Agent Skill · NVIDIA NIM

tao-train-pointpillars

PointPillars for 3D object detection from LiDAR point clouds. Encodes point clouds into a pseudo-image via a pillar-based representation, then applies 2D detection — used in autonomous driving and robotics. Use when training, evaluating, exporting, pruning, retraining, or running inference for a TAO PointPillars model. Trigger phrases include "train PointPillars", "LiDAR 3D detection", "point-cloud object detection", "pillar-based 3D detector".

Provider: NVIDIA NIM Path in repo: skills/tao-train-pointpillars/SKILL.md

Skill body

PointPillars

PointPillars for 3D object detection from LiDAR point clouds. Encodes point clouds into a pseudo-image via pillar-based representation, then applies 2D detection. Used in autonomous driving / robotics.

Typically trained from scratch. Provide train.resume_training_checkpoint_path to resume.

For TAO Deploy TensorRT actions (gen_trt_engine, TensorRT evaluate, and TensorRT inference), read references/tao-deploy-pointpillars.md first. Deploy spec templates live in this skill’s references/ folder with the spec_template_deploy_*.yaml prefix.

The packaged PyTorch PointPillars CLI supports dataset_convert, train, evaluate, inference, export, and prune. It does not expose a parent-model gen_trt_engine action; TensorRT engine generation is deploy-only. It also does not expose a separate retrain subcommand. Retraining from a pruned model uses pointpillars train -e ... with train.pruned_model_path populated.

Dataclass Schemas

Generated TAO Core schemas are packaged in schemas/<action>.schema.json, with schemas/manifest.json listing available actions. Each generated schema also emits references/spec_template_<action>.yaml from the schema top-level default field. AutoML enablement is declared at the model layer in references/skill_info.yaml via automl_enabled. Runnable AutoML still requires schemas/train.schema.json and references/spec_template_train.yaml to exist and parse. Use the packaged train schema for automl_default_parameters, automl_disabled_parameters, defaults, min/max bounds, enums, option weights, math conditions, dependencies, and popular parameters. Do not expect ~/tao-core at runtime; maintainers regenerate schemas/templates before packaging the skill bank.

Train Action Policy

This model is AutoML-enabled at the model layer. Before handling any train-stage request, read references/skill_info.yaml and resolve the run override from either an explicit automl_policy value or the user’s workflow request. Use automl_policy: on by default and only expose on / off in new launch prompts. Treat phrases like “turn off AutoML”, “disable AutoML”, “no HPO”, or “plain training” as automl_policy: off for this run only. When automl_policy: on, automl_enabled: true, and both schemas/train.schema.json and references/spec_template_train.yaml are packaged, route the train action through tao-skill-bank:tao-run-automl by default with this model’s skill_dir. Preserve workflow/application overrides for datasets, specs, output directories, GPU/platform settings, parent checkpoints, and automl_policy. Use direct model training only when automl_policy: off or the packaged train schema/template is missing; in the missing-schema case, report that AutoML is enabled but not runnable for this model until schemas are generated.

Non-train actions such as evaluate, inference, export, and deploy flows stay in this model skill. The per-run automl_policy override does not change model metadata.

Training Requirements

Per-Action Dataset Requirements

Action Spec Key Source Files List?
dataset_convert dataset.data_path id   No
evaluate dataset.data_path train_datasets   No
evaluate dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No
export dataset.data_path train_datasets   No
export dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No
inference dataset.data_path train_datasets   No
inference dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No
prune dataset.data_path train_datasets   No
prune dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No
retrain dataset.data_path train_datasets   No
retrain dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No
train dataset.data_path train_datasets   No
train dataset.data_info_path train_datasets /results/{dataset_convert_job_id}/results_dir/data_info/ No

Typical Spec Overrides

Data source overrides are mandatory for every action — the agent MUST construct data source paths from the Per-Action Dataset Requirements table above and include them in spec_overrides.

DATA_ROOT = "s3://bucket/data/pointpillars"
DATA_INFO = "/results/{dataset_convert_job_id}/results_dir/data_info"
CHECKPOINT = "/results/{train_job_id}/results_dir/checkpoint_epoch_1.pth"
PRUNED_MODEL = "/results/{prune_job_id}/results_dir/pruned_0.1.tlt"

The raw PointPillars data root must be an extracted folder containing matching train/lidar, train/label, val/lidar, and val/label subfolders before dataset_convert runs. If the source dataset is packaged as separate train/val archives, extract both under the same mounted data root and point dataset.data_path at that root.

train (mandatory data sources):

{
    "train.num_epochs": 30,
    "train.checkpoint_interval": 10,
    "train.validation_interval": 10,
    "train.num_gpus": 1,
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
}

resume train (mandatory checkpoint):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "train.resume_training_checkpoint_path": CHECKPOINT,
}

evaluate (mandatory data sources):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "evaluate.checkpoint": CHECKPOINT,
}

export (mandatory data sources):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "export.checkpoint": CHECKPOINT,
    "export.onnx_file": "/results/{export_job_id}/results_dir/pointpillars.onnx",
}

inference (mandatory data sources):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "inference.checkpoint": CHECKPOINT,
}

prune (mandatory data sources):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "prune.model": CHECKPOINT,
}

retrain (mandatory data sources):

{
    "dataset.data_path": DATA_ROOT,
    "dataset.data_info_path": DATA_INFO,
    "train.pruned_model_path": PRUNED_MODEL,
}

For local Docker, DATA_INFO must be visible inside every train/evaluate/export/prune/retrain container. Use the dataset_convert job from the same results root, or mount/copy the converted results_dir/data_info folder into the current run and set dataset.data_info_path to that mounted container path. If the host scratch root is mounted at /results and the conversion artifacts live under host scratch/results/<job_id>/results_dir/data_info, the direct-job container path is /results/results/<job_id>/results_dir/data_info. Do not reuse a /results/<job_id>/... path from another run root unless that folder is mounted into the current job.

For AutoML train workflows, perform this as a launch preflight before calling AutoMLRunner.run: create or materialize the dataset_convert output under the current run’s RESULTS_ROOT, set dataset.data_info_path to that current-run container path, and verify dbinfos_train.pkl, infos_train.pkl, and infos_val.pkl are present from the train container’s point of view. If a runner is cloned or adapted from a prior AutoML algorithm, update the conversion artifact in the new run root; a stale CONVERT_JOB_ID from another results mount is not valid.

Eval Dataset

Optional. Validation data (val.tar.gz) is separate from training. Used for mAP evaluation.

Important Parameters

Multi-GPU / Multi-Node

Launch method: torchrun (LIGHTNING_EXCLUDED_NETWORK). Uses PyTorch native DistributedDataParallel (NOT Lightning Trainer).

Spec Key Description Default
train.num_gpus Number of GPUs per node 1
train.gpu_ids GPU device indices [0]
train.num_nodes Number of nodes 1

Multi-node env vars (set by orchestrator):

Variable Purpose
WORLD_SIZE Number of nodes
NODE_RANK This node’s rank
MASTER_ADDR Rank-0 node IP
MASTER_PORT Rank-0 port (default 29500)
NUM_GPU_PER_NODE GPUs per node

Hardware

Minimum 1 GPU(s), recommended 4 GPU(s). 16GB+ (V100 or A100) VRAM per GPU. PointPillars is relatively efficient for 3D detection. The main bottleneck is data I/O for large point cloud datasets.

Error Patterns

dataset_convert required: Training will fail if dataset.data_info_path is not populated from a prior dataset_convert job. Always run convert first, and verify the train container can see dbinfos_train.pkl and infos_train.pkl under dataset.data_info_path. A common local-Docker failure is a stale /results/<old_job_id>/... path from a different results root.

Point cloud range mismatch: If point_cloud_range does not match the actual sensor data extent, detections will be poor or empty.

Epoch numbering: PointPillars checkpoint epoch numbers may be offset by 1 from status.json reported epochs.

Checkpoint selection: PointPillars training emits checkpoints named like checkpoint_epoch_1.pth. For evaluation, inference, export, prune, and resume, select the intended checkpoint through the model/job checkpoint resolver and pass that exact file to evaluate.checkpoint, inference.checkpoint, export.checkpoint, prune.model, or train.resume_training_checkpoint_path. Do not guess by taking the newest model.pth; this model does not use that filename.

Prune/retrain key: PointPillars prune writes an encrypted .tlt artifact. Keep a non-empty key in the prune and retrain specs; the packaged templates use the TAO default tlt_encode. If key is omitted or null, the toolkit can still exit with a container success code while logging a passphrase error and creating an empty pruned_0.1.tlt. Always verify the pruned model is nonzero before using it for retrain.

Status files matter: Some PointPillars failures can be followed by Execution status: PASS in the entrypoint footer and a Docker exit code of 0. Check results_dir/status.json and the expected artifact before marking an action as passed.

Local results_dir wiring: For direct local-Docker specs, set the top-level results_dir as well as any action-specific *.results_dir field. If only evaluate.results_dir is set and the top-level field is left blank, evaluate can try to write under /opt/nvidia/eval and then still print the generic PASS footer. Treat that as a failed action unless the expected result directory and status/artifact files exist.

Spec Param / Parent Model Inference

Model-specific inference mappings belong in this MD file, not in config.json. Generated runners should read this section and apply the mappings with SDK helpers before create_job(). This mirrors the old microservices infer_params.py flow.

Inference mappings from TAO Core pointpillars.config.json:

Action Spec Field Inference Function Meaning
dataset_convert results_dir output_dir current job results directory
evaluate evaluate.checkpoint parent_model model file inferred from the parent job results folder
evaluate key key encryption key
evaluate results_dir output_dir current job results directory
export export.checkpoint parent_model model file inferred from the parent job results folder
export export.onnx_file create_onnx_file output ONNX path
export export.save_engine create_engine_file output TensorRT engine path
export key key encryption key
export results_dir output_dir current job results directory
inference inference.checkpoint parent_model model file inferred from the parent job results folder
inference inference.trt_engine parent_model model file inferred from the parent job results folder
inference key key encryption key
inference results_dir output_dir current job results directory
prune key key encryption key
prune prune.model parent_model model file inferred from the parent job results folder
prune results_dir output_dir current job results directory
retrain key key encryption key
retrain results_dir output_dir current job results directory
retrain train.pruned_model_path parent_model model file inferred from the parent job results folder
train key key encryption key
train model.pretrained_model_path ptm_if_no_resume_model PTM when no resume checkpoint exists
train results_dir output_dir current job results directory
train train.resume_training_checkpoint_path resume_model model file inferred from the current job results folder

For parent_model or parent_model_folder, pass the upstream train/export/AutoML child job id as parent_job_id. The SDK lists the parent result folder, filters checkpoint artifacts, and returns the selected model file or folder. Do not add these mappings back to config.json and do not patch generated runner scripts to guess checkpoint paths.

Deployment

Skill frontmatter

license: Apache-2.0 compatibility: Requires docker + nvidia-container-toolkit. metadata: {"version" => "0.1.0", "author" => "NVIDIA Corporation"} allowed-tools: Read Bash tags: pointcloud3ddetection