MLOps for Physical AI¶
Why MLOps matters more for robots¶
If you have experience with ML in production — model training pipelines, experiment tracking, model registries, A/B testing — you have a head start. But MLOps for physical AI introduces constraints that software ML does not face:
Physical consequences of model failures. A recommendation model that serves a bad suggestion loses a click. A robot policy that generates a bad action damages equipment, drops a part, or injures a person. The deployment pipeline must be more rigorous.
Multi-stage artifact chain. A software ML model has a dataset and a checkpoint. A physical AI model has a simulation scene, synthetic data generation parameters, domain randomization settings, domain adaptation outputs, training hyperparameters, evaluation results in simulation, evaluation results on hardware, and deployment configuration. Every link in this chain must be traceable.
Environment-dependent performance. A language model works the same way regardless of where it runs (modulo hardware speed). A robot policy trained in simulation may behave differently on different physical robots due to calibration differences, sensor variations, and environmental factors. Deployment must account for per-site calibration.
Safety certification. Regulated industries (automotive, aerospace, pharmaceutical) require evidence that the deployed model meets safety standards. This means tracing from the deployed inference endpoint back through the training pipeline to the source data, with every step auditable and reproducible.
The physical AI MLOps lifecycle¶
1. Data Collection
├── Simulation: Isaac Sim scenes, domain randomization, synthetic data
├── Teleoperation: Human-operated robot demonstrations
└── Production: Real-world data from deployed robots
2. Data Preparation
├── Domain adaptation (Cosmos Transfer)
├── Data curation and filtering (Cosmos Reason)
└── Dataset assembly and versioning
3. Training
├── Foundation model fine-tuning (LoRA, full fine-tune)
├── Distributed training (multi-GPU, multi-node)
└── Experiment tracking (MLflow)
4. Evaluation
├── Simulation evaluation (Isaac Sim, task success rate)
├── Hardware validation (real-robot test suite)
└── Safety verification (constraint checking)
5. Registration
├── Model registry entry (version, lineage, metrics)
├── Artifact signing (Sigstore)
└── SBOM generation
6. Deployment
├── Promotion (GitOps: PR → review → merge → Argo CD sync)
├── Model serving (KServe, vLLM, custom predictor)
└── Per-site configuration (calibration, safety limits)
7. Monitoring
├── Inference telemetry (latency, throughput, error rate)
├── Task performance (success rate, completion time)
├── Anomaly detection (behavioral drift)
└── Fleet-level analytics
Key MLOps components¶
Experiment tracking (MLflow)¶
MLflow records every training run with its hyperparameters, metrics, artifacts, and lineage. For physical AI, the experiment record must include:
- Source data: Which simulation scenes were used? What domain randomization parameters? What teleoperation sessions?
- Training configuration: Model architecture, learning rate, batch size, number of steps, GPU type, training duration.
- Metrics: Training loss, validation loss, simulation task success rate, sim-to-real transfer accuracy.
- Artifacts: Model checkpoints, evaluation videos, configuration files.
MLflow provides the audit trail: given a deployed model, you can trace back to exactly how it was trained, on what data, with what results.
Training pipelines (Kubeflow Pipelines / KFP v2)¶
Kubeflow Pipelines automate the training workflow as a directed acyclic graph (DAG) of steps:
Data preparation → Fine-tuning → Evaluation → Validation → Registration
Each step runs as a container in Kubernetes. Pipelines ensure reproducibility — the same pipeline definition with the same inputs produces the same outputs. They also handle resource scheduling (GPU allocation), artifact passing between steps, and failure handling.
In the physical AI context, the pipeline often includes simulation- specific steps:
Scene generation → Synthetic data rendering → Domain adaptation →
Dataset assembly → Fine-tuning → Sim evaluation → Hardware evaluation →
Model registration
Model registry¶
A centralized catalog of trained models with metadata: version, source dataset, training run, evaluation metrics, deployment status, and lineage. The registry is the handoff point between training (data science) and deployment (platform engineering).
For physical AI, the registry must capture robot-specific metadata:
- Embodiment: Which robot platform is this model trained for?
- Action space: What actions does the model output?
- Sensor requirements: What cameras/sensors does the model expect?
- Safety constraints: What are the model's operational limits?
Model serving (KServe)¶
KServe provides Kubernetes-native model serving with:
- InferenceService: A CRD that declares what model to serve, from where, with what resources.
- ServingRuntime: Defines the inference engine (vLLM for transformer-based VLAs, custom predictors for other architectures).
- Autoscaling: Scale replicas based on request load, including scale-to-zero for bursty workloads.
- Canary deployment: Route a percentage of traffic to a new model version for gradual rollout.
For physical AI, model serving latency is critical: inference must complete within the robot's control loop deadline (typically 10–100ms for manipulation, 50–500ms for navigation).
GitOps for model deployment¶
Model promotion in physical AI follows the GitOps pattern:
- Training completes → model registered in registry with version and metrics.
- Promotion request → a PR is opened that updates the InferenceService manifest in Git to point to the new model version.
- Review → human (or automated) review checks metrics, safety evaluation results, and lineage.
- Merge → the PR is merged, changing the declared state in Git.
- Sync → Argo CD detects the change and rolls out the new model version.
- Verify → monitoring confirms the new model performs as expected in production.
This pattern provides the auditability that regulated industries require: every model deployment is a reviewed, approved Git commit with a traceable chain from training data to production serving.
Rollback¶
If the new model causes degraded performance or safety concerns:
git revertthe promotion commit.- Argo CD detects the revert and rolls back to the previous model version.
- The rollback is another Git commit — auditable, timestamped, with the reason documented.
This is identical to how configuration rollbacks work in GitOps — the model is just another piece of declarative cluster state.
Physical AI-specific challenges¶
Sim-to-real evaluation¶
Simulation evaluation (task success rate in Isaac Sim) is necessary but not sufficient. A model that achieves 95% success in simulation may achieve 60% on real hardware due to the sim-to-real gap. The evaluation pipeline must include real-hardware tests before promotion, even if they are limited in scope.
Per-site calibration¶
A warehouse in Phoenix and a warehouse in Munich have different layouts, lighting, and ambient conditions. A model fine-tuned on one may underperform on the other. The deployment pipeline must support per-site configuration (camera calibration, workspace boundaries, safety zones) without retraining the model.
Continuous learning¶
Deployed robots generate data that can improve future models. The challenge is closing this loop while maintaining data quality (not all production data is useful for training), privacy (production data may contain PII), and safety (a model trained on production data inherits any biases or errors in that data).
Fleet-wide consistency¶
When managing a fleet of robots across multiple sites, the deployment pipeline must ensure version consistency — or intentional version differences where sites are at different rollout stages. ACM (Advanced Cluster Management) and ApplicationSets provide the multi-cluster deployment mechanisms.
Key takeaways¶
- MLOps for physical AI requires rigorous traceability from deployed model back through training, evaluation, and source data — more rigorous than software ML because failures have physical consequences.
- The lifecycle includes simulation-specific stages: scene generation, synthetic data rendering, domain adaptation, and sim-to-real evaluation.
- GitOps provides the deployment mechanism: model promotions are reviewed PRs, and rollbacks are git reverts.
- Experiment tracking (MLflow), training pipelines (KFP), model registries, and model serving (KServe) compose into the full stack.
Further reading¶
- MLflow Documentation — Open-source experiment tracking and model registry.
- Kubeflow Pipelines — Kubernetes-native ML pipeline orchestration.
- KServe Documentation — Kubernetes-native model serving.
- Sculley, D., et al. (2015). "Hidden Technical Debt in Machine Learning Systems." NeurIPS 2015. — The foundational paper on the operational challenges of ML in production.