bodyjim 1.0.1

Comma body gymnasium API

bodyjim

comma body gymnasium environment API.

Installation

To install bodyjim run the following command:

pip install bodyjim

Package requires comma body with comma three/threex running openpilot 0.9.6 or newer.

Usage

Just like other gymnasium environments, bodyjim is easy to use. Base BodyEnv accepts ip address of the body, list of cameras to stream (valid values: driver - driver camera, road - front camera, wideRoad - front wide angle camera) and list of cereal services to stream (list of services).

Environment's step method accepts action in x, y direction coordinates and retrieves next observation in form of a dict with latest camera frames and cereal messages (structure definitions) received so far. Additional info dictionary contains information about message creation timestamps and validity (which are None, if they haven't been received yet).

from bodyjim import BodyEnv

body_address = ... # body ip address, pass localhost if running locally on the body
env = BodyEnv(body_address, ["driver"], ["accelerometer", "gyroscope"], render_mode="human")
env.reset()

# action coordinates assuming the front is the screen-facing side
# x-axis: Forward (negative) / Backwards (positive)
# y-axis: Left (positive) / Right (negative)
action = (1.0, 0.0) # (x, y)
obs, reward, done, truncated, info = env.step(action)

# obs  = { "cameras": { "driver": np.ndarray }, "accelerometer": {...}, "gyroscope": {...} }
# info = { "times": <dict_of_ns_timestamps_for_each_service>, "valid": <dict_of_message_validity_for_each_service> }
driver_image = obs["camera"]["driver"] # nd.ndarray
accelerometer, accelerometer_t = obs["accelerometer"], info["times"]["accelerometer"]

By default body environment always returns reward = 0 and done = False. Subclasses can customize this behavior by overriding reward and is_done methods:

class CustomBodyEnv(BodyEnv):
  def reward(self, obs: Optional[ObsType], action: ActType, next_obs: ObsType) -> float:
    # obs - latest observations, action - most recently executed actions, next_obs - observations after executing such action
    ...

  def is_done(self, obs: Optional[ObsType], action: ActType, next_obs: ObsType) -> bool:
    # same as for reward
    ...

BodyEnv supports two rendering modes for visualization purposes:

• rgb_array - returns image formed by horizontally stacking frames from each requested camera
• human - displays pygame window with live view from cameras

Examples

Repository comes with few examples, showcasing how to use the library.

Examples require additional dependencies, which can be installed using:

pip install bodyjim[examples]

To control the body with wasd:

python3 examples/wasd.py body_ip_address [CAMERA...]

To perform "random walk":

python3 examples/random_walk.py body_ip_address [CAMERA...]

To try follow person mode, which uses YOLOv5 to detect and follow the tallest person in the frame:

python3 examples/follow_human.py body_ip_address