Files
Gymnasium/gym/envs/mujoco/thrower.py
2021-07-28 20:26:34 -04:00

68 lines
2.1 KiB
Python

import numpy as np
from gym import utils
from gym.envs.mujoco import mujoco_env
class ThrowerEnv(mujoco_env.MujocoEnv, utils.EzPickle):
def __init__(self):
utils.EzPickle.__init__(self)
self._ball_hit_ground = False
self._ball_hit_location = None
mujoco_env.MujocoEnv.__init__(self, "thrower.xml", 5)
def step(self, a):
ball_xy = self.get_body_com("ball")[:2]
goal_xy = self.get_body_com("goal")[:2]
if not self._ball_hit_ground and self.get_body_com("ball")[2] < -0.25:
self._ball_hit_ground = True
self._ball_hit_location = self.get_body_com("ball")
if self._ball_hit_ground:
ball_hit_xy = self._ball_hit_location[:2]
reward_dist = -np.linalg.norm(ball_hit_xy - goal_xy)
else:
reward_dist = -np.linalg.norm(ball_xy - goal_xy)
reward_ctrl = -np.square(a).sum()
reward = reward_dist + 0.002 * reward_ctrl
self.do_simulation(a, self.frame_skip)
ob = self._get_obs()
done = False
return ob, reward, done, dict(reward_dist=reward_dist, reward_ctrl=reward_ctrl)
def viewer_setup(self):
self.viewer.cam.trackbodyid = 0
self.viewer.cam.distance = 4.0
def reset_model(self):
self._ball_hit_ground = False
self._ball_hit_location = None
qpos = self.init_qpos
self.goal = np.array(
[
self.np_random.uniform(low=-0.3, high=0.3),
self.np_random.uniform(low=-0.3, high=0.3),
]
)
qpos[-9:-7] = self.goal
qvel = self.init_qvel + self.np_random.uniform(
low=-0.005, high=0.005, size=self.model.nv
)
qvel[7:] = 0
self.set_state(qpos, qvel)
return self._get_obs()
def _get_obs(self):
return np.concatenate(
[
self.sim.data.qpos.flat[:7],
self.sim.data.qvel.flat[:7],
self.get_body_com("r_wrist_roll_link"),
self.get_body_com("ball"),
self.get_body_com("goal"),
]
)