in gym-compete/gym_compete/new_envs/agents/ant.py [0:0]
def after_step(self, action):
xposafter = self.get_body_com("torso")[0]
forward_reward = (xposafter - self._xposbefore) / self.env.dt
if self.move_left:
forward_reward *= -1
ctrl_cost = .5 * np.square(action).sum()
cfrc_ext = self.get_cfrc_ext()
contact_cost = 0.5 * 1e-3 * np.sum(
np.square(np.clip(cfrc_ext, -1, 1))
)
qpos = self.get_qpos()
agent_standing = qpos[2] >= 0.28
survive = 1.0 if agent_standing else -1.
reward = forward_reward - ctrl_cost - contact_cost + survive
reward_info = dict()
reward_info['reward_forward'] = forward_reward
reward_info['reward_ctrl'] = ctrl_cost
reward_info['reward_contact'] = contact_cost
reward_info['reward_survive'] = survive
reward_info['reward_move'] = reward
done = not agent_standing
return reward, done, reward_info