obstacle - Obstacle and robot definition

class gym_ultrasonic.envs.obstacle.Obstacle(position, width, height, angle=0)

Bases: object

A static rectangular obstacle.

property polygon

Returns

Polygon

Minimum rotated bounding box polygon.

get_polygon_parallel_coords(self)

Returns

np.ndarray

Clock-wise vertices of the bounding box polygon, parallel to the world axes.

set_position(self, position)

Sets the object global position.

Parameters

position: List[float]

Obstacle center position in world coordinates, (x, y).

extra_repr(self)

class gym_ultrasonic.envs.obstacle.Servo(width, height, sonar_direction_angles=(0, ), angle_range=(-0.5235987755982988, 0.5235987755982988), angular_vel=0)

Bases: gym_ultrasonic.envs.obstacle.Obstacle

Servo that holds sonar(s) on board. Servo has only one function - rotate the sonar(s).

property sonar_angles_world

rotate(self, sim_time=None, angle_turn=None)

Rotates the servo.

Parameters

sim_time: float

Simulation time step, sec.

angle_turn: float

Angle to rotate the servo. If set to None, it’s calculated by the time spent, multiplied by the angular velocity.

reset(self)

Resets the servo.

extra_repr(self)

class gym_ultrasonic.envs.obstacle.Robot(width, height, sonar_direction_angles=(0, ), sensor_max_dist=2000)

Bases: gym_ultrasonic.envs.obstacle.Obstacle

Robot with a mounted servo and ultrasonic range sensor.

property servo_shift

Returns

float

Shift of the servo along robot’s main axis, mm

property n_sonars

Returns

int

Num. of sonars on board.

move_forward(self, move_step)

Parameters

move_step: float

Move step, mm.

diffdrive(self, vel_left, vel_right, sim_time)

Differential drive. Adapted from http://ais.informatik.uni-freiburg.de/teaching/ss17/robotics/exercises/solutions/03/sheet03sol.pdf

Parameters

vel_left: float

Left wheel tangential speed, mm / sec.

vel_right: float

Right wheel tangential speed, mm / sec.

sim_time: float

Simulation time step, sec.

Returns

move_step: float

Performed move step in mm along robot’s main axis.

angle_rotate: float

Performed rotation in radians.

trajectory: LineString

Trajectory of this step.

turn(self, angle_step)

Parameters

angle_step: float

CCW angle turn in radians.

collision(self, obj)

Parameters

obj: Obstacle or List[Obstacle]

An obstacle(s) to check for a collision.

Returns

bool

If robot’s minimum rotated bounding box collides with an obstacle(s).

property direction_vector

Returns

np.ndarray

Robot’s direction vector, (x, y)

property servo_position

Returns

np.ndarray

World coordinates of Servo with embedded Ultrasonic sensor, (x, y)

ray_cast(self, obstacles)

Casts a ray along servo sensor direction and checks if there an intersection with obstacles. Simulates Ultrasonic range sonar, mounted on top of the servo, in a real robot.

Parameters

obstacles: List[Obstacle]

List of obstacles in the scene.

Returns

min_dist: List[float]

Min dist to an obstacle. If no obstacle is found at the ray intersection, max_dist is returned.

intersection_xy: List[np.ndarray]

X and Y of the intersection point with an obstacle.

reset(self, box)

Sets the current position to a random point from a box.

Parameters

box: Box

Allowed box space to sample a point from.

extra_repr(self)