graspgenx

name

graspgenx

description

Run and operate GraspGenX — a cross-embodiment foundation model for 6-DOF grasp generation. Use when installing GraspGenX (uv or Docker), running inference demos (segmented object point cloud, scene point cloud, or object mesh), choosing a gripper or planner (graspmoe vs diffusion), starting or calling the ZMQ client-server, driving grasping through the MCP server, integrating a new gripper (config wizard / sweep-volume params), or wiring grasps into an end-to-end cuRobo + Newton pick-and-place pipeline. Also covers checkpoint/asset setup and the depth-quality requirement for real-world use.

GraspGenX

GraspGenX is a cross-embodiment grasp model: one model, conditioned on a gripper's swept volume, predicts 6-DOF grasps for any gripper — including grippers unseen in training. (GraspGen, the predecessor, trained one model per gripper; GraspGenX does not.) Output is a set of (K, 4, 4) SE(3) grasp poses plus (K,) confidence scores; higher score = better, and visualizers color grasps red→green by score.

Repo layout (what lives where):

Path	Purpose
graspgenx/	The package: model, samplers, serving/ (ZMQ), x_grippers.py, utils
scripts/	Demos, list_grippers.py, gripper_config_wizard.py, client-server examples
client-server/	ZMQ inference server + CLI client
mcp/	MCP server bridging LLM tool-calls → the ZMQ server
end2end/	GraspGenX → cuRobo → Newton/MuJoCo pick-and-place pipeline
assets/	sample_data/, proc_grippers/
ext/	Auto-cloned checkpoints + gripper descriptions (see below)

Convention: run every command with uv run python … from the repo root.

Checkpoints & gripper assets (automatic)

On the first import graspgenx, two Hugging Face repos are shallow-cloned (needs git + git-lfs on PATH) into ext/:

• Model checkpoints → ext/graspgenx_checkpoints/release/{gen,dis}/ (each has config.yaml + epoch_*.pth).
• Gripper descriptions → ext/gripper_descriptions/.

Override the locations if you already have them elsewhere:

export GRASPGENX_CHECKPOINT_DIR=/path/to/graspgenx_checkpoints
export GRASPGENX_GRIPPER_CFG_DIR=/path/to/gripper_descriptions   # must already exist

Verify the assets resolve:

uv run python -c "from graspgenx import get_gripper_descriptions_root; print(get_gripper_descriptions_root())"
uv run python scripts/list_grippers.py        # all available grippers

---

1. Installation

Pick uv for inference, Docker for training (Docker also does inference).

uv (recommended for inference)

git clone https://github.com/NVlabs/GraspGenX.git && cd GraspGenX && uv sync

Python ≥ 3.10; torch is pinned >=2.1,<2.7 and uv auto-selects the matching CUDA wheel (torch-backend = "auto"). pip install -e . also works inside a conda / venv on Python 3.10 or 3.11.

Optional extras (add only what you need):

Command	Adds
uv sync --extra serve	ZMQ client-server (pyzmq, msgpack, msgpack-numpy)
uv sync --extra tensorrt	TensorRT acceleration for the diffusion denoiser
uv sync --extra end2end	cuRobo + Newton/MuJoCo + CoACD + USD + fcl (pick-and-place)
uv sync --extra dev	black, isort, flake8

Docker (training + inference)

bash docker/build.sh          # builds image  x_grasp:3.0  and  x_grasp:latest

Base image nvcr.io/nvidia/pytorch:25.03-py3, WORKDIR /code/. The image has no CMD/ENTRYPOINT and there is no docker-compose file — mount the repo and run commands yourself:

docker run --gpus all -v "$PWD":/code -it x_grasp:latest bash
# inside: python scripts/demo_object_pc.py ...   (uv is not required in Docker)

For headless rendering (no display) in Docker or over SSH, prefix commands with PYOPENGL_PLATFORM=egl.

---

2. Inference — the mental model

Every inference picks three things:

1. Input modality — segmented object point cloud, full scene point cloud, or object mesh.
2. --gripper_name — one of 26 built-in grippers (see list_grippers.py): robotiq_2f_85, robotiq_2f_140, robotiq_3f, robotiq_hande, franka_panda, franka_umi, inspire_hand, surge_hand, barrett_hand, unitree_g1, galaxea_g1, ezgripper, arx_x5, abb_yumi, bd_spot, dh_ag95, fetch_robot, onrobot_RG2, onrobot_RG6, piper_hand, sawyer_hand, schunk_wsg50, sharpa_wave, tesollo_delto2f, wuji_hand, xarm_hand. (Plus any gripper you add — see §6.)
3. --planner — graspmoe (default; diffusion ∪ oriented-bounding-box grasps, all scored by the discriminator) or diffusion (diffusion sampler only, faster).

Visualization: demos serve an interactive viser GUI at http://localhost:8080 (open it in a browser; click Next to cycle objects, top grasp shown in blue). The port is fixed at 8080 — there is no --port flag on the demo scripts; if 8080 is taken, the actual port is printed in the log. Over SSH, forward it: ssh -N -L 8080:localhost:8080 <host>.

Sample inputs under assets/sample_data/: real_world/{00,01}/ (depth + seg + meta scenes), object_pc/*.json, object_mesh/{banana,box}.obj, hope_objects/*.obj.

---

3. Inference demos

demo_object_pc.py — segmented object point clouds

Runs inference on one pre-segmented object at a time.

uv run python scripts/demo_object_pc.py \
    --sample_data_dir assets/sample_data/real_world \
    --gripper_name robotiq_2f_85 \
    --plot_top_mesh

--gripper_name accepts multiple grippers (compare side by side). Common flags: --planner {graspmoe,diffusion}, --grasp_threshold 0.7 (-1.0 = keep top-k instead), --num_grasps 200, --return_topk --topk_num_grasps 100, --plot_top_mesh (gripper mesh at the top grasp), --moe_obb_density {sparse,dense,dense-topandside} (default dense-topandside).

demo_scene_pc.py — objects within a full scene

Loads a full-scene point cloud with per-object segmentation, runs inference on every object, and filters grasps that collide with the rest of the scene.

uv run python scripts/demo_scene_pc.py \
    --sample_data_dir assets/sample_data/real_world \
    --gripper_name robotiq_2f_85 \
    --scene 00

Collision filtering is on by default; disable with --no-filter_collisions. --scene 00 restricts to a single real_world scene. --plot_top_mesh is on by default here (--no-plot_top_mesh to disable). Related: demo_scene_pc_fused.py runs generation + scoring through one fused TensorRT engine (diffusion-only, requires CUDA).

demo_object_mesh.py — object meshes

Samples surface points from a mesh, runs inference, visualizes mesh + grasps.

uv run python scripts/demo_object_mesh.py \
    --mesh_file assets/sample_data/object_mesh/banana.obj \
    --mesh_scale 1.0 \
    --gripper_name inspire_hand \
    --grasp_threshold -1.0 --return_topk --topk_num_grasps 100 --plot_top_mesh

Formats: .obj, .stl, .ply, USD (.usd/.usda/.usdc/.usdz). For headless/batch (no viewer) that writes grasps to a YAML in the Isaac grasp format:

uv run python scripts/demo_object_mesh.py --mesh_file <mesh> --gripper_name <g> \
    --no-visualization --output_file /tmp/grasps.yml

Other inference entrypoints

• scripts/batch_inference_scene.py — headless, one batched pass over a scene, optional .npz output (--output_file).
• scripts/inference_xgrasp.py — Hydra-driven large-scale eval to H5 (config overrides, not argparse).

---

4. MCP server (LLM-driven grasping)

mcp/ is a lightweight bridge so an LLM (Claude Desktop, Cursor, VS Code) can call GraspGenX as tools. It needs no CUDA and no model weights — it forwards requests over ZMQ to a running GraspGenX server:

LLM  ──MCP (stdio)──▶  mcp/ bridge  ──ZMQ (tcp)──▶  GraspGenX server (GPU)

Prerequisite: the ZMQ server (§5) must already be running.

Install and register:

cd mcp && uv venv --python 3.10 .venv && source .venv/bin/activate && uv pip install -e .

Tools exposed: generate_grasps_from_mesh, generate_grasps_from_point_cloud, generate_grasps_from_sweep_volume (params-only, no server assets), visualize_grasps, graspgenx_health_check, graspgenx_server_info. Being cross-embodiment, the grasp tools take a gripper_name per call.

Client config (Cursor .cursor/mcp.json shown; Claude Desktop / VS Code are the same shape — see mcp/README.md for all three):

{
  "mcpServers": {
    "graspgenx": {
      "command": "uv",
      "args": ["run", "--directory", "/absolute/path/to/GraspGenX/mcp", "mcp-server-graspgenx"],
      "env": { "GRASPGENX_HOST": "localhost", "GRASPGENX_PORT": "5556" }
    }
  }
}

---

5. ZMQ client-server

Serve GraspGenX once (model loaded on GPU) and let any process — same machine or across the network, no GPU/torch needed client-side — request grasps.

Start the server

uv sync --extra serve        # one-time: ZMQ deps
uv run python client-server/graspgenx_server.py \
    --config ext/graspgenx_checkpoints/release \
    --assets_dir assets \
    --port 5556 \
    --default_gripper franka_panda        # optional; used when a client omits gripper_name

--config is the checkpoint root directory (the one containing gen/ and dis/), not the inner config.yaml. Optional TensorRT: --tensorrt --tensorrt_precision {fp32,fp16} --tensorrt_rollout {per_step,unrolled}. The model loads eagerly at startup; per-gripper samplers load lazily and are cached.

Wire actions (four modes)

Action	Input	Gripper spec	Threshold/top-k
infer	object point cloud	gripper_name (name-based)	server-side
infer_object	segmented object PC	sweep-volume params (12 numbers)	client-side
infer_scene_depth	depth (m) + intrinsics + instance mask	sweep-volume params	client-side
infer_scene_pc	scene PC + instance mask	sweep-volume params	client-side

The three sweep-volume modes return all generated grasps with scores and reject gripper_name/grasp_threshold/topk on the wire — the client applies thresholding/top-k. health → {"status":"ok"}; metadata → default/loaded grippers + model config.

CLI client and worked examples

# General CLI client (mesh or point cloud → grasps, optional viser):
uv run python client-server/graspgenx_client.py \
    --mesh_file assets/sample_data/object_mesh/box.obj --gripper_name franka_panda \
    --host localhost --port 5556 --visualize

# Three mode examples (run the server first, then in a second terminal):
uv run python scripts/client_server_example_1.py --gripper_name robotiq_2f_85 --port 5556  # scene depth
uv run python scripts/client_server_example_2.py --gripper_name robotiq_2f_85 --port 5556  # scene PC
uv run python scripts/client_server_example_3.py --gripper_name robotiq_2f_85 --port 5556  # single object

Python API

from graspgenx.serving import GraspGenXClient, SweepVolumeParams

with GraspGenXClient(host="localhost", port=5556) as client:
    print(client.server_metadata)
    grasps, conf = client.infer(point_cloud, gripper_name="franka_panda")          # (K,4,4), (K,)
    # params-only (no server assets for the gripper):
    params = SweepVolumeParams.from_gripper_config("franka_panda")                  # or build 12 numbers directly
    grasps, conf = client.infer_object(object_pc, params, planner="graspmoe")
    per_instance = client.infer_scene_pc(scene_pc, instance_mask, params)          # {id: (grasps, conf)}

infer_scene_depth / infer_scene_pc return a {instance_id: (grasps, conf)} dict; pass return_branch_tags=True to also get per-grasp "diff"/"obb" tags.

---

6. Integrating a new gripper

GraspGenX runs zero-shot on any gripper given a URDF + meshes. The only thing it needs beyond a stock URDF is a config.json describing the open/close joint states and the swept-volume boxes that condition the model. An interactive wizard generates it.

Run the wizard

uv run python scripts/gripper_config_wizard.py \
    --urdf /path/to/your/gripper.urdf \
    --name <gripper_name> \
    --port 8081

Open http://localhost:8081 and step through six panels (click Confirm to advance): 1 align base frame (+Z = approach along the fingers, +X = closing direction) → 2 confirm fully-open joint pose → 3 drag the blue box to enclose the inner finger volume at open → 4 set the closed pose, drag the orange box for the half-open volume → 5 review the open↔close animation → 6 pick gripper type + symmetry and save.

What gets written

Into <gripper_descriptions_root>/…/assets/x_grippers/<name>/ (root resolved via GRASPGENX_GRIPPER_CFG_DIR, else ext/gripper_descriptions/):

• gripper.urdf + meshes/ — copied from your source.
• vis_mesh.obj — merged visual mesh at the open pose.
• config.json — the model conditioning. Key fields:

{
  "open":  { "<joint>": <float>, ... },     // fully-open joint state
  "close": { "<joint>": <float>, ... },     // closed joint state
  "fingertip": [x, y, z],                    // fingertip point (z = depth)
  "sweep_volume": {
    "extents":  [ex, ey, ez], "offset":  [ox, oy, oz],   // open box
    "extents2": [ex, ey, ez], "offset2": [ox, oy, oz    
  
      
   x4    ...  ...

Collision mesh, point-cloud, and TSDF caches are generated lazily on first use — nothing else to run.

Verify, then use it

uv run python scripts/vis_gripper_desc.py --gripper <gripper_name> --port 8081   # animates open↔close + boxes
uv run python scripts/demo_object_pc.py \
    --sample_data_dir assets/sample_data/real_world \
    --gripper_name <gripper_name> --plot_top_mesh

Params-only alternative: you can skip on-disk assets entirely and feed the gripper as 12 raw sweep-volume numbers at inference time via SweepVolumeParams (the infer_object/scene actions in §5, or the MCP generate_grasps_from_sweep_volume tool).

If you onboard a gripper not already in the shared set, please upstream the saved assets/x_grippers/<name>/ directory via a PR.

---

7. End-to-end: grasps → cuRobo motion planning → sim

end2end/ wires GraspGenX into a closed-loop pick-and-place pipeline:

GraspGenX grasps per object → cuRobo plans a collision-free approach→grasp→lift trajectory to a reachable, collision-free grasp → Newton/MuJoCo replays it under gravity + contacts → renders MP4 + exports USD for Isaac Sim / Omniverse.

Install

uv sync                                 # base
uv sync --extra end2end                 # + cuRobo, Newton/MuJoCo, CoACD, USD, fcl
python end2end/setup_end2end_deps.py    # clones cuRobo source into ext/curobo, builds merged URDFs

Note: an older pyproject comment mentions sibling ../curobo / ../newton checkouts and a [tool.uv.sources] index — those are stale. The real path is the --extra end2end install plus setup_end2end_deps.py (idempotent).

Run a demo (from repo root, headless)

PYOPENGL_PLATFORM=egl PYGLET_HEADLESS=true uv run python end2end/e2e_grasp_demo.py \
  --robot_config end2end/robots/franka_panda.yaml \
  --env_config   end2end/envs/single_bin_demo.yaml \
  --task clutter_pick_and_drop --playback_mode dynamic --no-viser \
  --num_grasps 200 --topk 80 --grasp_threshold 0.7 --planner graspmoe \
  --seed 0 --export-trajectory end2end/runs/franka_single/trajectory.json

Three demos ship: Franka single-object → bin (above), Franka 3-object clutter → bin (envs/franka_clutter3_demo.yaml, add --max_retries_per_object 2), and UR10e + arx_x5 pick-and-lift (robots/ur10e_arx_x5.yaml + envs/tabletop_single_nobin.yaml, add --mesh_file … --hold_after_close_frames 150). Each writes a trajectory.json; render it decoupled from the sim:

PYOPENGL_PLATFORM=egl uv run python end2end/render_trajectory_mp4.py \
  --trajectory end2end/runs/franka_single/trajectory.json \
  --output end2end/runs/franka_single/demo.mp4 --resolution 320x240 --no-texture
PYOPENGL_PLATFORM=egl uv run python end2end/export_trajectory_usd.py \
  --trajectory end2end/runs/franka_single/trajectory.json \
  --output end2end/runs/franka_single/demo.usda

How the grasps drive cuRobo

The bridge between a GraspGenX grasp and a cuRobo plan is small and reusable:

1. Frame convert. A predicted grasp is a world-frame (4,4) pose in the canonical grasp frame. Each robot YAML supplies a grasp_to_tool_transform (grasp frame → the arm's tool0/TCP frame); apply it so cuRobo targets the tool link, not the grasp point. (See robot_profiles.py, end2end/visualize_scene_grasps.py.)
2. Collision-filter first. Score each grasp's gripper mesh against the table/bin/neighbors/target with fcl and hand cuRobo only the collision-free grasps — cuRobo never plans to a geometrically colliding grasp.
3. Plan. Build the goal with curobo_compat.grasp_goals(...) (returns a curobo.types.Pose or, on the lab fork, a GoalToolPose) and call MotionPlanner.plan_grasp(...). Pass all top-K feasible grasps at once and cuRobo picks the most reachable; it returns approach→grasp→lift (falling back to approach+grasp when no feasible retraction exists). curobo_compat.py papers over the two plan_grasp signatures.

Minimal shape of the handoff (see e2e_grasp_demo.py / clutter_task.py):

from curobo.motion_planner import MotionPlanner, MotionPlannerCfg
from curobo_compat import grasp_goals

# grasps_world: (K,4,4) from GraspGenX, already filtered to collision-free
tool_poses = [world_grasp @ grasp_to_tool_transform for world_grasp in grasps_world]
goal = grasp_goals(tool_poses, target_link=tool_frame)   # Pose / GoalToolPose
result = planner.plan_grasp(goal, start_state)           # approach → grasp → lift

⚠️ Real-world requirements & limitations

The demos use complete mesh-sampled or clean simulated point clouds. Deploying on a real robot adds several requirements, and each is a source of error that bounds grasp performance:

• Calibrated camera. You need a camera with known intrinsics (focal length, principal point — for back-projecting depth to a metric point cloud) and extrinsics (the camera→robot-base transform — so planned grasps land in the robot's frame). infer_scene_depth takes intrinsics directly; extrinsics are what put the grasp where cuRobo can reach it.

• Good depth. Grasp quality is bounded by depth quality; noisy or incomplete depth (reflective/transparent/thin objects, stereo holes) degrades grasps. Feed it good depth via FoundationStereo (learned stereo → dense accurate depth from a stereo pair) or a LIDAR / time-of-flight depth camera for direct high-quality range data.

• Instance segmentation of the target. The model consumes a segmented object point cloud (or a per-object instance mask). Segment the target with an instance segmenter such as SAM2 or SAM3, then use the mask to carve the object's points out of the scene cloud — that segmented cloud is the input to infer / infer_object (or feed the mask to infer_scene_depth / infer_scene_pc).

• Downstream execution error. Even with perfect grasps, camera-calibration error (intrinsics/extrinsics) and robot control / execution error (joint tracking, TCP calibration, gripper timing) shift where the gripper actually arrives versus where the grasp was predicted — both degrade real-world success independent of the model. Budget for them when a sim-perfect grasp misses on hardware.

---

Debugging & gotchas

• Two-process order for MCP/serving: start the ZMQ server first, then the MCP bridge or example client. Use graspgenx_health_check (MCP) or --host/--port to confirm reachability.
• Viewer: demos are fixed to viser :8080 (no --port flag); forward the port over SSH.
• Planner choice: graspmoe (default) is highest quality; diffusion is faster.
• grasp_threshold: 0.7 keeps confident grasps; -1.0 disables the threshold and returns top-k instead.
• Tests: uv run --no-sync pytest -m "not end2end" (fast); uv run pytest tests/test_end2end_demos.py -m end2end -v -s (slow, GPU).