Getting Started
This tutorial demonstrates the configuration and use of a simple BSK-RL environment. BSK-RL and dependencies should already be installed at this point (see Installation if you haven’t installed the package yet).
Load Modules
In this tutorial, the environment will be created with gym.make, so it is necessary to import the top-level bsk_rl module as well as gym and bsk_rl components.
[1]:
from typing import ClassVar
import gymnasium as gym
import numpy as np
from Basilisk.architecture import bskLogging
from bsk_rl import act, data, obs, sats, scene
from bsk_rl.sim import dyn, fsw
bskLogging.setDefaultLogLevel(bskLogging.BSK_WARNING)
If no errors were raised, you have a functional installation of bsk_rl.
Configure the Satellite
Satellites are configurable agents in the environment. To make a new environment, start by specifying the observations and actions of a satellite type, as well as the underlying Basilisk simulation models used by the satellite.
[2]:
class MyScanningSatellite(sats.AccessSatellite):
observation_spec: ClassVar[list[obs.Observation]] = [
obs.SatProperties(
dict(prop="storage_level_fraction"),
dict(prop="battery_charge_fraction")
),
obs.Eclipse(),
]
action_spec: ClassVar[list[act.Action]] = [
act.Scan(duration=60.0), # Scan for 1 minute
act.Charge(duration=600.0), # Charge for 10 minutes
]
dyn_type = dyn.ContinuousImagingDynModel
fsw_type = fsw.ContinuousImagingFSWModel
Based on this class specification, a list of configurable parameters for the satellite can be generated.
[3]:
MyScanningSatellite.default_sat_args()
[3]:
{'hs_min': 0.0,
'maxCounterValue': 4,
'thrMinFireTime': 0.02,
'desatAttitude': 'sun',
'controlAxes_B': [1, 0, 0, 0, 1, 0, 0, 0, 1],
'thrForceSign': 1,
'K': 7.0,
'Ki': -1,
'P': 35.0,
'imageAttErrorRequirement': 0.01,
'imageRateErrorRequirement': None,
'inst_pHat_B': [0, 0, 1],
'utc_init': 'this value will be set by the world model',
'batteryStorageCapacity': 288000.0,
'storedCharge_Init': <function bsk_rl.sim.dyn.base.BasicDynamicsModel.<lambda>()>,
'disturbance_vector': None,
'dragCoeff': 2.2,
'panelArea': 1.0,
'imageTargetMaximumRange': -1,
'instrumentBaudRate': 8000000.0,
'instrumentPowerDraw': -30.0,
'basePowerDraw': 0.0,
'wheelSpeeds': <function bsk_rl.sim.dyn.base.BasicDynamicsModel.<lambda>()>,
'maxWheelSpeed': inf,
'u_max': 0.2,
'rwBasePower': 0.4,
'rwMechToElecEfficiency': 0.0,
'rwElecToMechEfficiency': 0.5,
'panelEfficiency': 0.2,
'nHat_B': array([ 0, 0, -1]),
'mass': 330,
'width': 1.38,
'depth': 1.04,
'height': 1.58,
'sigma_init': <function bsk_rl.sim.dyn.base.DynamicsModel.<lambda>()>,
'omega_init': <function bsk_rl.sim.dyn.base.DynamicsModel.<lambda>()>,
'rN': None,
'vN': None,
'oe': <function bsk_rl.utils.orbital.random_orbit(i: Optional[float] = None, a: Optional[float] = 6871, e: float = 0, Omega: Optional[float] = None, omega: Optional[float] = None, f: Optional[float] = None, alt: float = None, r_body: float = 6371) -> Basilisk.utilities.orbitalMotion.ClassicElements>,
'mu': 398600436000000.0,
'min_orbital_radius': 6578136.6,
'dataStorageCapacity': 160000000.0,
'storageUnitValidCheck': False,
'storageInit': 0,
'thrusterPowerDraw': 0.0,
'transmitterBaudRate': -8000000.0,
'transmitterNumBuffers': 100,
'transmitterPacketSize': None,
'transmitterPowerDraw': -15.0}
When instantiating a satellite, these parameters can be overriden with a constant or rerandomized every time the environment is reset using the sat_args dictionary.
[4]:
sat_args = {}
# Set some parameters as constants
sat_args["imageAttErrorRequirement"] = 0.05
sat_args["dataStorageCapacity"] = 1e10
sat_args["instrumentBaudRate"] = 1e7
sat_args["storedCharge_Init"] = 50000.0
# Randomize the initial storage level on every reset
sat_args["storageInit"] = lambda: np.random.uniform(0.25, 0.75) * 1e10
# Make the satellite
sat = MyScanningSatellite(name="EO1", sat_args=sat_args)
Making the Environment
For this example, we will be using the single-agent SatelliteTasking environment. Along with passing the satellite that we configured, the environment takes a scenario, which defines the environment the satellite is acting in, and a rewarder, which defines how data collected from the scenario is rewarded.
[5]:
env = gym.make(
"SatelliteTasking-v1",
satellite=sat,
scenario=scene.UniformNadirScanning(),
rewarder=data.ScanningTimeReward(),
time_limit=5700.0, # approximately 1 orbit
log_level="INFO",
)
2026-09-02 14:53:23,453 gym INFO Calling env.reset() to get observation space
2026-09-02 14:53:23,454 gym INFO Resetting environment with seed=4096100203
2026-09-02 14:53:23,496 sats.satellite.EO1 INFO <0.00> EO1: Finding opportunity windows from 0.00 to 6000.00 seconds
2026-09-02 14:53:23,507 gym INFO <0.00> Environment reset
Interacting with the Environment
First, the environment is reset.
[6]:
observation, info = env.reset(seed=1)
2026-09-02 14:53:23,513 gym INFO Resetting environment with seed=1
2026-09-02 14:53:23,531 sats.satellite.EO1 INFO <0.00> EO1: Finding opportunity windows from 0.00 to 6000.00 seconds
2026-09-02 14:53:23,540 gym INFO <0.00> Environment reset
Next, we take the scan action (action=0) a few times. This allows for the satellite to settle its attitude in the nadir pointing mode to satisfy imaging conditions. Note that the logs show little or no data accumulated in the first two steps as it settles, but achieves 60 reward (corresponding to 60 seconds of imaging) by the third step.
[7]:
print("Initial data level:", observation[0], "(randomized by sat_args)")
for _ in range(3):
observation, reward, terminated, truncated, info = env.step(action=0)
print(" Final data level:", observation[0])
2026-09-02 14:53:23,545 gym INFO <0.00> === STARTING STEP ===
2026-09-02 14:53:23,546 sats.satellite.EO1 INFO <0.00> EO1: action_nadir_scan tasked for 60.0 seconds
2026-09-02 14:53:23,547 sats.satellite.EO1 INFO <0.00> EO1: setting timed terminal event at 60.0
2026-09-02 14:53:23,551 sats.satellite.EO1 INFO <60.00> EO1: timed termination at 60.0 for action_nadir_scan
2026-09-02 14:53:23,552 data.base INFO <60.00> Total reward: {}
2026-09-02 14:53:23,553 comm.communication INFO <60.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,553 sats.satellite.EO1 INFO <60.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,555 gym INFO <60.00> Step reward: 0.0
2026-09-02 14:53:23,555 gym INFO <60.00> === STARTING STEP ===
2026-09-02 14:53:23,556 sats.satellite.EO1 INFO <60.00> EO1: action_nadir_scan tasked for 60.0 seconds
2026-09-02 14:53:23,556 sats.satellite.EO1 INFO <60.00> EO1: setting timed terminal event at 120.0
2026-09-02 14:53:23,560 sats.satellite.EO1 INFO <120.00> EO1: timed termination at 120.0 for action_nadir_scan
2026-09-02 14:53:23,561 data.base INFO <120.00> Total reward: {'EO1': 24.0}
2026-09-02 14:53:23,562 comm.communication INFO <120.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,562 sats.satellite.EO1 INFO <120.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,564 gym INFO <120.00> Step reward: 24.0
2026-09-02 14:53:23,564 gym INFO <120.00> === STARTING STEP ===
2026-09-02 14:53:23,564 sats.satellite.EO1 INFO <120.00> EO1: action_nadir_scan tasked for 60.0 seconds
2026-09-02 14:53:23,565 sats.satellite.EO1 INFO <120.00> EO1: setting timed terminal event at 180.0
2026-09-02 14:53:23,569 sats.satellite.EO1 INFO <180.00> EO1: timed termination at 180.0 for action_nadir_scan
2026-09-02 14:53:23,570 data.base INFO <180.00> Total reward: {'EO1': 60.0}
2026-09-02 14:53:23,570 comm.communication INFO <180.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,571 sats.satellite.EO1 INFO <180.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,572 gym INFO <180.00> Step reward: 60.0
Initial data level: 0.5961613078 (randomized by sat_args)
Final data level: 0.6801613078
The observation reflects the increase in stored data. The first element, corresponding to storage_level_fraction, starts at a random value set by the storageInit function in sat_args and increases based on the time spent imaging.
Finally, the charging mode is tasked repeatedly in 10-minute increments until the environment time limit is reached.
[8]:
while not truncated:
observation, reward, terminated, truncated, info = env.step(action=1)
print(f"Charge level: {observation[1]:.3f} ({env.unwrapped.simulator.sim_time:.1f} seconds)\n\tEclipse: start: {observation[2]:.1f} end: {observation[3]:.1f}")
2026-09-02 14:53:23,578 gym INFO <180.00> === STARTING STEP ===
2026-09-02 14:53:23,578 sats.satellite.EO1 INFO <180.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,578 sats.satellite.EO1 INFO <180.00> EO1: setting timed terminal event at 780.0
2026-09-02 14:53:23,609 sats.satellite.EO1 INFO <780.00> EO1: timed termination at 780.0 for action_charge
2026-09-02 14:53:23,609 data.base INFO <780.00> Total reward: {}
2026-09-02 14:53:23,610 comm.communication INFO <780.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,610 sats.satellite.EO1 INFO <780.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,613 gym INFO <780.00> Step reward: 0.0
2026-09-02 14:53:23,614 gym INFO <780.00> === STARTING STEP ===
2026-09-02 14:53:23,614 sats.satellite.EO1 INFO <780.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,614 sats.satellite.EO1 INFO <780.00> EO1: setting timed terminal event at 1380.0
2026-09-02 14:53:23,644 sats.satellite.EO1 INFO <1380.00> EO1: timed termination at 1380.0 for action_charge
2026-09-02 14:53:23,645 data.base INFO <1380.00> Total reward: {}
2026-09-02 14:53:23,645 comm.communication INFO <1380.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,646 sats.satellite.EO1 INFO <1380.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,647 gym INFO <1380.00> Step reward: 0.0
2026-09-02 14:53:23,647 gym INFO <1380.00> === STARTING STEP ===
2026-09-02 14:53:23,648 sats.satellite.EO1 INFO <1380.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,648 sats.satellite.EO1 INFO <1380.00> EO1: setting timed terminal event at 1980.0
2026-09-02 14:53:23,678 sats.satellite.EO1 INFO <1980.00> EO1: timed termination at 1980.0 for action_charge
2026-09-02 14:53:23,679 data.base INFO <1980.00> Total reward: {}
2026-09-02 14:53:23,679 comm.communication INFO <1980.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,680 sats.satellite.EO1 INFO <1980.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,681 gym INFO <1980.00> Step reward: 0.0
2026-09-02 14:53:23,682 gym INFO <1980.00> === STARTING STEP ===
2026-09-02 14:53:23,682 sats.satellite.EO1 INFO <1980.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,683 sats.satellite.EO1 INFO <1980.00> EO1: setting timed terminal event at 2580.0
2026-09-02 14:53:23,713 sats.satellite.EO1 INFO <2580.00> EO1: timed termination at 2580.0 for action_charge
2026-09-02 14:53:23,714 data.base INFO <2580.00> Total reward: {}
2026-09-02 14:53:23,714 comm.communication INFO <2580.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,715 sats.satellite.EO1 INFO <2580.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,716 gym INFO <2580.00> Step reward: 0.0
2026-09-02 14:53:23,717 gym INFO <2580.00> === STARTING STEP ===
2026-09-02 14:53:23,717 sats.satellite.EO1 INFO <2580.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,717 sats.satellite.EO1 INFO <2580.00> EO1: setting timed terminal event at 3180.0
Charge level: 0.633 (780.0 seconds)
Eclipse: start: 5610.0 end: 2040.0
Charge level: 0.630 (1380.0 seconds)
Eclipse: start: 5010.0 end: 1440.0
Charge level: 0.628 (1980.0 seconds)
Eclipse: start: 4410.0 end: 840.0
Charge level: 0.625 (2580.0 seconds)
Eclipse: start: 3810.0 end: 240.0
2026-09-02 14:53:23,748 sats.satellite.EO1 INFO <3180.00> EO1: timed termination at 3180.0 for action_charge
2026-09-02 14:53:23,748 data.base INFO <3180.00> Total reward: {}
2026-09-02 14:53:23,749 comm.communication INFO <3180.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,749 sats.satellite.EO1 INFO <3180.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,754 gym INFO <3180.00> Step reward: 0.0
2026-09-02 14:53:23,755 gym INFO <3180.00> === STARTING STEP ===
2026-09-02 14:53:23,755 sats.satellite.EO1 INFO <3180.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,756 sats.satellite.EO1 INFO <3180.00> EO1: setting timed terminal event at 3780.0
2026-09-02 14:53:23,785 sats.satellite.EO1 INFO <3780.00> EO1: timed termination at 3780.0 for action_charge
2026-09-02 14:53:23,786 data.base INFO <3780.00> Total reward: {}
2026-09-02 14:53:23,786 comm.communication INFO <3780.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,787 sats.satellite.EO1 INFO <3780.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,788 gym INFO <3780.00> Step reward: 0.0
2026-09-02 14:53:23,789 gym INFO <3780.00> === STARTING STEP ===
2026-09-02 14:53:23,789 sats.satellite.EO1 INFO <3780.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,790 sats.satellite.EO1 INFO <3780.00> EO1: setting timed terminal event at 4380.0
Charge level: 0.993 (3180.0 seconds)
Eclipse: start: 3210.0 end: 5310.0
Charge level: 1.000 (3780.0 seconds)
Eclipse: start: 2610.0 end: 4710.0
2026-09-02 14:53:23,819 sats.satellite.EO1 INFO <4380.00> EO1: timed termination at 4380.0 for action_charge
2026-09-02 14:53:23,820 data.base INFO <4380.00> Total reward: {}
2026-09-02 14:53:23,821 comm.communication INFO <4380.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,821 sats.satellite.EO1 INFO <4380.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,822 gym INFO <4380.00> Step reward: 0.0
2026-09-02 14:53:23,823 gym INFO <4380.00> === STARTING STEP ===
2026-09-02 14:53:23,823 sats.satellite.EO1 INFO <4380.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,824 sats.satellite.EO1 INFO <4380.00> EO1: setting timed terminal event at 4980.0
2026-09-02 14:53:23,853 sats.satellite.EO1 INFO <4980.00> EO1: timed termination at 4980.0 for action_charge
2026-09-02 14:53:23,854 data.base INFO <4980.00> Total reward: {}
2026-09-02 14:53:23,854 comm.communication INFO <4980.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,854 sats.satellite.EO1 INFO <4980.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,856 gym INFO <4980.00> Step reward: 0.0
2026-09-02 14:53:23,857 gym INFO <4980.00> === STARTING STEP ===
2026-09-02 14:53:23,857 sats.satellite.EO1 INFO <4980.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,857 sats.satellite.EO1 INFO <4980.00> EO1: setting timed terminal event at 5580.0
2026-09-02 14:53:23,887 sats.satellite.EO1 INFO <5580.00> EO1: timed termination at 5580.0 for action_charge
2026-09-02 14:53:23,888 data.base INFO <5580.00> Total reward: {}
2026-09-02 14:53:23,888 comm.communication INFO <5580.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,889 sats.satellite.EO1 INFO <5580.00> EO1: Satellite EO1 requires retasking
2026-09-02 14:53:23,890 gym INFO <5580.00> Step reward: 0.0
2026-09-02 14:53:23,890 gym INFO <5580.00> === STARTING STEP ===
2026-09-02 14:53:23,891 sats.satellite.EO1 INFO <5580.00> EO1: action_charge tasked for 600.0 seconds
2026-09-02 14:53:23,891 sats.satellite.EO1 INFO <5580.00> EO1: setting timed terminal event at 6180.0
2026-09-02 14:53:23,899 data.base INFO <5700.00> Total reward: {}
2026-09-02 14:53:23,899 comm.communication INFO <5700.00> Optimizing data communication between all pairs of satellites
2026-09-02 14:53:23,901 gym INFO <5700.00> Step reward: 0.0
2026-09-02 14:53:23,901 gym INFO <5700.00> Episode terminated: False
2026-09-02 14:53:23,902 gym INFO <5700.00> Episode truncated: True
Charge level: 1.000 (4380.0 seconds)
Eclipse: start: 2010.0 end: 4110.0
Charge level: 1.000 (4980.0 seconds)
Eclipse: start: 1410.0 end: 3510.0
Charge level: 1.000 (5580.0 seconds)
Eclipse: start: 810.0 end: 2910.0
Charge level: 1.000 (5700.0 seconds)
Eclipse: start: 690.0 end: 2790.0
It is observed that the battery decrease while the satellite is in eclipse, but once the satellite is out of eclipse, the battery quickly increases to full charge.