diff --git a/.gitignore b/.gitignore
index e4ed1c0b3b..69049dad7b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,5 @@ dist
 *.egg-info
 *.so
 __pycache__
+build
+saved
diff --git a/flightlib/CMakeLists.txt b/flightlib/CMakeLists.txt
index d1162ebb5d..ce1e36179c 100644
--- a/flightlib/CMakeLists.txt
+++ b/flightlib/CMakeLists.txt
@@ -27,6 +27,7 @@ if(EIGEN_FROM_SYSTTEM)
   find_package(Eigen3 3.3.4 QUIET)
   if(EIGEN3_FOUND)
     message(STATUS "Using system provided Eigen.")
+    message(${EIGEN3_INCLUDE_DIR})
   else()
     message(STATUS "No sufficient Eigen version (3.3.4) found.")
     message(STATUS "Restoring to download Eigen sources.")
@@ -35,9 +36,10 @@ if(EIGEN_FROM_SYSTTEM)
 elseif(EIGEN_ALTERNATIVE STREQUAL "")
   include(cmake/eigen.cmake)
 else()
-  set(EIGEN_INCLUDE_DIR ${EIGEN_ALTERNATIVE})
+  set(EIGEN_INCLUDE_DIR ${cl})
 endif()
 
+
 # Including dependencies 
 include(cmake/pybind11.cmake)
 include(cmake/yaml.cmake)
@@ -198,7 +200,10 @@ if(NOT FLIGHTLIB_SOURCES)
 	set(LIBRARY_NAME)
 else()
   # flightlib
-	add_library(${PROJECT_NAME} ${FLIGHTLIB_SOURCES})
+  add_library(${PROJECT_NAME} ${FLIGHTLIB_SOURCES})
+  # target_include_directories(${PROJECT_NAME} PRIVATE
+  #   ${PROJECT_SOURCE_DIR}/externals/pybind11-src/include
+  # )
   target_link_libraries(${PROJECT_NAME} PRIVATE
     ${OpenCV_LIBRARIES}
     yaml-cpp
@@ -214,8 +219,9 @@ if(FLIGHTLIB_GYM_SOURCES)
     ${FLIGHTLIB_GYM_SOURCES})
   target_include_directories(flightgym PRIVATE
     ${PROJECT_SOURCE_DIR}/externals/pybind11-src/include
-    ${PROJECT_SOURCE_DIR}/include)
-  target_link_libraries(flightgym PRIVATE ${LIBRARY_NAME})
+    ${PROJECT_SOURCE_DIR}/include
+    ${EIGEN3_INCLUDE_DIR})
+  target_link_libraries(flightgym PRIVATE ${LIBRARY_NAME} )
 endif()
 
 if(ENABLE_BLAS AND BLAS_FOUND AND LAPACK_FOUND)
diff --git a/flightlib/cmake/pybind11.cmake b/flightlib/cmake/pybind11.cmake
index fc45a73040..7b3461f459 100644
--- a/flightlib/cmake/pybind11.cmake
+++ b/flightlib/cmake/pybind11.cmake
@@ -1,6 +1,9 @@
 # Download and unpack pybind11 at configure time
 message(STATUS "Getting Pybind11...")
 
+# set(PYBIND11_PYTHON_VERSION 3.6)
+set(PYBIND11_PYTHON_VERSION ${PYTHON_VERSION_STRING})   
+
 configure_file(
   cmake/pybind11_download.cmake
   ${PROJECT_SOURCE_DIR}/externals/pybind11/CMakeLists.txt)
diff --git a/flightlib/cmake/pybind11_download.cmake b/flightlib/cmake/pybind11_download.cmake
index a293f36db8..43672ae5da 100644
--- a/flightlib/cmake/pybind11_download.cmake
+++ b/flightlib/cmake/pybind11_download.cmake
@@ -5,7 +5,7 @@ project(pybind11-download)
 include(ExternalProject)
 ExternalProject_Add(pybind11
   GIT_REPOSITORY    https://github.com/pybind/pybind11.git
-  GIT_TAG           master
+  GIT_TAG           v2.4.3
   SOURCE_DIR        "${PROJECT_SOURCE_DIR}/externals/pybind11-src"
   BINARY_DIR        "${PROJECT_SOURCE_DIR}/externals/pybind11-bin"
   CONFIGURE_COMMAND ""
diff --git a/flightlib/configs/quadrotor_env.yaml b/flightlib/configs/quadrotor_env.yaml
index 754161630c..66ba3fdfdc 100644
--- a/flightlib/configs/quadrotor_env.yaml
+++ b/flightlib/configs/quadrotor_env.yaml
@@ -1,3 +1,5 @@
+hello: 12
+render: no
 env:
   seed: 1
   scene_id: 0  # 0 warehouse, 1 garage, 3 natureforest
@@ -10,7 +12,7 @@ env:
 quadrotor:
   mass: 0.73
   arm_length: 0.17
-  rotor_drag_coeff: 0.016 
+  rotor_drag_coeff: 0.016
   inertia: [0.007, 0.007, 0.012]
   camera: no
 
diff --git a/flightlib/include/flightlib/bridges/unity_bridge.hpp b/flightlib/include/flightlib/bridges/unity_bridge.hpp
index 18e14c5737..01014fb45a 100644
--- a/flightlib/include/flightlib/bridges/unity_bridge.hpp
+++ b/flightlib/include/flightlib/bridges/unity_bridge.hpp
@@ -8,7 +8,7 @@
 #include <string>
 #include <unordered_map>
 
-// Include ZMQ bindings for comms with Unity.
+// Include ZMQ bindings for communications with Unity.
 #include <zmqpp/zmqpp.hpp>
 
 // flightlib
diff --git a/flightlib/include/flightlib/common/types.hpp b/flightlib/include/flightlib/common/types.hpp
index 56f6f3152c..ea72996b05 100644
--- a/flightlib/include/flightlib/common/types.hpp
+++ b/flightlib/include/flightlib/common/types.hpp
@@ -7,7 +7,7 @@ namespace flightlib {
 // ------------ General Stuff-------------
 
 // Define the scalar type used.
-using Scalar = double;
+using Scalar = float;
 
 // Define frame id for unity
 using FrameID = uint64_t;
@@ -27,7 +27,7 @@ template<int rows = Dynamic, int cols = rows>
 using Matrix = Eigen::Matrix<Scalar, rows, cols>;
 
 // Using shorthand for `Matrix<ros, cols>` with scalar type.
-template<int rows = Dynamic, int cols = rows>
+template<int rows = Dynamic, int cols = Dynamic>
 using MatrixRowMajor = Eigen::Matrix<Scalar, rows, cols, Eigen::RowMajor>;
 
 // Using shorthand for `Vector<ros>` with scalar type.
diff --git a/flightlib/include/flightlib/envs/env_base.hpp b/flightlib/include/flightlib/envs/env_base.hpp
index fae3954b6e..d4a9c843e2 100644
--- a/flightlib/include/flightlib/envs/env_base.hpp
+++ b/flightlib/include/flightlib/envs/env_base.hpp
@@ -22,7 +22,7 @@ class EnvBase {
   virtual ~EnvBase() = 0;
 
   // (pure virtual) public methods (has to be implemented by child classes)
-  virtual bool reset(Ref<Vector<>> obs) = 0;
+  virtual void reset(Ref<Vector<>> obs) = 0;
   virtual Scalar step(Ref<Vector<>> act, Ref<Vector<>> obs) = 0;
   virtual bool getObs(Ref<Vector<>> obs) = 0;
   virtual bool setFlightmare(bool on) = 0;
diff --git a/flightlib/include/flightlib/envs/quadrotor_env/quadrotor_env.hpp b/flightlib/include/flightlib/envs/quadrotor_env/quadrotor_env.hpp
index 62ec73840e..3efa6e0406 100644
--- a/flightlib/include/flightlib/envs/quadrotor_env/quadrotor_env.hpp
+++ b/flightlib/include/flightlib/envs/quadrotor_env/quadrotor_env.hpp
@@ -22,7 +22,7 @@ class QuadrotorEnv final : public EnvBase {
   ~QuadrotorEnv();
 
   // - public OpenAI-gym-style functions
-  bool reset(Ref<Vector<>> obs) override;
+  void reset(Ref<Vector<>> obs) override;
   Scalar step(Ref<Vector<>> act, Ref<Vector<>> obs) override;
 
   // - public set functions
diff --git a/flightlib/include/flightlib/envs/test_env.hpp b/flightlib/include/flightlib/envs/test_env.hpp
index 2ea6749224..7a3cace054 100644
--- a/flightlib/include/flightlib/envs/test_env.hpp
+++ b/flightlib/include/flightlib/envs/test_env.hpp
@@ -1,5 +1,11 @@
 #pragma once
 
+// pybind11
+// #include <pybind11/eigen.h>
+// #include <pybind11/pybind11.h>
+// #include <pybind11/stl.h>
+#include <eigen3/Eigen/Eigen>
+
 #include "flightlib/envs/env_base.hpp"
 #include "flightlib/envs/quadrotor_env/quadrotor_env.hpp"
 
@@ -9,8 +15,13 @@ template<typename EnvBase>
 class TestEnv {
  public:
   // constructor & deconstructor
-  explicit TestEnv();
+  TestEnv();
   ~TestEnv();
+
+  void reset(
+    Eigen::Ref<
+      Eigen::Matrix<float, Eigen::Dynamic, Eigen::Dynamic, Eigen::RowMajor>>
+      obs);
 };
 
 }  // namespace flightlib
diff --git a/flightlib/include/flightlib/envs/vec_env.hpp b/flightlib/include/flightlib/envs/vec_env.hpp
index fef3265089..0fb570c09a 100644
--- a/flightlib/include/flightlib/envs/vec_env.hpp
+++ b/flightlib/include/flightlib/envs/vec_env.hpp
@@ -17,7 +17,8 @@ namespace flightlib {
 template<typename EnvBase>
 class VecEnv {
  public:
-  explicit VecEnv(std::string cfg_path);
+  VecEnv();
+  VecEnv(const std::string& cfg_path);
   ~VecEnv();
 
   // - public OpenAI-gym style functions for vectorized environment
@@ -36,6 +37,9 @@ class VecEnv {
   inline int getActDim(void) { return act_dim_; };
   inline int getExtraInfoDim(void) { return extra_info_names_.size(); };
   inline int getNumOfEnvs(void) { return envs_.size(); };
+  inline std::vector<std::string>& getExtraInfoNames() {
+    return extra_info_names_;
+  };
 
   // - auxiliary functions
   void isTerminalState(Ref<BoolVector<>> terminal_state);
@@ -55,6 +59,7 @@ class VecEnv {
   //
   std::vector<std::unique_ptr<EnvBase>> envs_;
   std::vector<std::string> extra_info_names_;
+
   std::unique_ptr<Logger> logger_;
 
   // auxiliar variables
diff --git a/flightlib/src/envs/quadrotor_env/quadrotor_env.cpp b/flightlib/src/envs/quadrotor_env/quadrotor_env.cpp
index a8113bc4a9..e15ef7e843 100644
--- a/flightlib/src/envs/quadrotor_env/quadrotor_env.cpp
+++ b/flightlib/src/envs/quadrotor_env/quadrotor_env.cpp
@@ -6,12 +6,11 @@ QuadrotorEnv::QuadrotorEnv() : EnvBase() {
   // define input and output dimension for the environment
   obs_dim_ = CtlObsAct::kObsSize;
   act_dim_ = CtlObsAct::kActSize;
-  std::cout << "Quadrotor Env." << std::endl;
 }
 
 QuadrotorEnv::~QuadrotorEnv() {}
 
-bool QuadrotorEnv::reset(const Ref<Vector<>> obs) {
+void QuadrotorEnv::reset(const Ref<Vector<>> obs) {
   quad_state_.setZero();
 
   // randomly reset the quadrotor state
@@ -31,7 +30,6 @@ bool QuadrotorEnv::reset(const Ref<Vector<>> obs) {
 
   // obtain observations
   getObs(obs);
-  return true;
 }
 
 bool QuadrotorEnv::getObs(Ref<Vector<>> obs) {
diff --git a/flightlib/src/envs/test_env.cpp b/flightlib/src/envs/test_env.cpp
index 316f62b2e6..d69d264923 100644
--- a/flightlib/src/envs/test_env.cpp
+++ b/flightlib/src/envs/test_env.cpp
@@ -11,6 +11,14 @@ TestEnv<EnvBase>::TestEnv() {
 template<typename EnvBase>
 TestEnv<EnvBase>::~TestEnv() {}
 
+template<typename EnvBase>
+void TestEnv<EnvBase>::reset(
+  Eigen::Ref<
+    Eigen::Matrix<float, Eigen::Dynamic, Eigen::Dynamic, Eigen::RowMajor>>
+    obs) {
+  obs << 1, 2, 3, 4, 5, 6, 7, 8, 9;
+}
+
 template class TestEnv<QuadrotorEnv>;
 
 }  // namespace flightlib
diff --git a/flightlib/src/envs/vec_env.cpp b/flightlib/src/envs/vec_env.cpp
index abb596f795..170a02e7b3 100644
--- a/flightlib/src/envs/vec_env.cpp
+++ b/flightlib/src/envs/vec_env.cpp
@@ -3,20 +3,24 @@
 namespace flightlib {
 
 template<typename EnvBase>
-VecEnv<EnvBase>::VecEnv(const std::string cfg_path) {
+VecEnv<EnvBase>::VecEnv()
+  : VecEnv(getenv("FLIGHTMARE_PATH") +
+           std::string("/flightlib/configs/quadrotor_env.yaml")) {}
+
+template<typename EnvBase>
+VecEnv<EnvBase>::VecEnv(const std::string& cfg_path) {
   // load environment configuration
-  cfg_ = YAML::Load(cfg_path);
+  cfg_ = YAML::LoadFile(cfg_path);
 
   // logger
   logger_ = std::make_unique<Logger>("VecEnv");
 
-  //
-  if (cfg_["env"]["render"])
-    unity_render_ = cfg_["env"]["render"].template as<bool>();
-  logger_->info("environment created.");
+  if (cfg_["env"]["render"]) {
+    unity_render_ = cfg_["env"]["render"].as<bool>();
+  }
 
-  omp_set_num_threads(cfg_["env"]["num_threads"].template as<int>());
-  num_envs_ = cfg_["env"]["num_envs"].template as<int>();
+  omp_set_num_threads(cfg_["env"]["num_threads"].as<int>());
+  num_envs_ = cfg_["env"]["num_envs"].as<int>();
 
   // create & setup environments
   const bool render = false;
@@ -29,6 +33,7 @@ VecEnv<EnvBase>::VecEnv(const std::string cfg_path) {
   if (unity_render_) {
     // enable rendering for only one environment
     envs_[0]->setFlightmare(unity_render_);
+    logger_->info("Flightmare Unity Render is enabled!");
   }
 
   obs_dim_ = envs_[0]->getObsDim();
@@ -40,8 +45,6 @@ VecEnv<EnvBase>::VecEnv(const std::string cfg_path) {
   for (auto& re : envs_[0]->extra_info_) {
     extra_info_names_.push_back(re.first);
   }
-
-  std::cout << "Vec Env" << std::endl;
 }
 
 template<typename EnvBase>
@@ -123,6 +126,9 @@ void VecEnv<EnvBase>::connectFlightmare(void) {}
 template<typename EnvBase>
 void VecEnv<EnvBase>::disconnectFlightmare(void) {}
 
+template<typename EnvBase>
+void VecEnv<EnvBase>::curriculumUpdate(void) {}
+
 // IMPORTANT. Otherwise:
 // Segmentation fault (core dumped)
 template class VecEnv<QuadrotorEnv>;
diff --git a/flightlib/src/wrapper/pybind_wrapper.cpp b/flightlib/src/wrapper/pybind_wrapper.cpp
index 85de68903c..ee9f26c3f0 100644
--- a/flightlib/src/wrapper/pybind_wrapper.cpp
+++ b/flightlib/src/wrapper/pybind_wrapper.cpp
@@ -1,5 +1,6 @@
 
 // pybind11
+#include <pybind11/eigen.h>
 #include <pybind11/pybind11.h>
 #include <pybind11/stl.h>
 
@@ -14,18 +15,21 @@ using namespace flightlib;
 
 PYBIND11_MODULE(flightgym, m) {
   py::class_<VecEnv<QuadrotorEnv>>(m, "QuadrotorEnv_v1")
-    .def(py::init<std::string>())
+    .def(py::init<>())
+    .def(py::init<const std::string&>())
     .def("reset", &VecEnv<QuadrotorEnv>::reset)
     .def("step", &VecEnv<QuadrotorEnv>::step)
     .def("testStep", &VecEnv<QuadrotorEnv>::testStep)
     .def("setSeed", &VecEnv<QuadrotorEnv>::setSeed)
     .def("close", &VecEnv<QuadrotorEnv>::close)
     .def("isTerminalState", &VecEnv<QuadrotorEnv>::isTerminalState)
+    .def("curriculumUpdate", &VecEnv<QuadrotorEnv>::curriculumUpdate)
     .def("connectFlightmare", &VecEnv<QuadrotorEnv>::connectFlightmare)
     .def("disconnectFlightmare", &VecEnv<QuadrotorEnv>::disconnectFlightmare)
     .def("getNumOfEnvs", &VecEnv<QuadrotorEnv>::getNumOfEnvs)
     .def("getObsDim", &VecEnv<QuadrotorEnv>::getObsDim)
     .def("getActDim", &VecEnv<QuadrotorEnv>::getActDim)
+    .def("getExtraInfoNames", &VecEnv<QuadrotorEnv>::getExtraInfoNames)
     .def("__repr__", [](const VecEnv<QuadrotorEnv>& a) {
       return "RPG Drone Racing Environment";
     });
@@ -46,5 +50,6 @@ PYBIND11_MODULE(flightgym, m) {
 
   py::class_<TestEnv<QuadrotorEnv>>(m, "TestEnv_v0")
     .def(py::init<>())
+    .def("reset", &TestEnv<QuadrotorEnv>::reset)
     .def("__repr__", [](const TestEnv<QuadrotorEnv>& a) { return "Test Env"; });
 }
\ No newline at end of file
diff --git a/flightlib/test.py b/flightlib/test.py
index 5a6166c66c..ca6fea2032 100644
--- a/flightlib/test.py
+++ b/flightlib/test.py
@@ -1,11 +1,20 @@
+import numpy as np
+
 from flightgym import TestEnv_v0
 from flightgym import QuadrotorEnv_v0
 from flightgym import QuadrotorEnv_v1
 
 def main():
   test_env = TestEnv_v0()
-  quad_env0 = QuadrotorEnv_v0()
+  # quad_env0 = QuadrotorEnv_v0()
+  obs = np.zeros(shape=(3, 3), dtype=np.float32)
+  test_env.reset(obs)
+  print(obs)
+
   quad_env1 = QuadrotorEnv_v1()
+  obs = np.zeros(shape=(1, 9), dtype=np.float32)
+  quad_env1.reset(obs)
+  print(obs)
 
 if __name__ == "__main__":
     main()
diff --git a/flightlib/tests/envs/quadrotor_env.cpp b/flightlib/tests/envs/quadrotor_env.cpp
index 19b8492772..6a790bc2d3 100644
--- a/flightlib/tests/envs/quadrotor_env.cpp
+++ b/flightlib/tests/envs/quadrotor_env.cpp
@@ -15,16 +15,9 @@ TEST(QuadrotorEnv, Constructor) {
   Logger logger("QuadrotorEnv");
   logger.info("Environment configuration path \"%s\".", config_path.c_str());
 
-  std::string env_path = getenv("HOME");
-  logger.info("Environment configuration path \"%s\".", env_path.c_str());
-
-  std::ofstream file;
-  file.open(config_path);
-  std::cout << file.is_open() << std::endl;
-
   //
   YAML::Node cfg = YAML::LoadFile(config_path);
-  QuadrotorEnv env();
+  QuadrotorEnv env;
 
   //
   QuadState quad_state;
diff --git a/flightlib/tests/envs/vec_env.cpp b/flightlib/tests/envs/vec_env.cpp
new file mode 100644
index 0000000000..4c2db6babe
--- /dev/null
+++ b/flightlib/tests/envs/vec_env.cpp
@@ -0,0 +1,25 @@
+#include "flightlib/envs/vec_env.hpp"
+#include "flightlib/envs/quadrotor_env/quadrotor_env.hpp"
+
+#include <gtest/gtest.h>
+#include <yaml-cpp/yaml.h>
+#include <fstream>
+#include <iostream>
+
+using namespace flightlib;
+
+TEST(VecEnv, Constructor) {
+  std::string config_path =
+    getenv("FLIGHTMARE_PATH") +
+    std::string("/flightlib/configs/quadrotor_env.yaml");
+
+  Logger logger("VecEnv TEST");
+  logger.info("Environment configuration path \"%s\".", config_path.c_str());
+
+  VecEnv<QuadrotorEnv> env(config_path);
+
+  env.setSeed(10);
+
+  int obs_dim = env.getObsDim();
+  std::cout << "obs_dim : " << obs_dim << std::endl;
+}
\ No newline at end of file
diff --git a/flightrl/build/lib/rpg_baselines/__init__.py b/flightrl/build/lib/rpg_baselines/__init__.py
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/flightrl/rpg_baselines/common/policies.py b/flightrl/rpg_baselines/common/policies.py
index 484ef20443..d24b18b693 100644
--- a/flightrl/rpg_baselines/common/policies.py
+++ b/flightrl/rpg_baselines/common/policies.py
@@ -12,7 +12,7 @@
 #     MultiCategoricalProbabilityDistribution, DiagGaussianProbabilityDistribution, BernoulliProbabilityDistribution
 from stable_baselines.common.input import observation_input
 #
-from alpha_baselines.common.distributions import make_proba_dist_type, CategoricalProbabilityDistribution, \
+from rpg_baselines.common.distributions import make_proba_dist_type, CategoricalProbabilityDistribution, \
     MultiCategoricalProbabilityDistribution, DiagGaussianProbabilityDistribution, BernoulliProbabilityDistribution
 
 
diff --git a/flightrl/rpg_baselines/envs/vec_env_wrapper.py b/flightrl/rpg_baselines/envs/vec_env_wrapper.py
index a729803d3a..3d46173e8c 100644
--- a/flightrl/rpg_baselines/envs/vec_env_wrapper.py
+++ b/flightrl/rpg_baselines/envs/vec_env_wrapper.py
@@ -2,13 +2,13 @@
 from gym import spaces
 from stable_baselines.common.vec_env import VecEnv
 
-class AlphaGymVec(VecEnv):
+class FlightEnvVec(VecEnv):
     #
     def __init__(self, impl):
         self.wrapper = impl
-        self.wrapper.init()
         self.num_obs = self.wrapper.getObsDim()
         self.num_acts = self.wrapper.getActDim()
+        print(self.num_obs, self.num_acts)
         self._observation_space = spaces.Box(
           np.ones(self.num_obs) * -np.Inf, 
           np.ones(self.num_obs) * np.Inf, dtype=np.float32)
diff --git a/flightrl/run_drone_control.py b/flightrl/run_drone_control.py
index e69de29bb2..57630ce790 100644
--- a/flightrl/run_drone_control.py
+++ b/flightrl/run_drone_control.py
@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+
+import os
+import math
+import argparse
+import tensorflow as tf
+import numpy as np
+
+#
+from stable_baselines import logger
+
+#
+from rpg_baselines.common.policies import MlpPolicy
+from rpg_baselines.common.util import ConfigurationSaver, TensorboardLauncher
+from rpg_baselines.ppo.ppo2 import PPO2
+from rpg_baselines.envs import vec_env_wrapper as wrapper
+#
+from flightgym import QuadrotorEnv_v1
+
+#
+def parser():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('--quad_env_cfg', type=str, default=os.path.abspath("../../configs/env.yaml"),
+    help='configuration file of the quad environment')
+  parser.add_argument('--train', type=int, default=1,
+    help="To train new model or simply test pre-trained model")
+  parser.add_argument('--save_dir', type=str, default=os.path.dirname(os.path.realpath(__file__)),
+    help="Directory where to save the checkpoints and training metrics")
+  parser.add_argument('--env', type=str, default="QuadrotorEnv_v1",
+    help="environment name")
+  parser.add_argument('--seed', type=int, default=0,
+    help="Random seed")
+  parser.add_argument('--load_dir', type=str,
+    help="Directory where to load weights")
+  parser.add_argument('-m', '--mode', type=str, default='train',
+    help='set mode either train or test')
+  parser.add_argument('-w', '--weight', type=str, default='./saved/2020-07-23-15-41-33.zip',
+    help='trained weight path')
+  return parser
+
+def main():
+  args = parser().parse_args()
+  mode = args.mode
+
+  env = wrapper.FlightEnvVec(QuadrotorEnv_v1())
+
+  # set random seed
+  env.seed(args.seed)
+  np.random.seed(args.seed)
+  tf.set_random_seed(args.seed)
+
+  #
+  if mode == 'train':
+    # save the configuration and other files
+    rsg_root = os.path.dirname(os.path.abspath(__file__))
+    log_dir = rsg_root + '/saved'
+    saver = ConfigurationSaver(log_dir=log_dir)
+    model = PPO2(
+      tensorboard_log=saver.data_dir,
+      policy=MlpPolicy, #  check activation function
+      policy_kwargs=dict(net_arch=[dict(pi=[128, 128], vf=[128, 128])], act_fun=tf.nn.relu),
+      env=env,
+      lam=0.95,
+      gamma=0.99,  # lower 0.9 ~ 0.99
+      # n_steps=math.floor(cfg['env']['max_time'] / cfg['env']['ctl_dt']),
+      n_steps=250,
+      ent_coef=0.00,
+      learning_rate=3e-4,
+      vf_coef=0.5,
+      max_grad_norm=0.5,
+      nminibatches=1,
+      noptepochs=10,
+      cliprange=0.2,
+      verbose=1,
+    )
+
+    # tensorboard
+    # Make sure that your chrome browser is already on.
+    # TensorboardLauncher(saver.data_dir + '/PPO2_1')
+
+    # PPO run
+    # Originally the total timestep is 5 x 10^8
+    # 10 zeros for nupdates to be 4000
+    # 1000000000 is 2000 iterations and so
+    # 2000000000 is 4000 iterations.
+    logger.configure(folder=saver.data_dir)
+    model.learn(
+      total_timesteps=int(25000000),
+      log_dir=saver.data_dir, logger=logger)
+    model.save(saver.data_dir)
+
+  # # Testing mode with a trained weight
+  # else:
+  #   model = PPO2.load(args.weight)
+  #   test_ppo2(env, model, render=True)
+
+if __name__ == "__main__":
+  main()