Environment Configuration — Parallelism

One of Space Robotics Bench's most powerful features is parallel simulation, allowing you to run multiple simulation instances simultaneously. This capability is critical for:

  • Reinforcement Learning: Collect experience at scale for faster training
  • Parameter Tuning: Test multiple configurations simultaneously
  • Monte Carlo Sampling: Evaluate robustness across varied scenarios
  • Batch Processing: Process multiple scenarios in a single run

Number of Environments

The env.scene.num_envs parameter controls how many parallel simulation instances are created. This parameter is aliased as env.num_envs for brevity:

srb agent rand -e _manipulation env.scene.num_envs=16
srb agent zero -e _manipulation env.num_envs=128

Each environment is a fully independent physics simulation instance, with all cross-environment interactions disabled (filtered collisions). However, there is only one instance of the rendering engine, which means that a visual sensor in one environment will see entities from all environments. A simple workaround for this limitation is to increase the spacing between environments and clip the maximum sensor range.

Environment Spacing

The env.scene.env_spacing parameter controls the spatial distance between environments. This parameter is aliased as env.spacing for brevity:

srb agent rand -e _manipulation env.num_envs=64 env.scene.spacing=20.0
srb agent rand -e _manipulation env.num_envs=32 env.spacing=10.0

Environment Stacking

The env.stack parameter controls whether environments share assets or have independent assets:

Independent Environments (env.stack=false) [Default]

  • ⚠️ Each environment has a unique scene and position
  • ✅ Greater visual and physical diversity
  • ✅ Supports tasks with visual sensors
  • ❗ Slower to initialize
  • ❗ Higher memory usage
srb agent rand -e _manipulation env.scene.num_envs=16 env.stack=false

Stacked Environments (env.stack=true)

  • ⚠️ All environments share the same scenery and position
  • ✅ Faster to initialize
  • ✅ Lower memory usage
  • ❗ Less environmental diversity
  • ❗ Does not support tasks with visual sensors
srb agent rand -e _manipulation env.scene.num_envs=16 env.stack=true

Note: Non-visual locomotion_velocity_tracking task defaults to env.stack=true.