mujoco sim bridge

[jca0]

sim bridge to simulate xarm7 in mujoco
created xarm7 sim driver, general sim bridge, xarm specific sim bridge

command to test: python3 -m dimos.simulation.sim_blueprints

todos: add sim support for piper arm, mujoco viewer doesn't work on mac

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Greptile Summary

Implements MuJoCo simulation bridge for xArm7 manipulator, enabling unified driver code to work with both hardware and simulation. The implementation follows a clean architecture with a base bridge class and xArm-specific extensions that mimic the UFACTORY SDK interface.

Key changes:

• Added MujocoSimBridgeBase providing threading infrastructure, MuJoCo model loading, simulation loop at configurable frequency, and viewer integration
• Implemented XArmSimBridge that mimics UFACTORY SDK with position/velocity control modes, periodic state reporting callbacks, and best-effort SDK method implementations via __getattr__
• Created XArmSimDriver and XArmSimSDKWrapper integrating simulation with existing component-based driver architecture
• Added simulation blueprint xarm7_trajectory_sim with LCM transport configuration
• Enhanced xArm state query component with additional RPC methods for servo angles and FT sensor data
• Cleaned up deprecated agent framework code (5000+ lines removed)
• Added robot_descriptions dependency for loading robot models from Menagerie
• Included test script for subscribing to joint states

Confidence Score: 4/5

• This PR is safe to merge with one minor syntax fix needed
• The simulation bridge implementation is well-structured with proper threading, locking, and error handling. The architecture cleanly separates concerns between base and derived classes. One syntax error was found (unused expression on line 103 of xarm_sim_bridge.py) that should be fixed before merge. The deprecated code cleanup is straightforward deletion with no logical issues.
• dimos/simulation/manipulators/mujoco_sim/xarm_sim_bridge.py needs the syntax fix on line 103

Important Files Changed

Filename	Overview
dimos/simulation/manipulators/mujoco_sim/xarm_sim_bridge.py	Added XArm simulation bridge mimicking UFACTORY SDK; has one unused variable calculation on line 103
dimos/simulation/manipulators/mujoco_sim/bridge_base.py	Added base class for MuJoCo simulation bridges with threading, state management, and viewer integration
dimos/simulation/manipulators/mujoco_sim/xarm_sim_driver.py	Added MuJoCo-native xArm driver with SDK wrapper, integrates with component-based architecture
dimos/simulation/sim_blueprints.py	Added simulation blueprint for xArm7 with trajectory controller using MuJoCo backend
dimos/hardware/manipulators/xarm/components/state_queries.py	Added RPC methods for servo angles, FT sensor data, and removed unused type hints
pyproject.toml	Added robot_descriptions dependency for MuJoCo model loading

Sequence Diagram

sequenceDiagram
    participant User
    participant XArmSimDriver
    participant XArmSimSDKWrapper
    participant XArmSimBridge
    participant MujocoSimBridgeBase
    participant MuJoCo
    participant Viewer

    User->>XArmSimDriver: Initialize with config
    XArmSimDriver->>XArmSimSDKWrapper: Create SDK wrapper
    XArmSimDriver->>XArmSimDriver: Setup components

    User->>XArmSimSDKWrapper: connect(config)
    XArmSimSDKWrapper->>XArmSimBridge: Create bridge instance
    XArmSimBridge->>MujocoSimBridgeBase: __init__()
    MujocoSimBridgeBase->>MuJoCo: Load robot description
    MujocoSimBridgeBase-->>XArmSimBridge: Model & Data ready
    
    XArmSimSDKWrapper->>XArmSimBridge: connect()
    XArmSimBridge->>MujocoSimBridgeBase: connect()
    MujocoSimBridgeBase->>MujocoSimBridgeBase: Start sim_thread
    XArmSimBridge->>XArmSimBridge: Start report_thread
    
    par Simulation Loop (sim_thread)
        loop Control Frequency (100 Hz)
            MujocoSimBridgeBase->>Viewer: launch_passive()
            MujocoSimBridgeBase->>XArmSimBridge: _apply_control()
            XArmSimBridge->>MuJoCo: Update ctrl[] with targets
            MujocoSimBridgeBase->>MuJoCo: mj_step()
            MuJoCo-->>MujocoSimBridgeBase: Updated state
            MujocoSimBridgeBase->>Viewer: sync()
            MujocoSimBridgeBase->>XArmSimBridge: _update_joint_state()
            XArmSimBridge->>XArmSimBridge: Update positions/velocities/efforts
        end
    and Report Loop (report_thread)
        loop Report Frequency (100 Hz)
            XArmSimBridge->>XArmSimBridge: _notify_report()
            XArmSimBridge->>User: report_callback(state data)
        end
    end

    User->>XArmSimSDKWrapper: set_joint_positions(positions)
    XArmSimSDKWrapper->>XArmSimBridge: set_servo_angle_j()
    XArmSimBridge->>XArmSimBridge: Update _joint_position_targets
    Note over XArmSimBridge,MuJoCo: Targets applied in next control loop

    User->>XArmSimSDKWrapper: get_joint_positions()
    XArmSimSDKWrapper->>XArmSimBridge: get_servo_angle()
    XArmSimBridge-->>XArmSimSDKWrapper: Current joint angles
    XArmSimSDKWrapper-->>User: Joint positions

    User->>XArmSimSDKWrapper: disconnect()
    XArmSimSDKWrapper->>XArmSimBridge: disconnect()
    XArmSimBridge->>XArmSimBridge: Stop report_thread
    XArmSimBridge->>MujocoSimBridgeBase: disconnect()
    MujocoSimBridgeBase->>MujocoSimBridgeBase: Stop sim_thread
    MujocoSimBridgeBase->>Viewer: Close viewer

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_{54 files reviewed, 1 comment}

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[spomichter]

@jca0 thanks for attempting agents_deprecated rip out but thats out of scope here and needs to be done carefully since we are using some code in there still. revert those deletions

[jca0]

oops must've deleted on accident, it's added back now