updates

fancy_gym/black_box/black_box_wrapper.py

@@ -23,7 +23,7 @@ class BlackBoxWrapper(gym.ObservationWrapper):
                  replanning_schedule: Optional[
                      Callable[[np.ndarray, np.ndarray, np.ndarray, np.ndarray, int], bool]] = None,
                  reward_aggregation: Callable[[np.ndarray], float] = np.sum,
-                 max_planning_times: int = 1,
+                 max_planning_times = None,
                  desired_conditioning: bool = False
                  ):
         """
@@ -163,8 +163,9 @@ class BlackBoxWrapper(gym.ObservationWrapper):
         # action = np.concatenate((basis_weights, goal_weights), axis=1).flatten()
 
         # TODO remove this part, right now only needed for beer pong
-        mp_params, env_spec_params = self.env.episode_callback(action, self.traj_gen)
+        # mp_params, env_spec_params, proceed = self.env.episode_callback(action, self.traj_gen)
-        position, velocity = self.get_trajectory(mp_params)
+        position, velocity = self.get_trajectory(action)
+        traj_is_valid = self.env.episode_callback(action, position, velocity)
 
         trajectory_length = len(position)
         rewards = np.zeros(shape=(trajectory_length,))
@@ -176,6 +177,13 @@ class BlackBoxWrapper(gym.ObservationWrapper):
         infos = dict()
         done = False
 
+        if self.verbose >= 2:
+            desired_pos_traj = []
+            desired_vel_traj = []
+            pos_traj = []
+            vel_traj = []
+
+        if traj_is_valid:
             self.plan_counts += 1
             for t, (pos, vel) in enumerate(zip(position, velocity)):
                 step_action = self.tracking_controller.get_action(pos, vel, self.current_pos, self.current_vel)
@@ -192,14 +200,20 @@ class BlackBoxWrapper(gym.ObservationWrapper):
                     elems[t] = v
                     infos[k] = elems
 
+                if self.verbose >= 2:
+                    desired_pos_traj.append(pos)
+                    desired_vel_traj.append(vel)
+                    pos_traj.append(self.current_pos)
+                    vel_traj.append(self.current_vel)
+
                 if self.render_kwargs:
                     self.env.render(**self.render_kwargs)
 
                 if done or self.replanning_schedule(self.current_pos, self.current_vel, obs, c_action,
                                                     t + 1 + self.current_traj_steps):
 
-                if self.max_planning_times is not None and self.plan_counts >= self.max_planning_times:
+                    # if self.max_planning_times is not None and self.plan_counts >= self.max_planning_times:
-                    continue
+                    #     continue
 
                     self.condition_pos = pos if self.desired_conditioning else self.current_pos
                     self.condition_vel = vel if self.desired_conditioning else self.current_vel
@@ -217,11 +231,17 @@ class BlackBoxWrapper(gym.ObservationWrapper):
                 infos['step_actions'] = actions[:t + 1]
                 infos['step_observations'] = observations[:t + 1]
                 infos['step_rewards'] = rewards[:t + 1]
+                infos['desired_pos_traj'] = np.array(desired_pos_traj)
+                infos['desired_vel_traj'] = np.array(desired_vel_traj)
+                infos['pos_traj'] = np.array(pos_traj)
+                infos['vel_traj'] = np.array(vel_traj)
 
             infos['trajectory_length'] = t + 1
             trajectory_return = self.reward_aggregation(rewards[:t + 1])
             return self.observation(obs), trajectory_return, done, infos
-
+        else:
+            obs, trajectory_return, done, infos = self.env.invalid_traj_callback(action, position, velocity)
+            return self.observation(obs), trajectory_return, done, infos
     def render(self, **kwargs):
         """Only set render options here, such that they can be used during the rollout.
         This only needs to be called once"""

fancy_gym/black_box/raw_interface_wrapper.py

@@ -52,8 +52,7 @@ class RawInterfaceWrapper(gym.Wrapper):
         """
         return self.env.dt
 
-    def episode_callback(self, action: np.ndarray, traj_gen: MPInterface) -> Tuple[
+    def episode_callback(self, action: np.ndarray, pos_traj: np.ndarray, vel_traj: np.array) -> Tuple[bool]:
-        np.ndarray, Union[np.ndarray, None]]:
         """
         Used to extract the parameters for the movement primitive and other parameters from an action array which might
         include other actions like ball releasing time for the beer pong environment.
@@ -65,4 +64,11 @@ class RawInterfaceWrapper(gym.Wrapper):
         Returns:
             Tuple: mp_arguments and other arguments
         """
-        return action, None
+        return True
+
+    def invalid_traj_callback(self, action: np.ndarray, pos_traj: np.ndarray, vel_traj: np.ndarray) -> Tuple[np.ndarray, float, bool, dict]:
+        """
+        Used to return a fake return from the environment if the desired trajectory is invalid.
+        """
+        obs = np.zeros(1)
+        return obs, 0, True, {}

fancy_gym/envs/__init__.py

@@ -28,7 +28,9 @@ DEFAULT_BB_DICT_ProMP = {
         'trajectory_generator_type': 'promp'
     },
     "phase_generator_kwargs": {
-        'phase_generator_type': 'linear'
+        'phase_generator_type': 'linear',
+        'learn_tau': False,
+        'learn_delay': False,
     },
     "controller_kwargs": {
         'controller_type': 'motor',
@@ -40,6 +42,8 @@ DEFAULT_BB_DICT_ProMP = {
         'num_basis': 5,
         'num_basis_zero_start': 1,
         'basis_bandwidth_factor': 3.0,
+    },
+    "black_box_kwargs": {
     }
 }
 
@@ -245,6 +249,18 @@ register(
     max_episode_steps=FIXED_RELEASE_STEP,
 )
 
+# Table Tennis environments
+for ctxt_dim in [2, 4]:
+    register(
+        id='TableTennis{}D-v0'.format(ctxt_dim),
+        entry_point='fancy_gym.envs.mujoco:TableTennisEnv',
+        max_episode_steps=350,
+        kwargs={
+            "ctxt_dim": ctxt_dim,
+            'frame_skip': 4
+        }
+    )
+
 # movement Primitive Environments
 
 ## Simple Reacher
@@ -515,6 +531,29 @@ for _v in _versions:
         kwargs=kwargs_dict_box_pushing_prodmp
     )
     ALL_FANCY_MOVEMENT_PRIMITIVE_ENVIRONMENTS["ProDMP"].append(_env_id)
+
+## Table Tennis
+_versions = ['TableTennis2D-v0', 'TableTennis4D-v0']
+for _v in _versions:
+    _name = _v.split("-")
+    _env_id = f'{_name[0]}ProMP-{_name[1]}'
+    kwargs_dict_tt_promp = deepcopy(DEFAULT_BB_DICT_ProMP)
+    kwargs_dict_tt_promp['wrappers'].append(mujoco.table_tennis.MPWrapper)
+    kwargs_dict_tt_promp['name'] = _v
+    kwargs_dict_tt_promp['controller_kwargs']['p_gains'] = 0.5 * np.array([1.0, 4.0, 2.0, 4.0, 1.0, 4.0, 1.0])
+    kwargs_dict_tt_promp['controller_kwargs']['d_gains'] = 0.5 * np.array([0.1, 0.4, 0.2, 0.4, 0.1, 0.4, 0.1])
+    kwargs_dict_tt_promp['phase_generator_kwargs']['learn_tau'] = True
+    kwargs_dict_tt_promp['phase_generator_kwargs']['learn_delay'] = True
+    kwargs_dict_tt_promp['basis_generator_kwargs']['num_basis'] = 3
+    kwargs_dict_tt_promp['basis_generator_kwargs']['num_basis_zero_start'] = 2
+    kwargs_dict_tt_promp['black_box_kwargs']['duration'] = 2.
+    kwargs_dict_tt_promp['black_box_kwargs']['verbose'] = 2
+    register(
+        id=_env_id,
+        entry_point='fancy_gym.utils.make_env_helpers:make_bb_env_helper',
+        kwargs=kwargs_dict_tt_promp
+    )
+    ALL_FANCY_MOVEMENT_PRIMITIVE_ENVIRONMENTS["ProMP"].append(_env_id)
 #
 # ## Walker2DJump
 # _versions = ['Walker2DJump-v0']

fancy_gym/envs/mujoco/__init__.py

@@ -8,3 +8,4 @@ from .hopper_throw.hopper_throw_in_basket import HopperThrowInBasketEnv
 from .reacher.reacher import ReacherEnv
 from .walker_2d_jump.walker_2d_jump import Walker2dJumpEnv
 from .box_pushing.box_pushing_env import BoxPushingDense, BoxPushingTemporalSparse, BoxPushingTemporalSpatialSparse
+from .table_tennis.table_tennis_env import TableTennisEnv

fancy_gym/envs/mujoco/beerpong/mp_wrapper.py

@@ -28,10 +28,10 @@ class MPWrapper(RawInterfaceWrapper):
         return self.data.qvel[0:7].copy()
 
     # TODO: Fix this
-    def episode_callback(self, action: np.ndarray, mp) -> Tuple[np.ndarray, Union[np.ndarray, None]]:
+    def episode_callback(self, action: np.ndarray, mp) -> Tuple[np.ndarray, Union[np.ndarray, None], bool]:
         if mp.learn_tau:
             self.release_step = action[0] / self.dt  # Tau value
-        return action, None
+        return action, None, True
 
     def set_context(self, context):
         xyz = np.zeros(3)

fancy_gym/envs/mujoco/table_tennis/mp_wrapper.py

@@ -3,6 +3,7 @@ from typing import Union, Tuple
 import numpy as np
 
 from fancy_gym.black_box.raw_interface_wrapper import RawInterfaceWrapper
+from fancy_gym.envs.mujoco.table_tennis.table_tennis_utils import jnt_pos_low, jnt_pos_high, delay_bound, tau_bound
 
 
 class MPWrapper(RawInterfaceWrapper):
@@ -13,10 +14,8 @@ class MPWrapper(RawInterfaceWrapper):
         return np.hstack([
             [False] * 7,  # joints position
             [False] * 7,  # joints velocity
-            [False] * 3,  # position of box
+            [False] * 3,  # position ball
-            [False] * 4,  # orientation of box
+            [True] * 2,  # target landing position
-            [True] * 3,  # position of target
-            [True] * 4,  # orientation of target
             # [True] * 1,  # time
         ])
 
@@ -27,3 +26,27 @@ class MPWrapper(RawInterfaceWrapper):
     @property
     def current_vel(self) -> Union[float, int, np.ndarray, Tuple]:
         return self.data.qvel[:7].copy()
+
+    def episode_callback(self, action, pos_traj, vel_traj):
+        time_invalid = action[0] > tau_bound[1] or action[0] < tau_bound[0] \
+                     or action[1] > delay_bound[1] or action[1] < delay_bound[0]
+        if time_invalid or np.any(pos_traj > jnt_pos_high) or np.any(pos_traj < jnt_pos_low):
+            return False
+        return True
+
+    def invalid_traj_callback(self, action, pos_traj: np.ndarray, vel_traj: np.ndarray) \
+            -> Tuple[np.ndarray, float, bool, dict]:
+        tau_invalid_penalty = np.max([0, action[0] - tau_bound[1]]) + np.max([0, tau_bound[0] - action[0]])
+        delay_invalid_penalty = np.max([0, action[1] - delay_bound[1]]) + np.max([0, delay_bound[0] - action[1]])
+        violate_high_bound_error = np.sum(np.maximum(pos_traj - jnt_pos_high, 0))
+        violate_low_bound_error = np.sum(np.maximum(jnt_pos_low - pos_traj, 0))
+        invalid_penalty = tau_invalid_penalty + delay_invalid_penalty + \
+                          violate_high_bound_error + violate_low_bound_error
+        return self.get_obs(), -invalid_penalty, True, {
+        "hit_ball": [False],
+        "ball_returned_success": [False],
+        "land_dist_error": [10.],
+        "is_success": [False],
+        'trajectory_length': 1,
+        "num_steps": [1]
+        }

fancy_gym/envs/mujoco/table_tennis/table_tennis_env.py

@@ -4,6 +4,8 @@ import numpy as np
 from gym import utils, spaces
 from gym.envs.mujoco import MujocoEnv
 
+from fancy_gym.envs.mujoco.table_tennis.table_tennis_utils import check_init_state_validity, magnus_force
+
 import mujoco
 
 MAX_EPISODE_STEPS_TABLE_TENNIS = 250
@@ -22,10 +24,23 @@ class TableTennisEnv(MujocoEnv, utils.EzPickle):
         utils.EzPickle.__init__(**locals())
         self._steps = 0
 
-        self.hit_ball = False
+        self._hit_ball = False
-        self.ball_land_on_table = False
+        self._ball_land_on_table = False
+        self._ball_contact_after_hit = False
+        self._ball_return_success = False
+        self._ball_landing_pos = None
+        self._init_ball_state = None
+        self._episode_end = False
+
         self._id_set = False
+
+        # reward calculation
         self.ball_landing_pos = None
+        self._goal_pos = np.zeros(2)
+        self._ball_traj = []
+        self._racket_traj = []
+
+
         MujocoEnv.__init__(self,
                            model_path=os.path.join(os.path.dirname(__file__), "assets", "xml", "table_tennis_env.xml"),
                            frame_skip=frame_skip,
@@ -40,11 +55,11 @@ class TableTennisEnv(MujocoEnv, utils.EzPickle):
         self.action_space = spaces.Box(low=-1, high=1, shape=(7,), dtype=np.float32)
 
     def _set_ids(self):
-        self._floor_contact_id = self.model.geom("floor").bodyid[0]
+        self._floor_contact_id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_GEOM, "floor")
-        self._ball_contact_id = self.model.geom("target_ball_contact").bodyid[0]
+        self._ball_contact_id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_GEOM, "target_ball_contact")
-        self._bat_front_id = self.model.geom("bat").bodyid[0]
+        self._bat_front_id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_GEOM, "bat")
-        self._bat_back_id = self.model.geom("bat_back").bodyid[0]
+        self._bat_back_id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_GEOM, "bat_back")
-        self._table_contact_id = self.model.geom("table_tennis_table").bodyid[0]
+        self._table_contact_id = mujoco.mj_name2id(self.model, mujoco.mjtObj.mjOBJ_GEOM, "table_tennis_table")
         self._id_set = True
 
     def step(self, action):
@@ -53,40 +68,55 @@ class TableTennisEnv(MujocoEnv, utils.EzPickle):
 
         unstable_simulation = False
 
-        done = False
-
         for _ in range(self.frame_skip):
             try:
-                self.do_simulation(action, self.frame_skip)
+                self.do_simulation(action, 1)
             except Exception as e:
                 print("Simulation get unstable return with MujocoException: ", e)
                 unstable_simulation = True
+                self._episode_end = True
+                break
 
-            if not self.hit_ball:
+            if not self._hit_ball:
-                self.hit_ball = self._contact_checker(self._ball_contact_id, self._bat_front_id) or \
+                self._hit_ball = self._contact_checker(self._ball_contact_id, self._bat_front_id) or \
                                 self._contact_checker(self._ball_contact_id, self._bat_back_id)
-                if not self.hit_ball:
+                if not self._hit_ball:
                     ball_land_on_floor_no_hit = self._contact_checker(self._ball_contact_id, self._floor_contact_id)
                     if ball_land_on_floor_no_hit:
-                        self.ball_landing_pos = self.data.body("target_ball").xpos.copy()
+                        self._ball_landing_pos = self.data.body("target_ball").xpos.copy()
-                        done = True
+                        self._episode_end = True
-            if self.hit_ball and not self.ball_contact_after_hit:
+            if self._hit_ball and not self._ball_contact_after_hit:
-                if not self.ball_contact_after_hit:
+                if not self._ball_contact_after_hit:
                     if self._contact_checker(self._ball_contact_id, self._floor_contact_id):  # first check contact with floor
-                        self.ball_contact_after_hit = True
+                        self._ball_contact_after_hit = True
-                        self.ball_landing_pos = self.sim.data.geom("target_ball_contact").xpos.copy()
+                        self._ball_landing_pos = self.data.geom("target_ball_contact").xpos.copy()
+                        self._episode_end = True
                     elif self._contact_checker(self._ball_contact_id, self._table_contact_id):  # second check contact with table
-                        self.ball_contact_after_hit = True
+                        self._ball_contact_after_hit = True
-                        self.ball_landing_pos = self.sim.data.geom("target_ball_contact").xpos.copy()
+                        self._ball_landing_pos = self.data.geom("target_ball_contact").xpos.copy()
-                        if self.ball_landing_pos[0] < 0.:  # ball lands on the opponent side
+                        if self._ball_landing_pos[0] < 0.:  # ball lands on the opponent side
-                            self.ball_return_success = True
+                            self._ball_return_success = True
+                        self._episode_end = True
+
+            # update ball trajectory & racket trajectory
+            self._ball_traj.append(self.data.body("target_ball").xpos.copy())
+            self._racket_traj.append(self.data.geom("bat").xpos.copy())
 
         self._steps += 1
-        episode_end = True if self._steps >= MAX_EPISODE_STEPS_TABLE_TENNIS else False
+        self._episode_end = True if self._steps >= MAX_EPISODE_STEPS_TABLE_TENNIS else self._episode_end
 
-        obs = self._get_obs()
+        reward = -25 if unstable_simulation else self._get_reward(self._episode_end)
 
-        return obs, 0., False, {}
+        land_dist_err = np.linalg.norm(self._ball_landing_pos[:-1] - self._goal_pos) \
+                            if self._ball_landing_pos is not None else 10.
+
+        return self._get_obs(), reward, self._episode_end, {
+            "hit_ball": self._hit_ball,
+            "ball_returned_success": self._ball_return_success,
+            "land_dist_error": land_dist_err,
+            "is_success": self._ball_return_success and land_dist_err < 0.2,
+            "num_steps": self._steps,
+        }
 
     def _contact_checker(self, id_1, id_2):
         for coni in range(0, self.data.ncon):
@@ -97,31 +127,94 @@ class TableTennisEnv(MujocoEnv, utils.EzPickle):
 
     def reset_model(self):
         self._steps = 0
-        new_context = self._sample_context()
+        self._init_ball_state = self._generate_valid_init_ball(random_pos=False, random_vel=False)
-        self.data.joint("tar_x").qpos = new_context[0]
+        self._goal_pos = self.np_random.uniform(low=self.context_bounds[0][-2:], high=self.context_bounds[1][-2:])
-        self.data.joint("tar_y").qpos = new_context[1]
+        self.data.joint("tar_x").qpos = self._init_ball_state[0]
-        self.data.joint("tar_z").qvel = 2.
+        self.data.joint("tar_y").qpos = self._init_ball_state[1]
+        self.data.joint("tar_z").qpos = self._init_ball_state[2]
+        self.data.joint("tar_x").qvel = self._init_ball_state[3]
+        self.data.joint("tar_y").qvel = self._init_ball_state[4]
+        self.data.joint("tar_z").qvel = self._init_ball_state[5]
 
-        self.ball_landing_pos = None
+        self.model.body_pos[5] = np.concatenate([self._goal_pos, [0.77]])
-        self.hit_ball = False
+
+        self.data.qpos[:7] = np.array([0., 0., 0., 1.5, 0., 0., 1.5])
+
+        mujoco.mj_forward(self.model, self.data)
+
+        self._hit_ball = False
+        self._ball_land_on_table = False
+        self._ball_contact_after_hit = False
+        self._ball_return_success = False
+        self._ball_landing_pos = None
+        self._episode_end = False
+        self._ball_traj = []
+        self._racket_traj = []
         return self._get_obs()
 
-    def _sample_context(self):
-        return self.np_random.uniform(low=self.context_bounds[0],
-                                      high=self.context_bounds[1])
 
     def _get_obs(self):
         obs = np.concatenate([
-            self.data.qpos.flat[:7],
+            self.data.qpos.flat[:7].copy(),
-            self.data.qvel.flat[:7],
+            self.data.qvel.flat[:7].copy(),
+            self.data.joint("tar_x").qpos.copy(),
+            self.data.joint("tar_y").qpos.copy(),
+            self.data.joint("tar_z").qpos.copy(),
+            # self.data.body("target_ball").xvel.copy(),
+            self._goal_pos.copy(),
         ])
         return obs
 
+    def get_obs(self):
+        return self._get_obs()
+
+    def _get_reward(self, episode_end):
+        if not episode_end:
+            return 0
+        else:
+            min_r_b_dist = np.min(np.linalg.norm(np.array(self._ball_traj) - np.array(self._racket_traj), axis=1))
+            if not self._hit_ball:
+                return 0.2 * (1 - np.tanh(min_r_b_dist**2))
+            else:
+                if self._ball_landing_pos is None:
+                    min_b_des_b_dist = np.min(np.linalg.norm(np.array(self._ball_traj)[:,:2] - self._goal_pos[:2], axis=1))
+                    return 2 * (1 - np.tanh(min_r_b_dist ** 2)) + (1 - np.tanh(min_b_des_b_dist**2))
+                else:
+                    min_b_des_b_land_dist = np.linalg.norm(self._goal_pos[:2] - self._ball_landing_pos[:2])
+                    over_net_bonus = int(self._ball_landing_pos[0] < 0)
+                    return 2 * (1 - np.tanh(min_r_b_dist ** 2)) + 4 * (1 - np.tanh(min_b_des_b_land_dist ** 2)) + over_net_bonus
+
+    def _generate_random_ball(self, random_pos=False, random_vel=False):
+        x_pos, y_pos, z_pos = -0.5, 0.35, 1.75
+        x_vel, y_vel, z_vel = 2.5, 0., 0.5
+        if random_pos:
+            x_pos = self.np_random.uniform(low=self.context_bounds[0][0], high=self.context_bounds[1][0], size=1)
+            y_pos = self.np_random.uniform(low=self.context_bounds[0][1], high=self.context_bounds[1][1], size=1)
+        if random_vel:
+            x_vel = self.np_random.uniform(low=2.0, high=3.0, size=1)
+        init_ball_state = np.array([x_pos, y_pos, z_pos, x_vel, y_vel, z_vel])
+        return init_ball_state
+
+    def _generate_valid_init_ball(self, random_pos=False, random_vel=False):
+        init_ball_state = self._generate_random_ball(random_pos=random_pos, random_vel=random_vel)
+        while not check_init_state_validity(init_ball_state):
+            init_ball_state = self._generate_random_ball(random_pos=random_pos, random_vel=random_vel)
+        return init_ball_state
+
+    def check_traj_validity(self, traj):
+        raise NotImplementedError
+
+    def get_invalid_steps(self, traj):
+        penalty = -100
+        return self._get_obs(), penalty, True, {}
 
 if __name__ == "__main__":
     env = TableTennisEnv()
-    env.reset()
     for _ in range(1000):
-        for _ in range(200):
+        obs = env.reset()
+        for _ in range(2000):
             env.render("human")
-            env.step(env.action_space.sample())
+            obs, reward, done, info = env.step(np.zeros(7))
+            print(reward)
+            if done:
+                break

fancy_gym/envs/mujoco/table_tennis/table_tennis_utils.py

@@ -1 +1,51 @@
+import numpy as np
 
+jnt_pos_low = np.array([-2.6, -2.0, -2.8, -0.9, -4.8, -1.6, -2.2])
+jnt_pos_high = np.array([2.6, 2.0, 2.8, 3.1, 1.3, 1.6, 2.2])
+delay_bound = [0.05, 0.3]
+tau_bound = [0.5, 1.5]
+
+net_height = 0.1
+table_height = 0.77
+table_x_min = -1.1
+table_x_max = 1.1
+table_y_min = -0.6
+table_y_max = 0.6
+g = 9.81
+
+def check_init_state_validity(init_state):
+    assert len(init_state) == 6, "init_state must be a 6D vector (pos+vel),got {}".format(init_state)
+    x = init_state[0]
+    y = init_state[1]
+    z = init_state[2] - table_height + 0.1
+    v_x = init_state[3]
+    v_y = init_state[4]
+    v_z = init_state[5]
+
+    # check if the initial state is wrong
+    if x > -0.2:
+        return False
+    # check if the ball velocity direction is wrong
+    if v_x < 0.:
+        return False
+    # check if the ball can pass the net
+    t_n = (-2.*(-v_z)/g + np.sqrt(4*(v_z**2)/g**2 - 8*(net_height-z)/g))/2.
+    if x + v_x * t_n < 0.05:
+        return False
+    # check if ball landing position will violate x bounds
+    t_l = (-2.*(-v_z)/g + np.sqrt(4*(v_z**2)/g**2 + 8*(z)/g))/2.
+    if x + v_x * t_l > table_x_max:
+        return False
+    # check if ball landing position will violate y bounds
+    if y + v_y * t_l > table_y_max or y + v_y * t_l < table_y_min:
+        return False
+
+    return True
+
+def magnus_force(top_spin=0.0, side_spin=0.0, v_ball=np.zeros(3), v_wind=np.zeros(3)):
+    rho = 1.225        # Air density
+    A = 1.256 * 10e-3  # Cross-section area of ball
+    C_l = 4.68 * 10e-4 - 2.0984 * 10e-5 * (np.linalg.norm(v_ball) - 50)  # Lift force coeffient or simply 1.23
+    w = np.array([0.0, top_spin, side_spin]) # Angular velocity of ball
+    f_m = 0.5 * rho * A * C_l * np.linalg.norm(v_ball-v_wind) * np.cross(w, v_ball-v_wind)
+    return f_m

fancy_gym/examples/examples_movement_primitives.py

@@ -157,17 +157,18 @@ def example_fully_custom_mp(seed=1, iterations=1, render=True):
 if __name__ == '__main__':
     render = True
     # DMP
-    example_mp("HoleReacherDMP-v0", seed=10, iterations=5, render=render)
+    # example_mp("HoleReacherDMP-v0", seed=10, iterations=5, render=render)
 
     # ProMP
-    example_mp("HoleReacherProMP-v0", seed=10, iterations=5, render=render)
+    # example_mp("HoleReacherProMP-v0", seed=10, iterations=5, render=render)
-    example_mp("BoxPushingTemporalSparseProMP-v0", seed=10, iterations=1, render=render)
+    # example_mp("BoxPushingTemporalSparseProMP-v0", seed=10, iterations=1, render=render)
+    example_mp("TableTennis4DProMP-v0", seed=10, iterations=5, render=render)
 
     # ProDMP
-    example_mp("BoxPushingDenseProDMP-v0", seed=10, iterations=16, render=render)
+    # example_mp("BoxPushingDenseProDMP-v0", seed=10, iterations=16, render=render)
 
     # Altered basis functions
-    obs1 = example_custom_mp("Reacher5dProMP-v0", seed=10, iterations=1, render=render)
+    # obs1 = example_custom_mp("Reacher5dProMP-v0", seed=10, iterations=1, render=render)
 
     # Custom MP
-    example_fully_custom_mp(seed=10, iterations=1, render=render)
+    # example_fully_custom_mp(seed=10, iterations=1, render=render)