a Force of %f N" % (impulse / delta))
# The add_force method should not be use for instantaneous forces like this one,
# it is more useful for constant or variable forces acting in a finite amount of time.
# In this script it is done with the proper scaling to show the equivalence
# between the add_impulse and add_force methods.
# As in this case the force is going to be applied during the whole step dt=delta
# a force more or less equivalent is impulse / delta.
vehicle.add_force(carla.Vector3D(0, 0, impulse / delta))
wait(world)
vehicle.set_transform(vehicle_transform)
vehicle.set_target_velocity(carla.Vector3D(0, 0, 0))
wait(world)
wait(world, 500)
finally:
world.apply_settings(original_settings)
vehicle.destroy()
if __name__ == "__main__":
argparser = argparse.ArgumentParser(
description=__doc__)
argparser.add_argument(
'--host',
metavar='H',
default='localhost',
help='IP of the host CARLA Simulator (default: localhost)')
argparser.add_argument(
'-p', '--port',
metavar='P',
default=2000,
type=int,
help='TCP port of CARLA Simulator (default: 2000)')
argparser.add_argument(
'--filter',
metavar='PATTERN',
default='model3',
help='actor filter (default: "vehicle.*")')
args = argparser.parse_args()
try:
main(args)
except KeyboardInterrupt:
print(' - Exited by user.')